Class: NumRu::GPhys::Grib

Inherits:

Object

• Object
• NumRu::GPhys::Grib

Defined in:

lib/numru/gphys/grib.rb

Overview

GribUtils

Defined Under Namespace

Classes: GribBDS, GribBMS, GribES, GribGDS, GribIS, GribPDS, GribSegment

Class Method Summary

• .create(fname) ⇒ Object
• .is_a_Grib?(fname) ⇒ Boolean
• .open(fname) ⇒ Object

Instance Method Summary

• #att(name) ⇒ Object
• #att_names ⇒ Object
• #close ⇒ Object
• #def_var(name) ⇒ Object
• #inspect ⇒ Object
• #parse(mbio) ⇒ Object
• #path ⇒ Object
• #var(name) ⇒ Object
• #var_names ⇒ Object
• #write ⇒ Object

Class Method Details

.create(fname) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1422

def create(fname)
  Grib.new(fname,"w")
end

.is_a_Grib?(fname) ⇒ Boolean

Returns:

• (Boolean)

# File 'lib/numru/gphys/grib.rb', line 1404

def is_a_Grib?(fname)
  file = nil
  begin
    file = File.open(fname,"rb")
    is = (file.read(4) == "GRIB")
  ensure
    file.close if file
  end
  return defined?(is) && is
end

.open(fname) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1414

def open(fname)
  #warn "This grib library is obsoleted."
  #warn "Use http://ruby.gfd-dennou.org/products/rb-grib/ instead."
  f = Grib.new(fname,"r")
  mbio = NumRu::MultibitIO.new(fname)
  f.parse(mbio)
  return f
end

Instance Method Details

#att(name) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1476

def att(name)
  @attr[name]
end

#att_names ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1473

def att_names
  @attr.keys
end

#close ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1427

def close
  @grib_vars = nil
  @vars = nil
  @attr = nil
  @file.close
end

#def_var(name) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1461

def def_var(name)
  until @file.stat.writable?
    raise("File #{@file.path} is not writable.")
  end
  if !String===name
    raise "def_var(String)"
  end
  raise "#{name} is already defined" if @vars.has_key?(name)
  var = GribVar.new(@file,name)
  @vars[name] = var
  return var
end

#inspect ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1557

def inspect
  "Grib: #{path}"
end

#parse(mbio) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1433

def parse(mbio)
  @file.rewind
  while true
    @file.read(1)=="\000" && next
    @file.eof? && break
    @file.seek(-1, ::IO::SEEK_CUR)
    sgm = GribSegment.parse(@file, mbio)
    return nil unless sgm
    name = sgm.pds.sname
    if @vars.has_key?(name)
      @vars[name].push(sgm)
    else
      @vars[name] = [sgm]
    end
  end
  return self
end

#path ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1450

def path
  @file.path
end

#var(name) ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1456

def var(name)
  var = @vars[name]
  return nil if var.nil?
  return GribVar.parse(self,var,name)
end

#var_names ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1453

def var_names
  @vars.keys
end

#write ⇒ Object

# File 'lib/numru/gphys/grib.rb', line 1479

def write
  iz=0
  it=0
  izmax = 0
  vn = var_names
  @file.rewind
  while (vn.length>0)
    vn.dup.each{|name|
      var = @vars[name]
      sgm = nil
      if var.rank==2
        sgm = GribSegment.create(@file)
        val = [var.get,var.att("long_name"),var.att("units")]
        z = var.att("level")
        t = var.att("time")
        vn.delete(name)
      elsif var.rank==4
        sha = var.shape
        izmax < sha[2] && izmax = sha[2]
        if iz<sha[2]&&it<sha[3]
          sgm = GribSegment.create(@file)
          val = [var[true,true,iz,it],var.att("long_name"),var.att("units")]
          zd = var.dim(2)
          zv = zd.get
          if Array===zv
            zv = zv.collect{|a| a["value"][iz] }
          else
            zv = [zv[iz]]
          end
          z = [zd.att("long_name"), zv]
          t = var.dim(3)[it]
        elsif it==sha[3]
          vn.delete(name)
        end
      elsif !var.dim_names.include?("time")
        sha = var.shape
        izmax < sha[2] && izmax = sha[2]
        if iz<sha[2]
          sgm = GribSegment.create(@file)
          val = [var[true,true,iz],var.att("long_name"),var.att("units")]
          zd = var.dim(2)
          zv = zd.get
          if Array===zv
            zv = zv.collect{|a| a["value"][iz] }
          else
            zv = [zv[iz]]
          end
          z = [zd.att("long_name"), zv]
          t = var.att("time")
        end
        vn.delete(name) if iz==sha[2]-1
      else
        sha = var.shape
        if it<sha[2]
          sgm = GribSegment.create(@file)
          val = [var[true,true,it],var.att("long_name"),var.att("units")]
          z = var.att("level")
          t = var.dim(2)[it]
        else
          vn.delete(name)
        end
      end
      if sgm
        sgm.set_xy(var.dim(0),var.dim(1))
        sgm.set_level(z)
        sgm.set_time(t)
        sgm.set_var(*val)
        sgm.write
      end
      if iz==izmax-1
        iz = 0
        it += 1
      else
        iz += 1
      end
    }
  end
end