lucene/client/ruby/flare/vendor/plugins/sparklines/lib/sparklines.rb

583 lines
18 KiB
Ruby

require 'rubygems'
require 'RMagick'
=begin rdoc
A library for generating small unmarked graphs (sparklines).
Can be used to write an image to a file or make a web service with Rails or other Ruby CGI apps.
Idea and much of the outline for the source lifted directly from {Joe Gregorio's Python Sparklines web service script}[http://bitworking.org/projects/sparklines].
Requires the RMagick image library.
==Authors
{Dan Nugent}[mailto:nugend@gmail.com] Original port from Python Sparklines library.
{Geoffrey Grosenbach}[mailto:boss@topfunky.com] -- http://nubyonrails.topfunky.com
-- Conversion to module and further maintenance.
==General Usage and Defaults
To use in a script:
require 'rubygems'
require 'sparklines'
Sparklines.plot([1,25,33,46,89,90,85,77,42],
:type => 'discrete',
:height => 20)
An image blob will be returned which you can print, write to STDOUT, etc.
For use with Ruby on Rails, see the sparklines plugin:
http://nubyonrails.com/pages/sparklines
In your view, call it like this:
<%= sparkline_tag [1,2,3,4,5,6] %>
Or specify details:
<%= sparkline_tag [1,2,3,4,5,6],
:type => 'discrete',
:height => 10,
:upper => 80,
:above_color => 'green',
:below_color => 'blue' %>
Graph types:
area
discrete
pie
smooth
bar
whisker
General Defaults:
:type => 'smooth'
:height => 14px
:upper => 50
:above_color => 'red'
:below_color => 'grey'
:background_color => 'white'
:line_color => 'lightgrey'
==License
Licensed under the MIT license.
=end
class Sparklines
VERSION = '0.4.1'
@@label_margin = 5.0
@@pointsize = 10.0
class << self
# Does the actual plotting of the graph.
# Calls the appropriate subclass based on the :type argument.
# Defaults to 'smooth'
def plot(data=[], options={})
defaults = {
:type => 'smooth',
:height => 14,
:upper => 50,
:diameter => 20,
:step => 2,
:line_color => 'lightgrey',
:above_color => 'red',
:below_color => 'grey',
:background_color => 'white',
:share_color => 'red',
:remain_color => 'lightgrey',
:min_color => 'blue',
:max_color => 'green',
:last_color => 'red',
:has_min => false,
:has_max => false,
:has_last => false,
:label => nil
}
# HACK for HashWithIndifferentAccess
options_sym = Hash.new
options.keys.each do |key|
options_sym[key.to_sym] = options[key]
end
options_sym = defaults.merge(options_sym)
# Call the appropriate method for actual plotting.
sparkline = self.new(data, options_sym)
if %w(area bar pie smooth discrete whisker).include? options_sym[:type]
sparkline.send options_sym[:type]
else
sparkline.plot_error options_sym
end
end
# Writes a graph to disk with the specified filename, or "sparklines.png"
def plot_to_file(filename="sparklines.png", data=[], options={})
File.open( filename, 'wb' ) do |png|
png << self.plot( data, options)
end
end
end # class methods
def initialize(data=[], options={})
@data = Array(data)
@options = options
normalize_data
end
##
# Creates a continuous area sparkline. Relevant options.
#
# :step - An integer that determines the distance between each point on the sparkline. Defaults to 2.
#
# :height - An integer that determines what the height of the sparkline will be. Defaults to 14
#
# :upper - An integer that determines the threshold for colorization purposes. Any value less than upper will be colored using below_color, anything above and equal to upper will use above_color. Defaults to 50.
#
# :has_min - Determines whether a dot will be drawn at the lowest value or not. Defaults to false.
#
# :has_max - Determines whether a dot will be drawn at the highest value or not. Defaults to false.
#
# :has_last - Determines whether a dot will be drawn at the last value or not. Defaults to false.
#
# :min_color - A string or color code representing the color that the dot drawn at the smallest value will be displayed as. Defaults to blue.
#
# :max_color - A string or color code representing the color that the dot drawn at the largest value will be displayed as. Defaults to green.
#
# :last_color - A string or color code representing the color that the dot drawn at the last value will be displayed as. Defaults to red.
#
# :above_color - A string or color code representing the color to draw values above or equal the upper value. Defaults to red.
