Gouldian colormap

doc/latex/pgfplots/ChangeLog

@@ -1,3 +1,7 @@
+2022-01-04 Stefan Pinnow <[email protected]>
+
+	add gouldian colormap
+
 2021-12-27 Christian Feuersaenger <[email protected]>
 
 	fix linux file read permissions of some new lua files in TDS zip
@@ -6,7 +10,7 @@
 
 	Skip non-finite values in Linear Regressions
 
-2021-07-01 Seeralan Sarvaharman <[email protected]>  
+2021-07-01 Seeralan Sarvaharman <[email protected]>
 
 	add plasma colormap
 
@@ -22,16 +26,16 @@
 		specific use-case around 'fill between' combined with 'soft clip'
 
 2021-05-08 Christian Feuersaenger <[email protected]>
-	
+
 	- RELEASED VERSION 1.18
 
-2021-04-03 Felix Kastner <[email protected]> 
+2021-04-03 Felix Kastner <[email protected]>
 
 	- fixed bug #390: image plots in log mode failed to work. Also fixed
 	issues with mesh/ordering=y varies
 
 2021-04-03 Jason Gross <[email protected]>
-	
+
 	- new feature: ignore empty coordinates when computing regression lines
 	- new feature: improve log-regression fitting of exponential functions (using variance format=linear)
 
@@ -44,7 +48,7 @@
 	- new feature: 'contour lua', implemented and contributed by Francesco Poli
 
 2019-02-29 Christian Feuersaenger <[email protected]>
-	
+
 	- RELEASED VERSION 1.17
 
 2019-02-21 Christian Feuersaenger <[email protected]>
@@ -76,20 +80,20 @@
 	- fixed bug #153: BB was scaled twice if \begin{tikzpicture}[scale=XX] and 'cell picture=false' was in effect
 
 2017-11-14 Christian Feuersaenger <[email protected]>
-	
-	- fixed bug #139 [fillbetween] numerical issues with dense points 
+
+	- fixed bug #139 [fillbetween] numerical issues with dense points
 
 2017-11-12 Christian Feuersaenger <[email protected]>
 
 	- new feature: 'x filter/.append expression', a stackable variant of 'x filter/.expression'
 
 2017-11-11 Christian Feuersaenger <[email protected]>
-	
+
 	- fixed bug: 114 fillbetween suffered from inaccuracy (produced invisible segments)
 
 2017-11-10 Christian Feuersaenger <[email protected]>
 
-	- fixed bug: #109 `visualization depends on` doesn't work with table from pgfplotstable 
+	- fixed bug: #109 `visualization depends on` doesn't work with table from pgfplotstable
 	- fixed bug: \pgfplotstablenew was unable to create tables with 0 or 1 rows.
 
 2017-11-03 Christian Feuersaenger <[email protected]>
@@ -106,37 +110,37 @@
 	- fixed #183: Nan in the first line of a numeric table was interpreted as column name
 
 2017-08-12 Christian Feuersaenger <[email protected]>
-	
+
 	- fixed #111 [fillbetween] strange behavior when `soft clip` is used and one of the paths touches the axis border
 
 2017-06-05 Christian Feuersaenger <[email protected]>
 
 	- RELEASED VERSION 1.15
 
 2017-06-05 Christian Feuersaenger <[email protected]>
-	- fixed bug 176: 2d plot expression in 3d axis fails for lualatex 
+	- fixed bug 176: 2d plot expression in 3d axis fails for lualatex
 
 2017-06-03 Christian Feuersaenger <[email protected]>
-	
+
 	- improved precision of |.define layer set| (todo remark of Stefan)
 
 2017-04-29 Christian Feuersaenger <[email protected]>
-	
-	- fixed bug 163 [bar-chart] bars dissapear when values are >xmax/ymax 
+
+	- fixed bug 163 [bar-chart] bars dissapear when values are >xmax/ymax
 	- fixed bug 81 cannot use dollar sign as 'comment char'
-	- fixed bug 91 Hashes in data 
+	- fixed bug 91 Hashes in data
 	- fixed bug 165 [minor ticks] minor tick drawn after the last xtick
 
