Nyaplot Tutorial 3: Picking colors suitable for your plots¶

Introduction¶

Nyaplot has an interface to various prepared colorsets. All of those colorsets are provided by Colorbrewer that is licensed under Apache License Version 2.0.

In [1]:

require 'nyaplot'

Out[1]:

true

Use Nyaplot::Colors#lists to show the lists of prepared colorsets.

In [3]:

Nyaplot::Colors.lists

Out[3]:

["Spectral", "RdYlGn", "RdBu", "PiYG", "PRGn", "RdYlBu", "BrBG", "RdGy", "PuOr", "Set2", "Accent", "Set1", "Set3", "Dark2", "Paired", "Pastel2", "Pastel1", "OrRd", "PuBu", "BuPu", "Oranges", "BuGn", "YlOrBr", "YlGn", "Reds", "RdPu", "Greens", "YlGnBu", "Purples", "GnBu", "Greys", "YlOrRd", "PuRd", "Blues", "PuBuGn"]

Try some of those colorsets.

In [35]:

Nyaplot::Colors.Pastel2

Out[35]:

rgb(179,226,205)	rgb(253,205,172)	rgb(203,213,232)	rgb(244,202,228)	rgb(230,245,201)	rgb(255,242,174)	rgb(241,226,204)	rgb(204,204,204)

In [17]:

Nyaplot::Colors.jet

Out[17]:

rgb(215,48,39)	rgb(244,109,67)	rgb(253,174,97)	rgb(254,224,144)	rgb(255,255,191)	rgb(224,243,248)	rgb(171,217,233)	rgb(116,173,209)	rgb(69,117,180)

In [29]:

Nyaplot::Colors.GnBu

Out[29]:

rgb(247,252,240)	rgb(224,243,219)	rgb(204,235,197)	rgb(168,221,181)	rgb(123,204,196)	rgb(78,179,211)	rgb(43,140,190)	rgb(8,104,172)	rgb(8,64,129)

In [27]:

Nyaplot::Colors.binary

Out[27]:

rgb(255,255,255)	rgb(240,240,240)	rgb(217,217,217)	rgb(189,189,189)	rgb(150,150,150)	rgb(115,115,115)	rgb(82,82,82)	rgb(37,37,37)	rgb(0,0,0)

Nyaplot::Colors#seq return random colors that is suitable for sequential data. Similarly, Nyaplot::Colors#div returns colors for diverging data, and Nyaplot::Colors#qual is for qualitative data.

In [4]:

Nyaplot::Colors.seq

Out[4]:

rgb(255,245,235)	rgb(254,230,206)	rgb(253,208,162)	rgb(253,174,107)	rgb(253,141,60)	rgb(241,105,19)	rgb(217,72,1)	rgb(166,54,3)	rgb(127,39,4)

In [19]:

Nyaplot::Colors.div

Out[19]:

rgb(213,62,79)	rgb(244,109,67)	rgb(253,174,97)	rgb(254,224,139)	rgb(255,255,191)	rgb(230,245,152)	rgb(171,221,164)	rgb(102,194,165)	rgb(50,136,189)

In [22]:

Nyaplot::Colors.qual

Out[22]:

rgb(166,206,227)	rgb(31,120,180)	rgb(178,223,138)	rgb(51,160,44)	rgb(251,154,153)	rgb(227,26,28)	rgb(253,191,111)	rgb(255,127,0)	rgb(202,178,214)

Those methods can have one argument to specify required number of colors.

In [6]:

Nyaplot::Colors.seq(3)

Out[6]:

rgb(224,243,219)	rgb(168,221,181)	rgb(67,162,202)

In [21]:

Nyaplot::Colors.Spectral(11)

Out[21]:

rgb(158,1,66)	rgb(213,62,79)	rgb(244,109,67)	rgb(253,174,97)	rgb(254,224,139)	rgb(255,255,191)	rgb(230,245,152)	rgb(171,221,164)	rgb(102,194,165)	rgb(50,136,189)	rgb(94,79,162)

Use Nyaplot::Color to try your favorite color (Credits: fatalflaws)

In [45]:

Nyaplot::Color.new(["#DEDEDE", "#ACACAC", "#1F141C", "#4A173D", "#8C547E"])

Out[45]:

#DEDEDE	#ACACAC	#1F141C	#4A173D	#8C547E

Examples¶

Then try those colors in some plots.

In [9]:

plot = Nyaplot::Plot.new
bar = plot.add(:bar, ['Persian', 'Maine Coon', 'American Shorthair'], [10,20,30])
plot.show

Out[9]:

In [25]:

colors = Nyaplot::Colors.qual(3)

Out[25]:

rgb(179,226,205)	rgb(253,205,172)	rgb(203,213,232)

In [26]:

bar.color(colors)
plot.show

Out[26]:

In [43]:

x=[]; y=[]; fill=[]
-5.step(5, 1) do |i|
  -5.step(5, 1) do |j|
    x.push(i)
    y.push(j)
    val = Math.sin(Math.sqrt(i*i+j*j))/Math.sqrt(i*i+j*j)
    fill.push((val.nan? ? 0 : val))
  end
end

plot2 = Nyaplot::Plot.new
hm = plot2.add(:heatmap, x, y, fill)
hm.width(1)
hm.height(1)
plot2.legend(true)
plot2.show

Out[43]:

In [39]:

colors = Nyaplot::Colors.GnBu

Out[39]:

rgb(247,252,240)	rgb(224,243,219)	rgb(204,235,197)	rgb(168,221,181)	rgb(123,204,196)	rgb(78,179,211)	rgb(43,140,190)	rgb(8,104,172)	rgb(8,64,129)

In [41]:

hm.color(colors)
plot2.show

Out[41]: