Class: SVG::Graph::TimeSeries

Inherits:
Plot show all
Defined in:
lib/SVG/Graph/TimeSeries.rb

Overview

For creating SVG plots of scalar temporal data

Synopsis

require 'SVG/Graph/TimeSeries'

# Data sets are x,y pairs
projection = ["6/17/72", 11,    "1/11/72", 7,    "4/13/04", 11,
             "9/11/01", 9,    "9/1/85", 2,    "9/1/88", 1,    "1/15/95", 13]
actual = ["8/1/73", 18,    "3/1/77", 15,    "10/1/98", 4,
          "5/1/02", 14,    "3/1/95", 6,    "8/1/91", 12,    "12/1/87", 6,
          "5/1/84", 17,    "10/1/80", 12]

title = "Ice Cream Cone Consumption"

graph = SVG::Graph::TimeSeries.new( {
  :width => 640,
  :height => 480,
  :graph_title => title,
  :show_graph_title => true,
  :no_css => true,
  :key => true,
  :scale_x_integers => true,
  :scale_y_integers => true,
  :min_x_value => 0,  # Integer, Time, or parseable by DateTime#parse
  :min_y_value => 0,  # Integer, Time, or parseable by DateTime#parse
  :show_data_values => true,
  :show_x_guidelines => true,
  :show_x_title => true,
  :x_title => "Time",
  :show_y_title => true,
  :y_title => "Ice Cream Cones",
  :y_title_text_direction => :bt,
  :stagger_x_labels => true,
  :x_label_format => "%m/%d/%y",
})

graph.add_data({
  :data => projection,
  :title => 'Projected',
  :template => '%d/%m/%y'
})

graph.add_data({
  :data => actual,
  :title => 'Actual',
  :template => '%d/%m/%y'
})

print graph.burn()

Description

Produces a graph of temporal scalar data.

Examples

www.germane-software/repositories/public/SVG/test/timeseries.rb

Notes

The default stylesheet handles upto 10 data sets, if you use more you must create your own stylesheet and add the additional settings for the extra data sets. You will know if you go over 10 data sets as they will have no style and be in black.

Unlike the other types of charts, data sets must contain x,y pairs:

[ "12:30", 2 ]          # A data set with 1 point: ("12:30",2)
[ "01:00",2, "14:20",6] # A data set with 2 points: ("01:00",2) and 
                        #                           ("14:20",6)

Note that multiple data sets within the same chart can differ in length, and that the data in the datasets needn’t be in order; they will be ordered by the plot along the X-axis.

The dates must be parseable by DateTime#parse or DateTime#strptime, but otherwise can be any order of magnitude (seconds within the hour, or years)

See also

  • SVG::Graph::Graph

  • SVG::Graph::BarHorizontal

  • SVG::Graph::Bar

  • SVG::Graph::Line

  • SVG::Graph::Pie

  • SVG::Graph::Plot

Author

Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom>

Copyright 2004 Sean E. Russell This software is available under the Ruby license

Constant Summary

Constants included from SVG::Graph

VERSION

Instance Attribute Summary collapse

Attributes inherited from Plot

#area_fill, #max_x_value, #max_y_value, #min_x_value, #min_y_value, #round_popups, #scale_x_divisions, #scale_x_integers, #scale_y_divisions, #scale_y_integers, #show_data_points, #show_lines

Instance Method Summary collapse

Instance Attribute Details

The formatting used for the popups. See x_label_format



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# File 'lib/SVG/Graph/TimeSeries.rb', line 131

def popup_format
  @popup_format
end

#timescale_divisions ⇒ Object

Use this to set the spacing between dates on the axis. The value must be of the form “d+ ?(days|weeks|months|years|hours|minutes|seconds)?”

EG:

graph.timescale_divisions = "2 weeks"

will cause the chart to try to divide the X axis up into segments of two week periods.



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# File 'lib/SVG/Graph/TimeSeries.rb', line 129

def timescale_divisions
  @timescale_divisions
end

#x_label_format ⇒ Object

The format string used to format the X axis labels. See Time::strformat, default: ‘%Y-%m-%d %H:%M:%S’



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# File 'lib/SVG/Graph/TimeSeries.rb', line 118

def x_label_format
  @x_label_format
end

Instance Method Details

#add_data(data) ⇒ Object

Add data to the plot.

d1 = [ "12:30", 2 ]          # A data set with 1 point: ("12:30",2)
d2 = [ "01:00",2, "14:20",6] # A data set with 2 points: ("01:00",2) and 
                             #                           ("14:20",6)  
graph.add_data( 
  :data => d1,
  :title => 'One',
  :template => '%H:%M'  #template is optional
)
graph.add_data(
  :data => d2,
  :title => 'Two',
  :template => '%H:%M'
)

Note that the data must be in time,value pairs. The time may be any date in a format that is parseable by ParseDate, a Time object, or a number of seconds after the unix epoch.



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# File 'lib/SVG/Graph/TimeSeries.rb', line 152

def add_data data
  data[:data].each_index do |i|
    data[:data][i] = parse_time(data[:data][i], data[:template]).to_i if i % 2 == 0  # only even indices are time, odd indices are values
  end
  super(data)
end

#set_defaults ⇒ Object

In addition to the defaults set by Graph::initialize and Plot::set_defaults, sets:

x_label_format

‘%Y-%m-%d %H:%M:%S’

popup_format

‘%Y-%m-%d %H:%M:%S’



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# File 'lib/SVG/Graph/TimeSeries.rb', line 107

def set_defaults
  super
  init_with(
    #:max_time_span     => '',
    :x_label_format     => '%Y-%m-%d %H:%M:%S',
    :popup_format       => '%Y-%m-%d %H:%M:%S',
  )
end