Class: BigDecimal
- Inherits:
-
Numeric
- Object
- Numeric
- BigDecimal
- Defined in:
- ext/bigdecimal/bigdecimal.c,
lib/bigdecimal/util.rb,
ext/bigdecimal/bigdecimal.c
Overview
BigDecimal provides arbitrary-precision floating point decimal arithmetic.
Introduction
Ruby provides built-in support for arbitrary precision integer arithmetic.
For example:
42**13 #=> 1265437718438866624512
BigDecimal provides similar support for very large or very accurate floating point numbers.
Decimal arithmetic is also useful for general calculation, because it provides the correct answers people expect–whereas normal binary floating point arithmetic often introduces subtle errors because of the conversion between base 10 and base 2.
For example, try:
sum = 0
10_000.times do
sum = sum + 0.0001
end
print sum #=> 0.9999999999999062
and contrast with the output from:
require 'bigdecimal'
sum = BigDecimal("0")
10_000.times do
sum = sum + BigDecimal("0.0001")
end
print sum #=> 0.1E1
Similarly:
(BigDecimal(“1.2”) - BigDecimal(“1.0”)) == BigDecimal(“0.2”) #=> true
(1.2 - 1.0) == 0.2 #=> false
Special features of accurate decimal arithmetic
Because BigDecimal is more accurate than normal binary floating point arithmetic, it requires some special values.
Infinity
BigDecimal sometimes needs to return infinity, for example if you divide a value by zero.
BigDecimal(“1.0”) / BigDecimal(“0.0”) #=> Infinity BigDecimal(“-1.0”) / BigDecimal(“0.0”) #=> -Infinity
You can represent infinite numbers to BigDecimal using the strings 'Infinity'
, '+Infinity'
and '-Infinity'
(case-sensitive)
Not a Number
When a computation results in an undefined value, the special value NaN
(for ‘not a number’) is returned.
Example:
BigDecimal(“0.0”) / BigDecimal(“0.0”) #=> NaN
You can also create undefined values.
NaN is never considered to be the same as any other value, even NaN itself:
n = BigDecimal(‘NaN’) n == 0.0 #=> false n == n #=> false
Positive and negative zero
If a computation results in a value which is too small to be represented as a BigDecimal within the currently specified limits of precision, zero must be returned.
If the value which is too small to be represented is negative, a BigDecimal value of negative zero is returned.
BigDecimal(“1.0”) / BigDecimal(“-Infinity”) #=> -0.0
If the value is positive, a value of positive zero is returned.
BigDecimal(“1.0”) / BigDecimal(“Infinity”) #=> 0.0
(See BigDecimal.mode for how to specify limits of precision.)
Note that -0.0
and 0.0
are considered to be the same for the purposes of comparison.
Note also that in mathematics, there is no particular concept of negative or positive zero; true mathematical zero has no sign.
bigdecimal/util
When you require bigdecimal/util
, the #to_d method will be available on BigDecimal and the native Integer, Float, Rational, and String classes:
require ‘bigdecimal/util’
42.to_d # => 0.42e2
0.5.to_d # => 0.5e0
(2/3r).to_d(3) # => 0.667e0
"0.5".to_d # => 0.5e0
License
Copyright © 2002 by Shigeo Kobayashi <[email protected]>.
BigDecimal is released under the Ruby and 2-clause BSD licenses. See LICENSE.txt for details.
Maintained by mrkn <[email protected]> and ruby-core members.
Documented by zzak <[email protected]>, mathew <[email protected]>, and many other contributors.
Constant Summary collapse
- VERSION =
The version of bigdecimal library
rb_str_new2(RUBY_BIGDECIMAL_VERSION)
- BASE =
Base value used in internal calculations. On a 32 bit system, BASE is 10000, indicating that calculation is done in groups of 4 digits. (If it were larger, BASE**2 wouldn’t fit in 32 bits, so you couldn’t guarantee that two groups could always be multiplied together without overflow.)
INT2FIX((SIGNED_VALUE)VpBaseVal())
- EXCEPTION_ALL =
Determines whether overflow, underflow or zero divide result in an exception being thrown. See BigDecimal.mode.
0xff
- EXCEPTION_NaN =
Determines what happens when the result of a computation is not a number (NaN). See BigDecimal.mode.
0x02
- EXCEPTION_INFINITY =
Determines what happens when the result of a computation is infinity. See BigDecimal.mode.
0x01
- EXCEPTION_UNDERFLOW =
Determines what happens when the result of a computation is an underflow (a result too small to be represented). See BigDecimal.mode.
0x04
- EXCEPTION_OVERFLOW =
Determines what happens when the result of a computation is an overflow (a result too large to be represented). See BigDecimal.mode.
0x01
- EXCEPTION_ZERODIVIDE =
Determines what happens when a division by zero is performed. See BigDecimal.mode.
0x10
- ROUND_MODE =
Determines what happens when a result must be rounded in order to fit in the appropriate number of significant digits. See BigDecimal.mode.
0x100
- ROUND_UP =
Indicates that values should be rounded away from zero. See BigDecimal.mode.
1
- ROUND_DOWN =
Indicates that values should be rounded towards zero. See BigDecimal.mode.
2
- ROUND_HALF_UP =
Indicates that digits >= 5 should be rounded up, others rounded down. See BigDecimal.mode.
3
- ROUND_HALF_DOWN =
Indicates that digits >= 6 should be rounded up, others rounded down. See BigDecimal.mode.
4
- ROUND_CEILING =
Round towards +Infinity. See BigDecimal.mode.
5
- ROUND_FLOOR =
Round towards -Infinity. See BigDecimal.mode.
6
- ROUND_HALF_EVEN =
Round towards the even neighbor. See BigDecimal.mode.
7
- SIGN_NaN =
Indicates that a value is not a number. See BigDecimal.sign.
0
- SIGN_POSITIVE_ZERO =
Indicates that a value is +0. See BigDecimal.sign.
1
- SIGN_NEGATIVE_ZERO =
Indicates that a value is -0. See BigDecimal.sign.
-1
- SIGN_POSITIVE_FINITE =
Indicates that a value is positive and finite. See BigDecimal.sign.
2
- SIGN_NEGATIVE_FINITE =
Indicates that a value is negative and finite. See BigDecimal.sign.
-2
- SIGN_POSITIVE_INFINITE =
Indicates that a value is positive and infinite. See BigDecimal.sign.
3
- SIGN_NEGATIVE_INFINITE =
Indicates that a value is negative and infinite. See BigDecimal.sign.
-3
- INFINITY =
Positive infinity value.
f_BigDecimal(1, &arg, rb_cBigDecimal)
- NAN =
‘Not a Number’ value.
f_BigDecimal(1, &arg, rb_cBigDecimal)
Class Method Summary collapse
-
._load(str) ⇒ Object
Internal method used to provide marshalling support.
-
.double_fig ⇒ Object
BigDecimal.double_fig.
- .interpret_loosely(str) ⇒ Object
-
.limit(*args) ⇒ Object
BigDecimal.limit(digits).
-
.mode(*args) ⇒ Object
BigDecimal.mode(mode, value).
-
.save_exception_mode { ... } ⇒ Object
Execute the provided block, but preserve the exception mode.
-
.save_limit { ... } ⇒ Object
Execute the provided block, but preserve the precision limit.
-
.save_rounding_mode { ... } ⇒ Object
Execute the provided block, but preserve the rounding mode.
Instance Method Summary collapse
-
#% ⇒ Object
%: a%b = a - (a.to_f/b).floor * b.
-
#*(r) ⇒ Object
call-seq: mult(value, digits).
-
#**(n) ⇒ Object
Returns the value raised to the power of n.
-
#+(r) ⇒ Object
call-seq: add(value, digits).
-
#+ ⇒ Object
Return self.
-
#-(r) ⇒ Object
a - b -> bigdecimal.
-
#- ⇒ Object
Return the negation of self.
-
#/ ⇒ Object
For c = self/r: with round operation.
-
#<(r) ⇒ Object
a < b.
-
#<=(r) ⇒ Object
a <= b.
-
#<=>(r) ⇒ Object
The comparison operator.
-
#==(r) ⇒ Object
Tests for value equality; returns true if the values are equal.
-
#===(r) ⇒ Object
Tests for value equality; returns true if the values are equal.
-
#>(r) ⇒ Object
a > b.
-
#>=(r) ⇒ Object
a >= b.
-
#_dump ⇒ Object
Method used to provide marshalling support.
-
#abs ⇒ Object
Returns the absolute value, as a BigDecimal.
-
#add(b, n) ⇒ Object
call-seq: add(value, digits).
