@@ -109,14 +109,15 @@ These would not be good options for use as perceptual colormaps.
109109Miscellaneous
110110-------------
111111
112- Some of the miscellaneous colormaps have particular uses they have been created
113- for. For example, gist_earth, ocean, and terrain all seem to be created for
114- plotting topography (green/brown) and water depths (blue) together. We would
115- expect to see a divergence in these colormaps, then, but multiple kinks may not
116- be ideal, such as in gist_earth and terrain. CMRmap was created to convert well
117- to grayscale, though it does appear to have some small kinks in :math: `L^*`.
118- cubehelix was created to vary smoothly in both lightness and hue, but appears to
119- have a small hump in the green hue area.
112+ Some of the miscellaneous colormaps have particular uses for which
113+ they have been created. For example, gist_earth, ocean, and terrain
114+ all seem to be created for plotting topography (green/brown) and water
115+ depths (blue) together. We would expect to see a divergence in these
116+ colormaps, then, but multiple kinks may not be ideal, such as in
117+ gist_earth and terrain. CMRmap was created to convert well to
118+ grayscale, though it does appear to have some small kinks in
119+ :math: `L^*`. cubehelix was created to vary smoothly in both lightness
120+ and hue, but appears to have a small hump in the green hue area.
120121
121122The often-used jet colormap is included in this set of colormaps. We can see
122123that the :math: `L^*` values vary widely throughout the colormap, making it a
@@ -141,17 +142,18 @@ might be better (see effort on this front at [mycarta-cubelaw]_).
141142Grayscale conversion
142143====================
143144
144- Conversion to grayscale is important to pay attention to for printing
145- publications that have color plots. If this is not paid attention to ahead of
146- time, your readers may end up with indecipherable plots because the grayscale
147- changes unpredictably through the colormap.
145+ It is important to pay attention to conversion to grayscale for color
146+ plots, since they may be printed on black and white printers. If not
147+ carefully considered, your readers may end up with indecipherable
148+ plots because the grayscale changes unpredictably through the
149+ colormap.
148150
149151Conversion to grayscale is done in many different ways [bw ]_. Some of the better
150152ones use a linear combination of the rgb values of a pixel, but weighted
151153according to how we perceive color intensity. A nonlinear method of conversion
152154to grayscale is to use the :math: `L^*` values of the pixels. In general, similar
153155principles apply for this question as they do for presenting one's information
154- perceptually; that is, if a colormap is chosen that has monotonically increasing
156+ perceptually; that is, if a colormap is chosen that is monotonically increasing
155157in :math: `L^*` values, it will print in a reasonable manner to grayscale.
156158
157159With this in mind, we see that the Sequential colormaps have reasonable
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