#
# :below_color - A string or color code representing the color to draw values below the upper value. Defaults to gray.
def area
step = @options[:step].to_i
height = @options[:height].to_i
background_color = @options[:background_color]
create_canvas((@norm_data.size - 1) * step + 4, height, background_color)
upper = @options[:upper].to_i
has_min = @options[:has_min]
has_max = @options[:has_max]
has_last = @options[:has_last]
min_color = @options[:min_color]
max_color = @options[:max_color]
last_color = @options[:last_color]
below_color = @options[:below_color]
above_color = @options[:above_color]
coords = [[0,(height - 3 - upper/(101.0/(height-4)))]]
i=0
@norm_data.each do |r|
coords.push [(2 + i), (height - 3 - r/(101.0/(height-4)))]
i += step
end
coords.push [(@norm_data.size - 1) * step + 4, (height - 3 - upper/(101.0/(height-4)))]
# TODO Refactor! Should take a block and do both.
#
# Block off the bottom half of the image and draw the sparkline
@draw.fill(above_color)
@draw.define_clip_path('top') do
@draw.rectangle(0,0,(@norm_data.size - 1) * step + 4,(height - 3 - upper/(101.0/(height-4))))
end
@draw.clip_path('top')
@draw.polygon *coords.flatten
# Block off the top half of the image and draw the sparkline
@draw.fill(below_color)
@draw.define_clip_path('bottom') do
@draw.rectangle(0,(height - 3 - upper/(101.0/(height-4))),(@norm_data.size - 1) * step + 4,height)
end
@draw.clip_path('bottom')
@draw.polygon *coords.flatten
# The sparkline looks kinda nasty if either the above_color or below_color gets the center line
@draw.fill('black')
@draw.line(0,(height - 3 - upper/(101.0/(height-4))),(@norm_data.size - 1) * step + 4,(height - 3 - upper/(101.0/(height-4))))
# After the parts have been masked, we need to let the whole canvas be drawable again
# so a max dot can be displayed
@draw.define_clip_path('all') do
@draw.rectangle(0,0,@canvas.columns,@canvas.rows)
end
@draw.clip_path('all')
drawbox(coords[@norm_data.index(@norm_data.min)+1], 1, min_color) if has_min == true
drawbox(coords[@norm_data.index(@norm_data.max)+1], 1, max_color) if has_max == true
drawbox(coords[-2], 1, last_color) if has_last == true
@draw.draw(@canvas)
@canvas.to_blob
end
##
# A bar graph.
def bar
step = @options[:step].to_i
height = @options[:height].to_f
background_color = @options[:background_color]
create_canvas(@norm_data.length * step + 2, height, background_color)
upper = @options[:upper].to_i
below_color = @options[:below_color]
above_color = @options[:above_color]
i = 1
@norm_data.each_with_index do |r, index|
color = (r >= upper) ? above_color : below_color
@draw.stroke('transparent')
@draw.fill(color)
@draw.rectangle( i, @canvas.rows,
i + step - 2, @canvas.rows - ( (r / @maximum_value) * @canvas.rows) )
i += step
end
@draw.draw(@canvas)
@canvas.to_blob
end
##
# Creates a discretized sparkline
#
# :height - An integer that determines what the height of the sparkline will be. Defaults to 14
#
# :upper - An integer that determines the threshold for colorization purposes. Any value less than upper will be colored using below_color, anything above and equal to upper will use above_color. Defaults to 50.
#
# :above_color - A string or color code representing the color to draw values above or equal the upper value. Defaults to red.
#
# :below_color - A string or color code representing the color to draw values below the upper value. Defaults to gray.
def discrete
height = @options[:height].to_i
upper = @options[:upper].to_i
background_color = @options[:background_color]
step = @options[:step].to_i
create_canvas(@norm_data.size * step - 1, height, background_color)
below_color = @options[:below_color]
above_color = @options[:above_color]
i = 0
@norm_data.each do |r|
color = (r >= upper) ? above_color : below_color
@draw.stroke(color)
@draw.line(i, (@canvas.rows - r/(101.0/(height-4))-4).to_i,
i, (@canvas.rows - r/(101.0/(height-4))).to_i)
i += step
end
@draw.draw(@canvas)
@canvas.to_blob
end
##
# Creates a pie-chart sparkline
#
# :diameter - An integer that determines what the size of the sparkline will be. Defaults to 20
#
# :share_color - A string or color code representing the color to draw the share of the pie represented by percent. Defaults to red.
#
# :remain_color - A string or color code representing the color to draw the pie not taken by the share color. Defaults to lightgrey.
def pie
diameter = @options[:diameter].to_i
background_color = @options[:background_color]
create_canvas(diameter, diameter, background_color)
share_color = @options[:share_color]
remain_color = @options[:remain_color]
percent = @norm_data[0]
# Adjust the radius so there's some edge left in the pie
r = diameter/2.0 - 2
@draw.fill(remain_color)
@draw.ellipse(r + 2, r + 2, r , r , 0, 360)
@draw.fill(share_color)
# Special exceptions
if percent == 0
# For 0% return blank
@draw.draw(@canvas)
return @canvas.to_blob
elsif percent == 100
# For 100% just draw a full circle
@draw.ellipse(r + 2, r + 2, r , r , 0, 360)
@draw.draw(@canvas)
return @canvas.to_blob
end
# Okay, this part is as confusing as hell, so pay attention:
# This line determines the horizontal portion of the point on the circle where the X-Axis
# should end. It's caculated by taking the center of the on-image circle and adding that
# to the radius multiplied by the formula for determinig the point on a unit circle that a
# angle corresponds to. 3.6 * percent gives us that angle, but it's in degrees, so we need to
# convert, hence the muliplication by Pi over 180
arc_end_x = r + 2 + (r * Math.cos((3.6 * percent)*(Math::PI/180)))
# The same goes for here, except it's the vertical point instead of the horizontal one
arc_end_y = r + 2 + (r * Math.sin((3.6 * percent)*(Math::PI/180)))
# Because the SVG path format is seriously screwy, we need to set the large-arc-flag to 1
# if the angle of an arc is greater than 180 degrees. I have no idea why this is, but it is.
percent > 50? large_arc_flag = 1: large_arc_flag = 0
# This is also confusing
# M tells us to move to an absolute point on the image. We're moving to the center of the pie
# h tells us to move to a relative point. We're moving to the right edge of the circle.
# A tells us to start an absolute elliptical arc. The first two values are the radii of the ellipse
# the third value is the x-axis-rotation (how to rotate the ellipse if we wanted to [could have some fun
# with randomizing that maybe), the fourth value is our large-arc-flag, the fifth is the sweep-flag,
# (again, confusing), the sixth and seventh values are the end point of the arc which we calculated previously
# More info on the SVG path string format at: http://www.w3.org/TR/SVG/paths.html
path = "M#{r + 2},#{r + 2} h#{r} A#{r},#{r} 0 #{large_arc_flag},1 #{arc_end_x},#{arc_end_y} z"
@draw.path(path)
@draw.draw(@canvas)
@canvas.to_blob
end
##
# Creates a smooth sparkline.
#
# :step - An integer that determines the distance between each point on the sparkline. Defaults to 2.
#
# :height - An integer that determines what the height of the sparkline will be. Defaults to 14
#
# :has_min - Determines whether a dot will be drawn at the lowest value or not. Defaults to false.
#
# :has_max - Determines whether a dot will be drawn at the highest value or not. Defaults to false.
#
# :has_last - Determines whether a dot will be drawn at the last value or not. Defaults to false.
#
# :min_color - A string or color code representing the color that the dot drawn at the smallest value will be displayed as. Defaults to blue.
#
# :max_color - A string or color code representing the color that the dot drawn at the largest value will be displayed as. Defaults to green.
#
# :last_color - A string or color code representing the color that the dot drawn at the last value will be displayed as. Defaults to red.
def smooth
step = @options[:step].to_i
height = @options[:height].to_i
background_color = @options[:background_color]
create_canvas((@norm_data.size - 1) * step + 4, height, background_color)
min_color = @options[:min_color]
max_color = @options[:max_color]
last_color = @options[:last_color]
has_min = @options[:has_min]
has_max = @options[:has_max]
has_last = @options[:has_last]
line_color = @options[:line_color]
@draw.stroke(line_color)
coords = []
i=0
@norm_data.each do |r|
coords.push [ 2 + i, (height - 3 - r/(101.0/(height-4))) ]
i += step
end
open_ended_polyline(coords)
drawbox(coords[@norm_data.index(@norm_data.min)], 2, min_color) if has_min == true
drawbox(coords[@norm_data.index(@norm_data.max)], 2, max_color) if has_max == true
drawbox(coords[-1], 2, last_color) if has_last == true
@draw.draw(@canvas)
@canvas.to_blob
end
##
# Creates a whisker sparkline to track on/off type data. There are five states:
# on, off, no value, exceptional on, exceptional off. On values create an up
# whisker and off values create a down whisker. Exceptional values may be
# colored differently than regular values to indicate, for example, a shut out.
# No value produces an empty row to indicate a tie.
#
# * results - an array of integer values between -2 and 2. -2 is exceptional
# down, 1 is regular down, 0 is no value, 1 is up, and 2 is exceptional up.
# * options - a hash that takes parameters
#
# :height - height of the sparkline
#
# :whisker_color - the color of regular whiskers; defaults to black
#
# :exception_color - the color of exceptional whiskers; defaults to red
def whisker
# step = @options[:step].to_i
height = @options[:height].to_i
background_color = @options[:background_color]
create_canvas((@data.size - 1) * 2, height, background_color)
whisker_color = @options[:whisker_color] || 'black'
exception_color = @options[:exception_color] || 'red'
i = 0
@data.each do |r|
color = whisker_color
if ( (r == 2 || r == -2) && exception_color )
color = exception_color
end
y_mid_point = (r >= 1) ? (@canvas.rows/2.0 - 1).ceil : (@canvas.rows/2.0).floor
y_end_point = y_mid_point
if ( r > 0)
y_end_point = 0
end
if ( r < 0 )
y_end_point = @canvas.rows
end
@draw.stroke( color )
@draw.line( i, y_mid_point, i, y_end_point )
i += 2
end
@draw.draw(@canvas)
@canvas.to_blob
end
##
# Draw the error Sparkline.
def plot_error(options={})
create_canvas(40, 15, 'white')
@draw.fill('red')
@draw.line(0,0,40,15)
@draw.line(0,15,40,0)
@draw.draw(@canvas)
@canvas.to_blob
end
private
def normalize_data
@maximum_value = @data.max
if @options[:type].to_s == 'pie'
@norm_data = @data
else
@norm_data = @data.map { |value| value = (value.to_f / @maximum_value) * 100.0 }
end
end
##
# * :arr - an array of points (represented as two element arrays)
def open_ended_polyline(arr)
0.upto(arr.length - 2) { |i|
@draw.line(arr[i][0], arr[i][1], arr[i+1][0], arr[i+1][1])
}
end
##
# Create an image to draw on and a drawable to do the drawing with.
#
# TODO Refactor into smaller methods
def create_canvas(w, h, bkg_col)
@draw = Magick::Draw.new
@draw.pointsize = @@pointsize # TODO Use height
@canvas = Magick::Image.new(w , h) { self.background_color = bkg_col }
# Make room for label and last value
unless @options[:label].nil?
@options[:has_last] = true
@label_width = calculate_width(@options[:label])
@data_last_width = calculate_width(@data.last)
# HACK The 7.0 is a severe hack. Must figure out correct spacing
@label_and_data_last_width = @label_width + @data_last_width + @@label_margin * 7.0
w += @label_and_data_last_width
end
@canvas = Magick::Image.new(w , h) { self.background_color = bkg_col }
@canvas.format = "PNG"
# Draw label and last value
unless @options[:label].nil?
if ENV.has_key?('MAGICK_FONT_PATH')
vera_font_path = File.expand_path('Vera.ttf', ENV['MAGICK_FONT_PATH'])
@font = File.exists?(vera_font_path) ? vera_font_path : nil
else
@font = nil
end
@draw.fill = 'black'
@draw.font = @font if @font
@draw.gravity = Magick::WestGravity
@draw.annotate( @canvas,
@label_width, 1.0,
w - @label_and_data_last_width + @@label_margin, h - calculate_caps_height/2.0,
@options[:label])
@draw.fill = 'red'
@draw.annotate( @canvas,
@data_last_width, 1.0,
w - @data_last_width - @@label_margin * 2.0, h - calculate_caps_height/2.0,
@data.last.to_s)
end
end
##
# Utility to draw a coloured box
# Centred on pt, offset off in each direction, fill color is col
def drawbox(pt, offset, color)
@draw.stroke 'transparent'
@draw.fill(color)
@draw.rectangle(pt[0]-offset, pt[1]-offset, pt[0]+offset, pt[1]+offset)
end
def calculate_width(text)
@draw.get_type_metrics(@canvas, text.to_s).width
end
def calculate_caps_height
@draw.get_type_metrics(@canvas, 'X').height
end
end