-
#ceil(*args) ⇒ Object
ceil(n).
- #clone ⇒ Object
-
#coerce(other) ⇒ Object
The coerce method provides support for Ruby type coercion.
-
#div(*args) ⇒ Object
call-seq: div(value, digits) -> bigdecimal or integer.
-
#divmod(r) ⇒ Object
divmod(value).
- #dup ⇒ Object
-
#eql?(r) ⇒ Boolean
Tests for value equality; returns true if the values are equal.
-
#exponent ⇒ Object
Returns the exponent of the BigDecimal number, as an Integer.
-
#finite? ⇒ Boolean
Returns True if the value is finite (not NaN or infinite).
-
#fix ⇒ Object
Return the integer part of the number, as a BigDecimal.
-
#floor(*args) ⇒ Object
floor(n).
-
#frac ⇒ Object
Return the fractional part of the number, as a BigDecimal.
-
#hash ⇒ Object
Creates a hash for this BigDecimal.
-
#infinite? ⇒ Boolean
Returns nil, -1, or 1 depending on whether the value is finite, -Infinity, or Infinity.
-
#inspect ⇒ Object
Returns a string representation of self.
-
#modulo ⇒ Object
%: a%b = a - (a.to_f/b).floor * b.
-
#mult(b, n) ⇒ Object
call-seq: mult(value, digits).
-
#nan? ⇒ Boolean
Returns True if the value is Not a Number.
-
#nonzero? ⇒ Boolean
Returns self if the value is non-zero, nil otherwise.
-
#power(*args) ⇒ Object
power(n) power(n, prec).
-
#precs ⇒ Array
Returns an Array of two Integer values.
-
#quo ⇒ Object
For c = self/r: with round operation.
-
#remainder ⇒ Object
remainder.
-
#round(*args) ⇒ Object
round(n, mode).
-
#sign ⇒ Object
Returns the sign of the value.
-
#split ⇒ Object
Splits a BigDecimal number into four parts, returned as an array of values.
-
#sqrt(nFig) ⇒ Object
sqrt(n).
-
#sub(b, n) ⇒ Object
sub(value, digits) -> bigdecimal.
-
#to_d ⇒ Object
call-seq: a.to_d -> bigdecimal.
-
#to_digits ⇒ Object
call-seq: a.to_digits -> string.
-
#to_f ⇒ Object
Returns a new Float object having approximately the same value as the BigDecimal number.
-
#to_i ⇒ Object
Returns the value as an Integer.
-
#to_int ⇒ Object
Returns the value as an Integer.
-
#to_r ⇒ Object
Converts a BigDecimal to a Rational.
-
#to_s(*args) ⇒ Object
to_s(s).
-
#truncate(*args) ⇒ Object
truncate(n).
-
#zero? ⇒ Boolean
Returns True if the value is zero.
Class Method Details
._load(str) ⇒ Object
Internal method used to provide marshalling support. See the Marshal module.
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# File 'ext/bigdecimal/bigdecimal.c', line 434
static VALUE
BigDecimal_load(VALUE self, VALUE str)
{
ENTER(2);
Real *pv;
unsigned char *pch;
unsigned char ch;
unsigned long m=0;
pch = (unsigned char *)StringValueCStr(str);
/* First get max prec */
while((*pch) != (unsigned char)'\0' && (ch = *pch++) != (unsigned char)':') {
if(!ISDIGIT(ch)) {
rb_raise(rb_eTypeError, "load failed: invalid character in the marshaled string");
}
m = m*10 + (unsigned long)(ch-'0');
}
if (m > VpBaseFig()) m -= VpBaseFig();
GUARD_OBJ(pv, VpNewRbClass(m, (char *)pch, self));
m /= VpBaseFig();
if (m && pv->MaxPrec > m) {
pv->MaxPrec = m+1;
}
return ToValue(pv);
}
|
.double_fig ⇒ Object
BigDecimal.double_fig
The BigDecimal.double_fig class method returns the number of digits a Float number is allowed to have. The result depends upon the CPU and OS in use.
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# File 'ext/bigdecimal/bigdecimal.c', line 344
static VALUE
BigDecimal_double_fig(VALUE self)
{
return INT2FIX(VpDblFig());
}
|
.interpret_loosely(str) ⇒ Object
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# File 'ext/bigdecimal/bigdecimal.c', line 2775
static VALUE
BigDecimal_s_interpret_loosely(VALUE klass, VALUE str)
{
ENTER(1);
char const *c_str;
Real *pv;
c_str = StringValueCStr(str);
GUARD_OBJ(pv, VpAlloc(0, c_str, 0, 1));
pv->obj = TypedData_Wrap_Struct(klass, &BigDecimal_data_type, pv);
RB_OBJ_FREEZE(pv->obj);
return pv->obj;
}
|
.limit(*args) ⇒ Object
BigDecimal.limit(digits)
Limit the number of significant digits in newly created BigDecimal numbers to the specified value. Rounding is performed as necessary, as specified by BigDecimal.mode.
A limit of 0, the default, means no upper limit.
The limit specified by this method takes less priority over any limit specified to instance methods such as ceil, floor, truncate, or round.
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# File 'ext/bigdecimal/bigdecimal.c', line 2801
static VALUE
BigDecimal_limit(int argc, VALUE *argv, VALUE self)
{
VALUE nFig;
VALUE nCur = INT2NUM(VpGetPrecLimit());
if (rb_scan_args(argc, argv, "01", &nFig) == 1) {
int nf;
if (NIL_P(nFig)) return nCur;
nf = NUM2INT(nFig);
if (nf < 0) {
rb_raise(rb_eArgError, "argument must be positive");
}
VpSetPrecLimit(nf);
}
return nCur;
}
|
.mode(*args) ⇒ Object
BigDecimal.mode(mode, value)
Controls handling of arithmetic exceptions and rounding. If no value is supplied, the current value is returned.
Six values of the mode parameter control the handling of arithmetic exceptions:
BigDecimal::EXCEPTION_NaN BigDecimal::EXCEPTION_INFINITY BigDecimal::EXCEPTION_UNDERFLOW BigDecimal::EXCEPTION_OVERFLOW BigDecimal::EXCEPTION_ZERODIVIDE BigDecimal::EXCEPTION_ALL
For each mode parameter above, if the value set is false, computation continues after an arithmetic exception of the appropriate type. When computation continues, results are as follows:
- EXCEPTION_NaN
-
NaN
- EXCEPTION_INFINITY
-
+Infinity or -Infinity
- EXCEPTION_UNDERFLOW
-
0
- EXCEPTION_OVERFLOW
-
+Infinity or -Infinity
- EXCEPTION_ZERODIVIDE
-
+Infinity or -Infinity
One value of the mode parameter controls the rounding of numeric values: BigDecimal::ROUND_MODE. The values it can take are:
- ROUND_UP, :up
-
round away from zero
- ROUND_DOWN, :down, :truncate
-
round towards zero (truncate)
- ROUND_HALF_UP, :half_up, :default
-
round towards the nearest neighbor, unless both neighbors are equidistant, in which case round away from zero. (default)
- ROUND_HALF_DOWN, :half_down
-
round towards the nearest neighbor, unless both neighbors are equidistant, in which case round towards zero.
- ROUND_HALF_EVEN, :half_even, :banker
-
round towards the nearest neighbor, unless both neighbors are equidistant, in which case round towards the even neighbor (Banker’s rounding)
- ROUND_CEILING, :ceiling, :ceil
-
round towards positive infinity (ceil)
- ROUND_FLOOR, :floor
-
round towards negative infinity (floor)
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# File 'ext/bigdecimal/bigdecimal.c', line 582
static VALUE
BigDecimal_mode(int argc, VALUE *argv, VALUE self)
{
VALUE which;
VALUE val;
unsigned long f,fo;
rb_scan_args(argc, argv, "11", &which, &val);
f = (unsigned long)NUM2INT(which);
if (f & VP_EXCEPTION_ALL) {
/* Exception mode setting */
fo = VpGetException();
if (val == Qnil) return INT2FIX(fo);
if (val != Qfalse && val!=Qtrue) {
rb_raise(rb_eArgError, "second argument must be true or false");
return Qnil; /* Not reached */
}
if (f & VP_EXCEPTION_INFINITY) {
VpSetException((unsigned short)((val == Qtrue) ? (fo | VP_EXCEPTION_INFINITY) :
(fo & (~VP_EXCEPTION_INFINITY))));
}
fo = VpGetException();
if (f & VP_EXCEPTION_NaN) {
VpSetException((unsigned short)((val == Qtrue) ? (fo | VP_EXCEPTION_NaN) :
(fo & (~VP_EXCEPTION_NaN))));
}
fo = VpGetException();
if (f & VP_EXCEPTION_UNDERFLOW) {
VpSetException((unsigned short)((val == Qtrue) ? (fo | VP_EXCEPTION_UNDERFLOW) :
(fo & (~VP_EXCEPTION_UNDERFLOW))));
}
fo = VpGetException();
if(f & VP_EXCEPTION_ZERODIVIDE) {
VpSetException((unsigned short)((val == Qtrue) ? (fo | VP_EXCEPTION_ZERODIVIDE) :
(fo & (~VP_EXCEPTION_ZERODIVIDE))));
}
fo = VpGetException();
return INT2FIX(fo);
}
if (VP_ROUND_MODE == f) {
/* Rounding mode setting */
unsigned short sw;
fo = VpGetRoundMode();
if (NIL_P(val)) return INT2FIX(fo);
sw = check_rounding_mode(val);
fo = VpSetRoundMode(sw);
return INT2FIX(fo);
}
rb_raise(rb_eTypeError, "first argument for BigDecimal.mode invalid");
return Qnil;
}
|
.save_exception_mode { ... } ⇒ Object
Execute the provided block, but preserve the exception mode
BigDecimal.save_exception_mode do
BigDecimal.mode(BigDecimal::EXCEPTION_OVERFLOW, false)
BigDecimal.mode(BigDecimal::EXCEPTION_NaN, false)
BigDecimal(BigDecimal('Infinity'))
BigDecimal(BigDecimal('-Infinity'))
BigDecimal(BigDecimal('NaN'))
end
For use with the BigDecimal::EXCEPTION_*
See BigDecimal.mode
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# File 'ext/bigdecimal/bigdecimal.c', line 2860
static VALUE
BigDecimal_save_exception_mode(VALUE self)
{
unsigned short const exception_mode = VpGetException();
int state;
VALUE ret = rb_protect(rb_yield, Qnil, &state);
VpSetException(exception_mode);
if (state) rb_jump_tag(state);
return ret;
}
|
.save_limit { ... } ⇒ Object
Execute the provided block, but preserve the precision limit
BigDecimal.limit(100)
puts BigDecimal.limit
BigDecimal.save_limit do
BigDecimal.limit(200)
puts BigDecimal.limit
end
puts BigDecimal.limit
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# File 'ext/bigdecimal/bigdecimal.c', line 2910
static VALUE
BigDecimal_save_limit(VALUE self)
{
size_t const limit = VpGetPrecLimit();
int state;
VALUE ret = rb_protect(rb_yield, Qnil, &state);
VpSetPrecLimit(limit);
if (state) rb_jump_tag(state);
return ret;
}
|
.save_rounding_mode { ... } ⇒ Object
Execute the provided block, but preserve the rounding mode
BigDecimal.save_rounding_mode do
BigDecimal.mode(BigDecimal::ROUND_MODE, :up)
puts BigDecimal.mode(BigDecimal::ROUND_MODE)
end
For use with the BigDecimal::ROUND_*
See BigDecimal.mode
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# File 'ext/bigdecimal/bigdecimal.c', line 2885
static VALUE
BigDecimal_save_rounding_mode(VALUE self)
{
unsigned short const round_mode = VpGetRoundMode();
int state;
VALUE ret = rb_protect(rb_yield, Qnil, &state);
VpSetRoundMode(round_mode);
if (state) rb_jump_tag(state);
return ret;
}
|
Instance Method Details
#% ⇒ Object
%: a%b = a - (a.to_f/b).floor * b
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# File 'ext/bigdecimal/bigdecimal.c', line 1453
static VALUE
BigDecimal_mod(VALUE self, VALUE r) /* %: a%b = a - (a.to_f/b).floor * b */
{
ENTER(3);
Real *div = NULL, *mod = NULL;
if (BigDecimal_DoDivmod(self, r, &div, &mod)) {
SAVE(div); SAVE(mod);
return ToValue(mod);
}
return DoSomeOne(self, r, '%');
}
|
#*(r) ⇒ Object
call-seq: mult(value, digits)
Multiply by the specified value.
e.g.
c = a.mult(b,n)
c = a * b
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
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# File 'ext/bigdecimal/bigdecimal.c', line 1272
static VALUE
BigDecimal_mult(VALUE self, VALUE r)
{
ENTER(5);
Real *c, *a, *b;
size_t mx;
GUARD_OBJ(a, GetVpValue(self, 1));
if (RB_TYPE_P(r, T_FLOAT)) {
b = GetVpValueWithPrec(r, DBL_DIG+1, 1);
}
else if (RB_TYPE_P(r, T_RATIONAL)) {
b = GetVpValueWithPrec(r, a->Prec*VpBaseFig(), 1);
}
else {
b = GetVpValue(r,0);
}
if (!b) return DoSomeOne(self, r, '*');
SAVE(b);
mx = a->Prec + b->Prec;
GUARD_OBJ(c, VpCreateRbObject(mx *(VpBaseFig() + 1), "0"));
VpMult(c, a, b);
return ToValue(c);
}
|
#**(n) ⇒ Object
Returns the value raised to the power of n.
See BigDecimal#power.
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# File 'ext/bigdecimal/bigdecimal.c', line 2559
static VALUE
BigDecimal_power_op(VALUE self, VALUE exp)
{
return BigDecimal_power(1, &exp, self);
}
|
#+(r) ⇒ Object
call-seq: add(value, digits)
Add the specified value.
e.g.
c = a.add(b,n)
c = a + b
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
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# File 'ext/bigdecimal/bigdecimal.c', line 951
static VALUE
BigDecimal_add(VALUE self, VALUE r)
{
ENTER(5);
Real *c, *a, *b;
size_t mx;
GUARD_OBJ(a, GetVpValue(self, 1));
if (RB_TYPE_P(r, T_FLOAT)) {
b = GetVpValueWithPrec(r, DBL_DIG+1, 1);
}
else if (RB_TYPE_P(r, T_RATIONAL)) {
b = GetVpValueWithPrec(r, a->Prec*VpBaseFig(), 1);
}
else {
b = GetVpValue(r, 0);
}
if (!b) return DoSomeOne(self,r,'+');
SAVE(b);
if (VpIsNaN(b)) return b->obj;
if (VpIsNaN(a)) return a->obj;
mx = GetAddSubPrec(a, b);
if (mx == (size_t)-1L) {
GUARD_OBJ(c,VpCreateRbObject(VpBaseFig() + 1, "0"));
VpAddSub(c, a, b, 1);
}
else {
GUARD_OBJ(c, VpCreateRbObject(mx * (VpBaseFig() + 1), "0"));
if(!mx) {
VpSetInf(c, VpGetSign(a));
}
else {
VpAddSub(c, a, b, 1);
}
}
return ToValue(c);
}
|
#+ ⇒ Object
Return self.
+BigDecimal('5') #=> 0.5e1
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# File 'ext/bigdecimal/bigdecimal.c', line 928
static VALUE
BigDecimal_uplus(VALUE self)
{
return self;
}
|
#-(r) ⇒ Object
a - b -> bigdecimal
Subtract the specified value.
e.g.
c = a - b
The precision of the result value depends on the type of b
.
If b
is a Float, the precision of the result is Float::DIG+1.
If b
is a BigDecimal, the precision of the result is b
‘s precision of internal representation from platform. So, it’s return value is platform dependent.
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# File 'ext/bigdecimal/bigdecimal.c', line 1009
static VALUE
BigDecimal_sub(VALUE self, VALUE r)
{
ENTER(5);
Real *c, *a, *b;
size_t mx;
GUARD_OBJ(a, GetVpValue(self,1));
if (RB_TYPE_P(r, T_FLOAT)) {
b = GetVpValueWithPrec(r, DBL_DIG+1, 1);
}
else if (RB_TYPE_P(r, T_RATIONAL)) {
b = GetVpValueWithPrec(r, a->Prec*VpBaseFig(), 1);
}
else {
b = GetVpValue(r,0);
}
if (!b) return DoSomeOne(self,r,'-');
SAVE(b);
if (VpIsNaN(b)) return b->obj;
if (VpIsNaN(a)) return a->obj;
mx = GetAddSubPrec(a,b);
if (mx == (size_t)-1L) {
GUARD_OBJ(c,VpCreateRbObject(VpBaseFig() + 1, "0"));
VpAddSub(c, a, b, -1);
}
else {
GUARD_OBJ(c,VpCreateRbObject(mx *(VpBaseFig() + 1), "0"));
if (!mx) {
VpSetInf(c,VpGetSign(a));
}
else {
VpAddSub(c, a, b, -1);
}
}
return ToValue(c);
}
|
#- ⇒ Object
Return the negation of self.
-BigDecimal('5') #=> -0.5e1
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# File 'ext/bigdecimal/bigdecimal.c', line 1246
static VALUE
BigDecimal_neg(VALUE self)
{
ENTER(5);
Real *c, *a;
GUARD_OBJ(a, GetVpValue(self, 1));
GUARD_OBJ(c, VpCreateRbObject(a->Prec *(VpBaseFig() + 1), "0"));
VpAsgn(c, a, -1);
return ToValue(c);
}
|
#/ ⇒ Object
For c = self/r: with round operation
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# File 'ext/bigdecimal/bigdecimal.c', line 1341
static VALUE
BigDecimal_div(VALUE self, VALUE r)
/* For c = self/r: with round operation */
{
ENTER(5);
Real *c=NULL, *res=NULL, *div = NULL;
r = BigDecimal_divide(&c, &res, &div, self, r);
if (!NIL_P(r)) return r; /* coerced by other */
SAVE(c); SAVE(res); SAVE(div);
/* a/b = c + r/b */
/* c xxxxx
r 00000yyyyy ==> (y/b)*BASE >= HALF_BASE
*/
/* Round */
if (VpHasVal(div)) { /* frac[0] must be zero for NaN,INF,Zero */
VpInternalRound(c, 0, c->frac[c->Prec-1], (BDIGIT)(VpBaseVal() * (BDIGIT_DBL)res->frac[0] / div->frac[0]));
}
return ToValue(c);
}
|
#<(r) ⇒ Object
a < b
Returns true if a is less than b.
Values may be coerced to perform the comparison (see ==, BigDecimal#coerce).
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# File 'ext/bigdecimal/bigdecimal.c', line 1192
static VALUE
BigDecimal_lt(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '<');
}
|
#<=(r) ⇒ Object
a <= b
Returns true if a is less than or equal to b.
Values may be coerced to perform the comparison (see ==, BigDecimal#coerce).
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# File 'ext/bigdecimal/bigdecimal.c', line 1205
static VALUE
BigDecimal_le(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, 'L');
}
|
#<=>(r) ⇒ Object
The comparison operator. a <=> b is 0 if a == b, 1 if a > b, -1 if a < b.
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# File 'ext/bigdecimal/bigdecimal.c', line 1163
static VALUE
BigDecimal_comp(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '*');
}
|
#==(r) ⇒ Object
Tests for value equality; returns true if the values are equal.
The == and === operators and the eql? method have the same implementation for BigDecimal.
Values may be coerced to perform the comparison:
BigDecimal('1.0') == 1.0 #=> true
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# File 'ext/bigdecimal/bigdecimal.c', line 1179
static VALUE
BigDecimal_eq(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '=');
}
|
#===(r) ⇒ Object
Tests for value equality; returns true if the values are equal.
The == and === operators and the eql? method have the same implementation for BigDecimal.
Values may be coerced to perform the comparison:
BigDecimal('1.0') == 1.0 #=> true
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# File 'ext/bigdecimal/bigdecimal.c', line 1179
static VALUE
BigDecimal_eq(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '=');
}
|
#>(r) ⇒ Object
a > b
Returns true if a is greater than b.
Values may be coerced to perform the comparison (see ==, BigDecimal#coerce).
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# File 'ext/bigdecimal/bigdecimal.c', line 1218
static VALUE
BigDecimal_gt(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '>');
}
|
#>=(r) ⇒ Object
a >= b
Returns true if a is greater than or equal to b.
Values may be coerced to perform the comparison (see ==, BigDecimal#coerce)
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# File 'ext/bigdecimal/bigdecimal.c', line 1231
static VALUE
BigDecimal_ge(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, 'G');
}
|
#_dump ⇒ Object
Method used to provide marshalling support.
inf = BigDecimal('Infinity')
#=> Infinity
BigDecimal._load(inf._dump)
#=> Infinity
See the Marshal module.
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# File 'ext/bigdecimal/bigdecimal.c', line 412
static VALUE
BigDecimal_dump(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
Real *vp;
char *psz;
VALUE dummy;
volatile VALUE dump;
rb_scan_args(argc, argv, "01", &dummy);
GUARD_OBJ(vp,GetVpValue(self, 1));
dump = rb_str_new(0, VpNumOfChars(vp, "E")+50);
psz = RSTRING_PTR(dump);
sprintf(psz, "%"PRIuSIZE":", VpMaxPrec(vp)*VpBaseFig());
VpToString(vp, psz+strlen(psz), 0, 0);
rb_str_resize(dump, strlen(psz));
return dump;
}
|
#abs ⇒ Object
Returns the absolute value, as a BigDecimal.
BigDecimal('5').abs #=> 0.5e1
BigDecimal('-3').abs #=> 0.3e1
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# File 'ext/bigdecimal/bigdecimal.c', line 1722
static VALUE
BigDecimal_abs(VALUE self)
{
ENTER(5);
Real *c, *a;
size_t mx;
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec *(VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpAsgn(c, a, 1);
VpChangeSign(c, 1);
return ToValue(c);
}
|
#add(b, n) ⇒ Object
call-seq: add(value, digits)
Add the specified value.
e.g.
c = a.add(b,n)
c = a + b
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
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# File 'ext/bigdecimal/bigdecimal.c', line 1647
static VALUE
BigDecimal_add2(VALUE self, VALUE b, VALUE n)
{
ENTER(2);
Real *cv;
SIGNED_VALUE mx = GetPrecisionInt(n);
if (mx == 0) return BigDecimal_add(self, b);
else {
size_t pl = VpSetPrecLimit(0);
VALUE c = BigDecimal_add(self, b);
VpSetPrecLimit(pl);
GUARD_OBJ(cv, GetVpValue(c, 1));
VpLeftRound(cv, VpGetRoundMode(), mx);
return ToValue(cv);
}
}
|
#ceil(*args) ⇒ Object
ceil(n)
Return the smallest integer greater than or equal to the value, as a BigDecimal.
BigDecimal(‘3.14159’).ceil #=> 4 BigDecimal(‘-9.1’).ceil #=> -9
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result.
BigDecimal(‘3.14159’).ceil(3) #=> 3.142 BigDecimal(‘13345.234’).ceil(-2) #=> 13400.0
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# File 'ext/bigdecimal/bigdecimal.c', line 1977
static VALUE
BigDecimal_ceil(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
Real *c, *a;
int iLoc;
VALUE vLoc;
size_t mx, pl = VpSetPrecLimit(0);
if (rb_scan_args(argc, argv, "01", &vLoc) == 0) {
iLoc = 0;
} else {
iLoc = NUM2INT(vLoc);
}
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSetPrecLimit(pl);
VpActiveRound(c, a, VP_ROUND_CEIL, iLoc);
if (argc == 0) {
return BigDecimal_to_i(ToValue(c));
}
return ToValue(c);
}
|
#clone ⇒ Object
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# File 'ext/bigdecimal/bigdecimal.c', line 2581
static VALUE
BigDecimal_clone(VALUE self)
{
return self;
}
|
#coerce(other) ⇒ Object
The coerce method provides support for Ruby type coercion. It is not enabled by default.
This means that binary operations like + * / or - can often be performed on a BigDecimal and an object of another type, if the other object can be coerced into a BigDecimal value.
e.g.
a = BigDecimal("1.0")
b = a / 2.0 #=> 0.5
Note that coercing a String to a BigDecimal is not supported by default; it requires a special compile-time option when building Ruby.
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# File 'ext/bigdecimal/bigdecimal.c', line 894
static VALUE
BigDecimal_coerce(VALUE self, VALUE other)
{
ENTER(2);
VALUE obj;
Real *b;
if (RB_TYPE_P(other, T_FLOAT)) {
GUARD_OBJ(b, GetVpValueWithPrec(other, DBL_DIG+1, 1));
obj = rb_assoc_new(ToValue(b), self);
}
else {
if (RB_TYPE_P(other, T_RATIONAL)) {
Real* pv = DATA_PTR(self);
GUARD_OBJ(b, GetVpValueWithPrec(other, pv->Prec*VpBaseFig(), 1));
}
else {
GUARD_OBJ(b, GetVpValue(other, 1));
}
obj = rb_assoc_new(b->obj, self);
}
return obj;
}
|
#div(*args) ⇒ Object
call-seq:
div(value, digits) -> bigdecimal or integer
Divide by the specified value.
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
If digits is 0, the result is the same as for the / operator or #quo.
If digits is not specified, the result is an integer, by analogy with Float#div; see also BigDecimal#divmod.
Examples:
a = BigDecimal("4")
b = BigDecimal("3")
a.div(b, 3) # => 0.133e1
a.div(b, 0) # => 0.1333333333333333333e1
a / b # => 0.1333333333333333333e1
a.quo(b) # => 0.1333333333333333333e1
a.div(b) # => 1
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# File 'ext/bigdecimal/bigdecimal.c', line 1637
static VALUE
BigDecimal_div3(int argc, VALUE *argv, VALUE self)
{
VALUE b,n;
rb_scan_args(argc, argv, "11", &b, &n);
return BigDecimal_div2(self, b, n);
}
|
#divmod(r) ⇒ Object
divmod(value)
Divides by the specified value, and returns the quotient and modulus as BigDecimal numbers. The quotient is rounded towards negative infinity.
For example:
require 'bigdecimal'
a = BigDecimal("42")
b = BigDecimal("9")
q, m = a.divmod(b)
c = q * b + m
a == c #=> true
The quotient q is (a/b).floor, and the modulus is the amount that must be added to q * b to get a.
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# File 'ext/bigdecimal/bigdecimal.c', line 1551
static VALUE
BigDecimal_divmod(VALUE self, VALUE r)
{
ENTER(5);
Real *div = NULL, *mod = NULL;
if (BigDecimal_DoDivmod(self, r, &div, &mod)) {
SAVE(div); SAVE(mod);
return rb_assoc_new(ToValue(div), ToValue(mod));
}
return DoSomeOne(self,r,rb_intern("divmod"));
}
|
#dup ⇒ Object
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# File 'ext/bigdecimal/bigdecimal.c', line 2581
static VALUE
BigDecimal_clone(VALUE self)
{
return self;
}
|
#eql?(r) ⇒ Boolean
Tests for value equality; returns true if the values are equal.
The == and === operators and the eql? method have the same implementation for BigDecimal.
Values may be coerced to perform the comparison:
BigDecimal('1.0') == 1.0 #=> true
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# File 'ext/bigdecimal/bigdecimal.c', line 1179
static VALUE
BigDecimal_eq(VALUE self, VALUE r)
{
return BigDecimalCmp(self, r, '=');
}
|
#exponent ⇒ Object
Returns the exponent of the BigDecimal number, as an Integer.
If the number can be represented as 0.xxxxxx*10**n where xxxxxx is a string of digits with no leading zeros, then n is the exponent.
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# File 'ext/bigdecimal/bigdecimal.c', line 2168
static VALUE
BigDecimal_exponent(VALUE self)
{
ssize_t e = VpExponent10(GetVpValue(self, 1));
return INT2NUM(e);
}
|
#finite? ⇒ Boolean
Returns True if the value is finite (not NaN or infinite).
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# File 'ext/bigdecimal/bigdecimal.c', line 725
static VALUE
BigDecimal_IsFinite(VALUE self)
{
Real *p = GetVpValue(self, 1);
if (VpIsNaN(p)) return Qfalse;
if (VpIsInf(p)) return Qfalse;
return Qtrue;
}
|
#fix ⇒ Object
Return the integer part of the number, as a BigDecimal.
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# File 'ext/bigdecimal/bigdecimal.c', line 1763
static VALUE
BigDecimal_fix(VALUE self)
{
ENTER(5);
Real *c, *a;
size_t mx;
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec *(VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpActiveRound(c, a, VP_ROUND_DOWN, 0); /* 0: round off */
return ToValue(c);
}
|
#floor(*args) ⇒ Object
floor(n)
Return the largest integer less than or equal to the value, as a BigDecimal.
BigDecimal(‘3.14159’).floor #=> 3 BigDecimal(‘-9.1’).floor #=> -10
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result.
BigDecimal(‘3.14159’).floor(3) #=> 3.141 BigDecimal(‘13345.234’).floor(-2) #=> 13300.0
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# File 'ext/bigdecimal/bigdecimal.c', line 1930
static VALUE
BigDecimal_floor(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
Real *c, *a;
int iLoc;
VALUE vLoc;
size_t mx, pl = VpSetPrecLimit(0);
if (rb_scan_args(argc, argv, "01", &vLoc)==0) {
iLoc = 0;
}
else {
iLoc = NUM2INT(vLoc);
}
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSetPrecLimit(pl);
VpActiveRound(c, a, VP_ROUND_FLOOR, iLoc);
#ifdef BIGDECIMAL_DEBUG
VPrint(stderr, "floor: c=%\n", c);
#endif
if (argc == 0) {
return BigDecimal_to_i(ToValue(c));
}
return ToValue(c);
}
|
#frac ⇒ Object
Return the fractional part of the number, as a BigDecimal.
1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 |
# File 'ext/bigdecimal/bigdecimal.c', line 1899
static VALUE
BigDecimal_frac(VALUE self)
{
ENTER(5);
Real *c, *a;
size_t mx;
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpFrac(c, a);
return ToValue(c);
}
|
#hash ⇒ Object
Creates a hash for this BigDecimal.
Two BigDecimals with equal sign, fractional part and exponent have the same hash.
383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 |
# File 'ext/bigdecimal/bigdecimal.c', line 383
static VALUE
BigDecimal_hash(VALUE self)
{
ENTER(1);
Real *p;
st_index_t hash;
GUARD_OBJ(p, GetVpValue(self, 1));
hash = (st_index_t)p->sign;
/* hash!=2: the case for 0(1),NaN(0) or +-Infinity(3) is sign itself */
if(hash == 2 || hash == (st_index_t)-2) {
hash ^= rb_memhash(p->frac, sizeof(BDIGIT)*p->Prec);
hash += p->exponent;
}
return ST2FIX(hash);
}
|
#infinite? ⇒ Boolean
Returns nil, -1, or 1 depending on whether the value is finite, -Infinity, or Infinity.
715 716 717 718 719 720 721 722 |
# File 'ext/bigdecimal/bigdecimal.c', line 715
static VALUE
BigDecimal_IsInfinite(VALUE self)
{
Real *p = GetVpValue(self, 1);
if (VpIsPosInf(p)) return INT2FIX(1);
if (VpIsNegInf(p)) return INT2FIX(-1);
return Qnil;
}
|
#inspect ⇒ Object
Returns a string representation of self.
BigDecimal("1234.5678").inspect
#=> "0.12345678e4"
2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 |
# File 'ext/bigdecimal/bigdecimal.c', line 2180
static VALUE
BigDecimal_inspect(VALUE self)
{
ENTER(5);
Real *vp;
volatile VALUE str;
size_t nc;
GUARD_OBJ(vp, GetVpValue(self, 1));
nc = VpNumOfChars(vp, "E");
str = rb_str_new(0, nc);
VpToString(vp, RSTRING_PTR(str), 0, 0);
rb_str_resize(str, strlen(RSTRING_PTR(str)));
return str;
}
|
#modulo ⇒ Object
%: a%b = a - (a.to_f/b).floor * b
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 |
# File 'ext/bigdecimal/bigdecimal.c', line 1453
static VALUE
BigDecimal_mod(VALUE self, VALUE r) /* %: a%b = a - (a.to_f/b).floor * b */
{
ENTER(3);
Real *div = NULL, *mod = NULL;
if (BigDecimal_DoDivmod(self, r, &div, &mod)) {
SAVE(div); SAVE(mod);
return ToValue(mod);
}
return DoSomeOne(self, r, '%');
}
|
#mult(b, n) ⇒ Object
call-seq: mult(value, digits)
Multiply by the specified value.
e.g.
c = a.mult(b,n)
c = a * b
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 |
# File 'ext/bigdecimal/bigdecimal.c', line 1695
static VALUE
BigDecimal_mult2(VALUE self, VALUE b, VALUE n)
{
ENTER(2);
Real *cv;
SIGNED_VALUE mx = GetPrecisionInt(n);
if (mx == 0) return BigDecimal_mult(self, b);
else {
size_t pl = VpSetPrecLimit(0);
VALUE c = BigDecimal_mult(self, b);
VpSetPrecLimit(pl);
GUARD_OBJ(cv, GetVpValue(c, 1));
VpLeftRound(cv, VpGetRoundMode(), mx);
return ToValue(cv);
}
}
|
#nan? ⇒ Boolean
Returns True if the value is Not a Number.
704 705 706 707 708 709 710 |
# File 'ext/bigdecimal/bigdecimal.c', line 704
static VALUE
BigDecimal_IsNaN(VALUE self)
{
Real *p = GetVpValue(self, 1);
if (VpIsNaN(p)) return Qtrue;
return Qfalse;
}
|
#nonzero? ⇒ Boolean
Returns self if the value is non-zero, nil otherwise.
1153 1154 1155 1156 1157 1158 |
# File 'ext/bigdecimal/bigdecimal.c', line 1153
static VALUE
BigDecimal_nonzero(VALUE self)
{
Real *a = GetVpValue(self, 1);
return VpIsZero(a) ? Qnil : self;
}
|
#power(*args) ⇒ Object
power(n) power(n, prec)
Returns the value raised to the power of n.
Note that n must be an Integer.
Also available as the operator **.
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# File 'ext/bigdecimal/bigdecimal.c', line 2323
static VALUE
BigDecimal_power(int argc, VALUE*argv, VALUE self)
{
ENTER(5);
VALUE vexp, prec;
Real* exp = NULL;
Real *x, *y;
ssize_t mp, ma, n;
SIGNED_VALUE int_exp;
double d;
rb_scan_args(argc, argv, "11", &vexp, &prec);
GUARD_OBJ(x, GetVpValue(self, 1));
n = NIL_P(prec) ? (ssize_t)(x->Prec*VpBaseFig()) : NUM2SSIZET(prec);
if (VpIsNaN(x)) {
y = VpCreateRbObject(n, "0");
RB_GC_GUARD(y->obj);
VpSetNaN(y);
return ToValue(y);
}
retry:
switch (TYPE(vexp)) {
case T_FIXNUM:
break;
case T_BIGNUM:
break;
case T_FLOAT:
d = RFLOAT_VALUE(vexp);
if (d == round(d)) {
if (FIXABLE(d)) {
vexp = LONG2FIX((long)d);
}
else {
vexp = rb_dbl2big(d);
}
goto retry;
}
exp = GetVpValueWithPrec(vexp, DBL_DIG+1, 1);
break;
case T_RATIONAL:
if (is_zero(rb_rational_num(vexp))) {
if (is_positive(vexp)) {
vexp = INT2FIX(0);
goto retry;
}
}
else if (is_one(rb_rational_den(vexp))) {
vexp = rb_rational_num(vexp);
goto retry;
}
exp = GetVpValueWithPrec(vexp, n, 1);
break;
case T_DATA:
if (is_kind_of_BigDecimal(vexp)) {
VALUE zero = INT2FIX(0);
VALUE rounded = BigDecimal_round(1, &zero, vexp);
if (RTEST(BigDecimal_eq(vexp, rounded))) {
vexp = BigDecimal_to_i(vexp);
goto retry;
}
exp = DATA_PTR(vexp);
break;
}
/* fall through */
default:
rb_raise(rb_eTypeError,
"wrong argument type %"PRIsVALUE" (expected scalar Numeric)",
RB_OBJ_CLASSNAME(vexp));
}
if (VpIsZero(x)) {
if (is_negative(vexp)) {
y = VpCreateRbObject(n, "#0");
RB_GC_GUARD(y->obj);
if (BIGDECIMAL_NEGATIVE_P(x)) {
if (is_integer(vexp)) {
if (is_even(vexp)) {
/* (-0) ** (-even_integer) -> Infinity */
VpSetPosInf(y);
}
else {
/* (-0) ** (-odd_integer) -> -Infinity */
VpSetNegInf(y);
}
}
else {
/* (-0) ** (-non_integer) -> Infinity */
VpSetPosInf(y);
}
}
else {
/* (+0) ** (-num) -> Infinity */
VpSetPosInf(y);
}
return ToValue(y);
}
else if (is_zero(vexp)) {
return ToValue(VpCreateRbObject(n, "1"));
}
else {
return ToValue(VpCreateRbObject(n, "0"));
}
}
if (is_zero(vexp)) {
return ToValue(VpCreateRbObject(n, "1"));
}
else if (is_one(vexp)) {
return self;
}
if (VpIsInf(x)) {
if (is_negative(vexp)) {
if (BIGDECIMAL_NEGATIVE_P(x)) {
if (is_integer(vexp)) {
if (is_even(vexp)) {
/* (-Infinity) ** (-even_integer) -> +0 */
return ToValue(VpCreateRbObject(n, "0"));
}
else {
/* (-Infinity) ** (-odd_integer) -> -0 */
return ToValue(VpCreateRbObject(n, "-0"));
}
}
else {
/* (-Infinity) ** (-non_integer) -> -0 */
return ToValue(VpCreateRbObject(n, "-0"));
}
}
else {
return ToValue(VpCreateRbObject(n, "0"));
}
}
else {
y = VpCreateRbObject(n, "0");
if (BIGDECIMAL_NEGATIVE_P(x)) {
if (is_integer(vexp)) {
if (is_even(vexp)) {
VpSetPosInf(y);
}
else {
VpSetNegInf(y);
}
}
else {
/* TODO: support complex */
rb_raise(rb_eMathDomainError,
"a non-integral exponent for a negative base");
}
}
else {
VpSetPosInf(y);
}
return ToValue(y);
}
}
if (exp != NULL) {
return rmpd_power_by_big_decimal(x, exp, n);
}
else if (RB_TYPE_P(vexp, T_BIGNUM)) {
VALUE abs_value = BigDecimal_abs(self);
if (is_one(abs_value)) {
return ToValue(VpCreateRbObject(n, "1"));
}
else if (RTEST(rb_funcall(abs_value, '<', 1, INT2FIX(1)))) {
if (is_negative(vexp)) {
y = VpCreateRbObject(n, "0");
if (is_even(vexp)) {
VpSetInf(y, VpGetSign(x));
}
else {
VpSetInf(y, -VpGetSign(x));
}
return ToValue(y);
}
else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
return ToValue(VpCreateRbObject(n, "-0"));
}
else {
return ToValue(VpCreateRbObject(n, "0"));
}
}
else {
if (is_positive(vexp)) {
y = VpCreateRbObject(n, "0");
if (is_even(vexp)) {
VpSetInf(y, VpGetSign(x));
}
else {
VpSetInf(y, -VpGetSign(x));
}
return ToValue(y);
}
else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
return ToValue(VpCreateRbObject(n, "-0"));
}
else {
return ToValue(VpCreateRbObject(n, "0"));
}
}
}
int_exp = FIX2LONG(vexp);
ma = int_exp;
if (ma < 0) ma = -ma;
if (ma == 0) ma = 1;
if (VpIsDef(x)) {
mp = x->Prec * (VpBaseFig() + 1);
GUARD_OBJ(y, VpCreateRbObject(mp * (ma + 1), "0"));
}
else {
GUARD_OBJ(y, VpCreateRbObject(1, "0"));
}
VpPower(y, x, int_exp);
if (!NIL_P(prec) && VpIsDef(y)) {
VpMidRound(y, VpGetRoundMode(), n);
}
return ToValue(y);
}
|
#precs ⇒ Array
Returns an Array of two Integer values.
The first value is the current number of significant digits in the BigDecimal. The second value is the maximum number of significant digits for the BigDecimal.
BigDecimal('5').precs #=> [9, 18]
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# File 'ext/bigdecimal/bigdecimal.c', line 362
static VALUE
BigDecimal_prec(VALUE self)
{
ENTER(1);
Real *p;
VALUE obj;
GUARD_OBJ(p, GetVpValue(self, 1));
obj = rb_assoc_new(INT2NUM(p->Prec*VpBaseFig()),
INT2NUM(p->MaxPrec*VpBaseFig()));
return obj;
}
|
#quo ⇒ Object
For c = self/r: with round operation
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# File 'ext/bigdecimal/bigdecimal.c', line 1341
static VALUE
BigDecimal_div(VALUE self, VALUE r)
/* For c = self/r: with round operation */
{
ENTER(5);
Real *c=NULL, *res=NULL, *div = NULL;
r = BigDecimal_divide(&c, &res, &div, self, r);
if (!NIL_P(r)) return r; /* coerced by other */
SAVE(c); SAVE(res); SAVE(div);
/* a/b = c + r/b */
/* c xxxxx
r 00000yyyyy ==> (y/b)*BASE >= HALF_BASE
*/
/* Round */
if (VpHasVal(div)) { /* frac[0] must be zero for NaN,INF,Zero */
VpInternalRound(c, 0, c->frac[c->Prec-1], (BDIGIT)(VpBaseVal() * (BDIGIT_DBL)res->frac[0] / div->frac[0]));
}
return ToValue(c);
}
|
#remainder ⇒ Object
remainder
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# File 'ext/bigdecimal/bigdecimal.c', line 1519
static VALUE
BigDecimal_remainder(VALUE self, VALUE r) /* remainder */
{
VALUE f;
Real *d, *rv = 0;
f = BigDecimal_divremain(self, r, &d, &rv);
if (!NIL_P(f)) return f;
return ToValue(rv);
}
|
#round(*args) ⇒ Object
round(n, mode)
Round to the nearest integer (by default), returning the result as a BigDecimal if n is specified, or as an Integer if it isn’t.
BigDecimal(‘3.14159’).round #=> 3 BigDecimal(‘8.7’).round #=> 9 BigDecimal(‘-9.9’).round #=> -10
BigDecimal(‘3.14159’).round(2).class.name #=> “BigDecimal” BigDecimal(‘3.14159’).round.class.name #=> “Integer”
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result.
BigDecimal(‘3.14159’).round(3) #=> 3.142 BigDecimal(‘13345.234’).round(-2) #=> 13300.0
The value of the optional mode argument can be used to determine how rounding is performed; see BigDecimal.mode.
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# File 'ext/bigdecimal/bigdecimal.c', line 1802
static VALUE
BigDecimal_round(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
Real *c, *a;
int iLoc = 0;
VALUE vLoc;
VALUE vRound;
size_t mx, pl;
unsigned short sw = VpGetRoundMode();
switch (rb_scan_args(argc, argv, "02", &vLoc, &vRound)) {
case 0:
iLoc = 0;
break;
case 1:
if (RB_TYPE_P(vLoc, T_HASH)) {
sw = check_rounding_mode_option(vLoc);
}
else {
iLoc = NUM2INT(vLoc);
}
break;
case 2:
iLoc = NUM2INT(vLoc);
if (RB_TYPE_P(vRound, T_HASH)) {
sw = check_rounding_mode_option(vRound);
}
else {
sw = check_rounding_mode(vRound);
}
break;
default:
break;
}
pl = VpSetPrecLimit(0);
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSetPrecLimit(pl);
VpActiveRound(c, a, sw, iLoc);
if (argc == 0) {
return BigDecimal_to_i(ToValue(c));
}
return ToValue(c);
}
|
#sign ⇒ Object
Returns the sign of the value.
Returns a positive value if > 0, a negative value if < 0, and a zero if == 0.
The specific value returned indicates the type and sign of the BigDecimal, as follows:
- BigDecimal::SIGN_NaN
-
value is Not a Number
- BigDecimal::SIGN_POSITIVE_ZERO
-
value is +0
- BigDecimal::SIGN_NEGATIVE_ZERO
-
value is -0
- BigDecimal::SIGN_POSITIVE_INFINITE
-
value is +Infinity
- BigDecimal::SIGN_NEGATIVE_INFINITE
-
value is -Infinity
- BigDecimal::SIGN_POSITIVE_FINITE
-
value is positive
- BigDecimal::SIGN_NEGATIVE_FINITE
-
value is negative
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# File 'ext/bigdecimal/bigdecimal.c', line 2835
static VALUE
BigDecimal_sign(VALUE self)
{ /* sign */
int s = GetVpValue(self, 1)->sign;
return INT2FIX(s);
}
|
#split ⇒ Object
Splits a BigDecimal number into four parts, returned as an array of values.
The first value represents the sign of the BigDecimal, and is -1 or 1, or 0 if the BigDecimal is Not a Number.
The second value is a string representing the significant digits of the BigDecimal, with no leading zeros.
The third value is the base used for arithmetic (currently always 10) as an Integer.
The fourth value is an Integer exponent.
If the BigDecimal can be represented as 0.xxxxxx*10**n, then xxxxxx is the string of significant digits with no leading zeros, and n is the exponent.
From these values, you can translate a BigDecimal to a float as follows:
sign, significant_digits, base, exponent = a.split
f = sign * "0.#{significant_digits}".to_f * (base ** exponent)
(Note that the to_f method is provided as a more convenient way to translate a BigDecimal to a Float.)
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# File 'ext/bigdecimal/bigdecimal.c', line 2131
static VALUE
BigDecimal_split(VALUE self)
{
ENTER(5);
Real *vp;
VALUE obj,str;
ssize_t e, s;
char *psz1;
GUARD_OBJ(vp, GetVpValue(self, 1));
str = rb_str_new(0, VpNumOfChars(vp, "E"));
psz1 = RSTRING_PTR(str);
VpSzMantissa(vp, psz1);
s = 1;
if(psz1[0] == '-') {
size_t len = strlen(psz1 + 1);
memmove(psz1, psz1 + 1, len);
psz1[len] = '\0';
s = -1;
}
if (psz1[0] == 'N') s = 0; /* NaN */
e = VpExponent10(vp);
obj = rb_ary_new2(4);
rb_ary_push(obj, INT2FIX(s));
rb_ary_push(obj, str);
rb_str_resize(str, strlen(psz1));
rb_ary_push(obj, INT2FIX(10));
rb_ary_push(obj, INT2NUM(e));
return obj;
}
|
#sqrt(nFig) ⇒ Object
sqrt(n)
Returns the square root of the value.
Result has at least n significant digits.
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# File 'ext/bigdecimal/bigdecimal.c', line 1744
static VALUE
BigDecimal_sqrt(VALUE self, VALUE nFig)
{
ENTER(5);
Real *c, *a;
size_t mx, n;
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
n = GetPrecisionInt(nFig) + VpDblFig() + BASE_FIG;
if (mx <= n) mx = n;
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSqrt(c, a);
return ToValue(c);
}
|
#sub(b, n) ⇒ Object
sub(value, digits) -> bigdecimal
Subtract the specified value.
e.g.
c = a.sub(b,n)
- digits
-
If specified and less than the number of significant digits of the result, the result is rounded to that number of digits, according to BigDecimal.mode.
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# File 'ext/bigdecimal/bigdecimal.c', line 1677
static VALUE
BigDecimal_sub2(VALUE self, VALUE b, VALUE n)
{
ENTER(2);
Real *cv;
SIGNED_VALUE mx = GetPrecisionInt(n);
if (mx == 0) return BigDecimal_sub(self, b);
else {
size_t pl = VpSetPrecLimit(0);
VALUE c = BigDecimal_sub(self, b);
VpSetPrecLimit(pl);
GUARD_OBJ(cv, GetVpValue(c, 1));
VpLeftRound(cv, VpGetRoundMode(), mx);
return ToValue(cv);
}
}
|
#to_d ⇒ Object
call-seq:
a.to_d -> bigdecimal
Returns self.
require 'bigdecimal/util'
d = BigDecimal("3.14")
d.to_d # => 0.314e1
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# File 'lib/bigdecimal/util.rb', line 106 def to_d self end |
#to_digits ⇒ Object
call-seq:
a.to_digits -> string
Converts a BigDecimal to a String of the form “nnnnnn.mmm”. This method is deprecated; use BigDecimal#to_s(“F”) instead.
require 'bigdecimal/util'
d = BigDecimal("3.14")
d.to_digits # => "3.14"
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# File 'lib/bigdecimal/util.rb', line 86 def to_digits if self.nan? || self.infinite? || self.zero? self.to_s else i = self.to_i.to_s _,f,_,z = self.frac.split i + "." + ("0"*(-z)) + f end end |
#to_f ⇒ Object
Returns a new Float object having approximately the same value as the BigDecimal number. Normal accuracy limits and built-in errors of binary Float arithmetic apply.
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# File 'ext/bigdecimal/bigdecimal.c', line 801
static VALUE
BigDecimal_to_f(VALUE self)
{
ENTER(1);
Real *p;
double d;
SIGNED_VALUE e;
char *buf;
volatile VALUE str;
GUARD_OBJ(p, GetVpValue(self, 1));
if (VpVtoD(&d, &e, p) != 1)
return rb_float_new(d);
if (e > (SIGNED_VALUE)(DBL_MAX_10_EXP+BASE_FIG))
goto overflow;
if (e < (SIGNED_VALUE)(DBL_MIN_10_EXP-BASE_FIG))
goto underflow;
str = rb_str_new(0, VpNumOfChars(p, "E"));
buf = RSTRING_PTR(str);
VpToString(p, buf, 0, 0);
errno = 0;
d = strtod(buf, 0);
if (errno == ERANGE) {
if (d == 0.0) goto underflow;
if (fabs(d) >= HUGE_VAL) goto overflow;
}
return rb_float_new(d);
overflow:
VpException(VP_EXCEPTION_OVERFLOW, "BigDecimal to Float conversion", 0);
if (BIGDECIMAL_NEGATIVE_P(p))
return rb_float_new(VpGetDoubleNegInf());
else
return rb_float_new(VpGetDoublePosInf());
underflow:
VpException(VP_EXCEPTION_UNDERFLOW, "BigDecimal to Float conversion", 0);
if (BIGDECIMAL_NEGATIVE_P(p))
return rb_float_new(-0.0);
else
return rb_float_new(0.0);
}
|
#to_i ⇒ Object
Returns the value as an Integer.
