sparklines.rb in sparklines-0.2.5

- old
+ new

@@ -20,10 +20,12 @@
 {Geoffrey Grosenbach}[mailto:boss@topfunky.com] -- http://nubyonrails.topfunky.com 
 -- Conversion to module and addition of functions for using with Rails. Also changed functions to use Rails-style option hashes for parameters.
 
 ===Tangent regarding RMagick
 
+The easiest way to use RMagick on Mac OS X is to use darwinports. There are packages for libpng, freetype, and all the other libraries you need.
+
 I had a heck of a time getting RMagick to work on my system so in the interests of saving other people the trouble here's a little set of instructions on how to get RMagick working properly and with the right image formats.
 
 1. Install the zlib[http://www.libpng.org/pub/png/libpng.html] library
 2. With zlib in the same directory as the libpng[http://www.libpng.org/pub/png/libpng.html] library, install libpng
 3. Option step: Install the {jpeg library}[ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz] (You need it to use jpegs and you might want to have it)
@@ -68,10 +70,11 @@
 
  area
  discrete
  pie
  smooth
+ bar (results will be normalized, i.e. scaled to take up the full height of the graph)
 
 General Defaults:
 
  :type =>  'smooth'
  :height  =>  14px
@@ -86,11 +89,11 @@
 Licensed under the MIT license.
 
 =end
 
 module Sparklines
-	$VERSION = '0.2.3'
+	$VERSION = '0.2.5'
 
 	# Does the actually plotting of the graph. Calls the appropriate function based on the :type value passed. Defaults to 'smooth.'
 	def Sparklines.plot(results=[], options={})
 		defaults = {	:type => 'smooth',
 				:height => 14,
@@ -113,29 +116,20 @@
 				:has_last => false
 							}
 			
 		# This symbol->string->symbol is kind of awkward. Is there a more elegant way?
 			
-		# Convert all symbol keys to strings
-		defaults.keys.reverse.each do |key|
-			defaults[key.to_s] = defaults[key]
-		end
 		options.keys.reverse.each do |key|
-			options[key.to_s] = options[key]
-		end
-
-		options  = defaults.merge(options)
-
-		# Convert options string keys back to symbols
-		options.keys.reverse.each do |key|
 			options[key.to_sym] = options[key]
 		end
-
+		options  = defaults.merge(options)
 		
+		# Minimal normalization
+		maximum_value = self.get_max_value(results).to_f
+		
 		# Call the appropriate function for actual plotting
-		#self.send('smooth', results, options)
-		self.send(options[:type], results, options)
+		self.send(options[:type], results, options, maximum_value)
 	end
 
 	# Writes a graph to disk with the specified filename, or "Sparklines.png"
 	def Sparklines.plot_to_file(filename="sparklines.png", results=[], options={})
 		File.open( filename, 'wb' ) do |png|
@@ -152,11 +146,11 @@
 # :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 blue.
 #
 # :remain_color - A string or color code representing the color to draw the pie not taken by the share color. Defaults to lightgrey.
-	def self.pie(results=[],options={})
+	def self.pie(results=[],options={}, maximum_value=100.0)
 
 		diameter = options[:diameter].to_i
 		share_color = options[:share_color]
 		remain_color = options[:remain_color]
 		percent = results[0]
@@ -224,27 +218,29 @@
 # :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 self.discrete(results=[], options = {})
+	def self.discrete(results=[], options = {}, maximum_value=100.0)
 
 		height = options[:height].to_i
 		upper = options[:upper].to_i
 		below_color = options[:below_color]
 		above_color = options[:above_color]
 
 		img = Magick::Image.new(results.size * 2 - 1, height) {self.background_color = options[:background_color]}
 		img.format = "PNG"
 		draw = Magick::Draw.new
 
-		i=0
+		i = 0
 		results.each do |r|
-			color = (r >= upper) && above_color || below_color
+			color = (r >= upper) ? above_color : below_color
 			draw.stroke(color)
-			draw.line(i, (img.rows - r/(101.0/(height-4))-4).to_i,i,(img.rows - r/(101.0/(height-4))).to_i)
-			i+=2
+			draw.line(i, (img.rows - r/(101.0/(height-4))-4).to_i,
+			          i, (img.rows - r/(101.0/(height-4))).to_i)
+
+			i += 2
 		end
 
 		draw.draw(img)
 		img.to_blob
 	end
@@ -274,11 +270,11 @@
 # :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 self.area(results=[], options={})
+	def self.area(results=[], options={}, maximum_value=100.0)
 		
 		step = options[:step].to_i
 		height = options[:height].to_i
 		upper = options[:upper].to_i
 
@@ -369,11 +365,11 @@
 # :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 self.smooth(results, options)
+	def self.smooth(results, options, maximum_value=100.0)
 	
 		step = options[:step].to_i
 		height = options[:height].to_i
 		min_color = options[:min_color]
 		max_color = options[:max_color]
@@ -442,6 +438,46 @@
 		draw.draw(img)
 
 		img.to_blob
 	end
 
+
+  # Draws a bar graph, normalized.
+  #
+  # BUG: Last column never goes all the way to the bottom.
+  def self.bar(results=[], options = {}, maximum_value=100.0)
+    step = options[:step].to_i
+    height = options[:height].to_f
+    upper = options[:upper].to_i
+    below_color = options[:below_color]
+    above_color = options[:above_color]
+
+    img = Magick::Image.new((results.size) * step + 1, height) {
+            self.background_color = options[:background_color]
+          }
+    img.format = "PNG"
+    draw = Magick::Draw.new
+
+    i = 1
+    results.each_with_index do |r, index|
+      color = (r >= upper) ? above_color : below_color
+      draw.stroke('transparent')
+      draw.fill(color)
+      draw.rectangle( i, img.rows, 
+                      i + step - 2, img.rows - ((r / maximum_value) * img.rows) )      
+      i += step
+    end
+
+    draw.draw(img)
+    img.to_blob
+  end
+
+
+  def self.get_max_value(values=[])
+    max_value = 0
+    values.each do |value|
+      max_value = (value > max_value) ? value : max_value
+    end
+    return max_value
+  end
+  
 end