If the BigDecimal is infinity or NaN, raises FloatDomainError.
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# File 'ext/bigdecimal/bigdecimal.c', line 754
static VALUE
BigDecimal_to_i(VALUE self)
{
ENTER(5);
ssize_t e, nf;
Real *p;
GUARD_OBJ(p, GetVpValue(self, 1));
BigDecimal_check_num(p);
e = VpExponent10(p);
if (e <= 0) return INT2FIX(0);
nf = VpBaseFig();
if (e <= nf) {
return LONG2NUM((long)(VpGetSign(p) * (BDIGIT_DBL_SIGNED)p->frac[0]));
}
else {
VALUE a = BigDecimal_split(self);
VALUE digits = RARRAY_AREF(a, 1);
VALUE numerator = rb_funcall(digits, rb_intern("to_i"), 0);
VALUE ret;
ssize_t dpower = e - (ssize_t)RSTRING_LEN(digits);
if (BIGDECIMAL_NEGATIVE_P(p)) {
numerator = rb_funcall(numerator, '*', 1, INT2FIX(-1));
}
if (dpower < 0) {
ret = rb_funcall(numerator, rb_intern("div"), 1,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(-dpower)));
}
else {
ret = rb_funcall(numerator, '*', 1,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(dpower)));
}
if (RB_TYPE_P(ret, T_FLOAT)) {
rb_raise(rb_eFloatDomainError, "Infinity");
}
return ret;
}
}
|
#to_int ⇒ Object
Returns the value as an Integer.
If the BigDecimal is infinity or NaN, raises FloatDomainError.
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# File 'ext/bigdecimal/bigdecimal.c', line 754
static VALUE
BigDecimal_to_i(VALUE self)
{
ENTER(5);
ssize_t e, nf;
Real *p;
GUARD_OBJ(p, GetVpValue(self, 1));
BigDecimal_check_num(p);
e = VpExponent10(p);
if (e <= 0) return INT2FIX(0);
nf = VpBaseFig();
if (e <= nf) {
return LONG2NUM((long)(VpGetSign(p) * (BDIGIT_DBL_SIGNED)p->frac[0]));
}
else {
VALUE a = BigDecimal_split(self);
VALUE digits = RARRAY_AREF(a, 1);
VALUE numerator = rb_funcall(digits, rb_intern("to_i"), 0);
VALUE ret;
ssize_t dpower = e - (ssize_t)RSTRING_LEN(digits);
if (BIGDECIMAL_NEGATIVE_P(p)) {
numerator = rb_funcall(numerator, '*', 1, INT2FIX(-1));
}
if (dpower < 0) {
ret = rb_funcall(numerator, rb_intern("div"), 1,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(-dpower)));
}
else {
ret = rb_funcall(numerator, '*', 1,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(dpower)));
}
if (RB_TYPE_P(ret, T_FLOAT)) {
rb_raise(rb_eFloatDomainError, "Infinity");
}
return ret;
}
}
|
#to_r ⇒ Object
Converts a BigDecimal to a Rational.
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# File 'ext/bigdecimal/bigdecimal.c', line 848
static VALUE
BigDecimal_to_r(VALUE self)
{
Real *p;
ssize_t sign, power, denomi_power;
VALUE a, digits, numerator;
p = GetVpValue(self, 1);
BigDecimal_check_num(p);
sign = VpGetSign(p);
power = VpExponent10(p);
a = BigDecimal_split(self);
digits = RARRAY_AREF(a, 1);
denomi_power = power - RSTRING_LEN(digits);
numerator = rb_funcall(digits, rb_intern("to_i"), 0);
if (sign < 0) {
numerator = rb_funcall(numerator, '*', 1, INT2FIX(-1));
}
if (denomi_power < 0) {
return rb_Rational(numerator,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(-denomi_power)));
}
else {
return rb_Rational1(rb_funcall(numerator, '*', 1,
rb_funcall(INT2FIX(10), rb_intern("**"), 1,
INT2FIX(denomi_power))));
}
}
|
#to_s(*args) ⇒ Object
to_s(s)
Converts the value to a string.
The default format looks like 0.xxxxEnn.
The optional parameter s consists of either an integer; or an optional ‘+’ or ‘ ’, followed by an optional number, followed by an optional ‘E’ or ‘F’.
If there is a ‘+’ at the start of s, positive values are returned with a leading ‘+’.
A space at the start of s returns positive values with a leading space.
If s contains a number, a space is inserted after each group of that many fractional digits.
If s ends with an ‘E’, engineering notation (0.xxxxEnn) is used.
If s ends with an ‘F’, conventional floating point notation is used.
Examples:
BigDecimal('-123.45678901234567890').to_s('5F')
#=> '-123.45678 90123 45678 9'
BigDecimal('123.45678901234567890').to_s('+8F')
#=> '+123.45678901 23456789'
BigDecimal('123.45678901234567890').to_s(' F')
#=> ' 123.4567890123456789'
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# File 'ext/bigdecimal/bigdecimal.c', line 2036
static VALUE
BigDecimal_to_s(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
int fmt = 0; /* 0: E format, 1: F format */
int fPlus = 0; /* 0: default, 1: set ' ' before digits, 2: set '+' before digits. */
Real *vp;
volatile VALUE str;
char *psz;
char ch;
size_t nc, mc = 0;
SIGNED_VALUE m;
VALUE f;
GUARD_OBJ(vp, GetVpValue(self, 1));
if (rb_scan_args(argc, argv, "01", &f) == 1) {
if (RB_TYPE_P(f, T_STRING)) {
psz = StringValueCStr(f);
if (*psz == ' ') {
fPlus = 1;
psz++;
}
else if (*psz == '+') {
fPlus = 2;
psz++;
}
while ((ch = *psz++) != 0) {
if (ISSPACE(ch)) {
continue;
}
if (!ISDIGIT(ch)) {
if (ch == 'F' || ch == 'f') {
fmt = 1; /* F format */
}
break;
}
mc = mc*10 + ch - '0';
}
}
else {
m = NUM2INT(f);
if (m <= 0) {
rb_raise(rb_eArgError, "argument must be positive");
}
mc = (size_t)m;
}
}
if (fmt) {
nc = VpNumOfChars(vp, "F");
}
else {
nc = VpNumOfChars(vp, "E");
}
if (mc > 0) {
nc += (nc + mc - 1) / mc + 1;
}
str = rb_str_new(0, nc);
psz = RSTRING_PTR(str);
if (fmt) {
VpToFString(vp, psz, mc, fPlus);
}
else {
VpToString (vp, psz, mc, fPlus);
}
rb_str_resize(str, strlen(psz));
return str;
}
|
#truncate(*args) ⇒ Object
truncate(n)
Truncate to the nearest integer (by default), returning the result as a BigDecimal.
BigDecimal(‘3.14159’).truncate #=> 3 BigDecimal(‘8.7’).truncate #=> 8 BigDecimal(‘-9.9’).truncate #=> -9
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result.
BigDecimal(‘3.14159’).truncate(3) #=> 3.141 BigDecimal(‘13345.234’).truncate(-2) #=> 13300.0
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# File 'ext/bigdecimal/bigdecimal.c', line 1870
static VALUE
BigDecimal_truncate(int argc, VALUE *argv, VALUE self)
{
ENTER(5);
Real *c, *a;
int iLoc;
VALUE vLoc;
size_t mx, pl = VpSetPrecLimit(0);
if (rb_scan_args(argc, argv, "01", &vLoc) == 0) {
iLoc = 0;
}
else {
iLoc = NUM2INT(vLoc);
}
GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec * (VpBaseFig() + 1);
GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSetPrecLimit(pl);
VpActiveRound(c, a, VP_ROUND_DOWN, iLoc); /* 0: truncate */
if (argc == 0) {
return BigDecimal_to_i(ToValue(c));
}
return ToValue(c);
}
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#zero? ⇒ Boolean
Returns True if the value is zero.
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# File 'ext/bigdecimal/bigdecimal.c', line 1145
static VALUE
BigDecimal_zero(VALUE self)
{
Real *a = GetVpValue(self, 1);
return VpIsZero(a) ? Qtrue : Qfalse;
}
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