 2017-03-18 Christian Feuersaenger <[email protected]>
 
-	- fixed bug 150 Usage of \pgfkeysvalueof in xtick leads to 'Dimension too large' 
+	- fixed bug 150 Usage of \pgfkeysvalueof in xtick leads to 'Dimension too large'
 	- fixed bug 105 [manual] `xticklabel pos=upper` is not documented
 	    in fact, some of the documented positions for 'xtick pos' where
 		unavailable.
-	- fixed bug 155 [groupplots] `scaled ticks` does not recognize `ticklabels at` 
-	- fixed bug 160 `xticklabels` also used for `extra x tick labels` if they are not given explicitely 
-	- implemented partial solution for bug 154 [log mode] sampling in 2D and 3D different 
-	
+	- fixed bug 155 [groupplots] `scaled ticks` does not recognize `ticklabels at`
+	- fixed bug 160 `xticklabels` also used for `extra x tick labels` if they are not given explicitely
+	- implemented partial solution for bug 154 [log mode] sampling in 2D and 3D different
+
 2017-02-11 Christian Feuersaenger <[email protected]>
 
 	- fixed bug 140 (pgfplotstable read does not process empty rows anymore)
@@ -150,8 +154,8 @@
 	- added support for \plotnum during \addplot
 
 2017-01-19 Christian Feuersaenger <[email protected]>
-	
-	- fixed bug #149 : \edef{...\to...} was wrong and caused \pgfplotstablevertcat to fail 
+
+	- fixed bug #149 : \edef{...\to...} was wrong and caused \pgfplotstablevertcat to fail
 
 2016-09-17 Christian Feuersaenger <[email protected]>
 
@@ -3260,7 +3264,6 @@ y	- Provided first rudimentary version for \pgfplotstablesort
 	Gain: about 12% faster than before!
 	- added |use aftergroup stack as fast list| to allow O(N) time for large scale plot
 	commands, given appropriate safe stack parameters of TeX.
-
 
 2008-07-15 Christian Feuersaenger <[email protected]>
 

doc/latex/pgfplots/pgfplots.libs.colormaps.tex

@@ -1,5 +1,6 @@
 
 \section{Colormaps}
+\label{sec:colormaps}
 \begingroup
 \def\pgfplotsmanualcurlibrary{colormaps}
 
@@ -335,5 +336,30 @@ \section{Colormaps}
     \pgfplotsshowcolormap{plasma high res}
 \end{stylekey}
 
+\begin{stylekey}{/pgfplots/colormap/gouldian high res}
+    A style with installs the colormap ``gouldian'' (CET-L20) which has been
+    designed by Peter Kovesi and is similar to the Parula colormap in
+    Matlab$^\text{\textregistered}$. It is released under the
+    \href{http://creativecommons.org/licenses/by/4.0/legalcode}{Creative Commons
+    BY License}.
+
+    Please refer to \url{https://colorcet.com/userguide/#gouldianparula} and
+    \url{https://colorcet.com/download/index.html} for details.
+    %
+\begin{codeexample}[code only]
+\pgfplotsset{
+    colormap name=gouldian,
+}
+\end{codeexample}
+    \pgfplotsshowcolormap{gouldian}
+
+\begin{codeexample}[code only]
+\pgfplotsset{
+    colormap/gouldian high res,
+}
+\end{codeexample}
+    \pgfplotsshowcolormap{gouldian high res}
+\end{stylekey}
+
 \end{pgfplotslibrary}
 \endgroup

doc/latex/pgfplots/pgfplots.reference.axisdescription.tex

@@ -1668,8 +1668,12 @@ \subsection{Legend Appearance}
     %
 \pgfplotsexpensiveexample
 \begin{codeexample}[]
+% requires \usepgfplotslibrary{colormaps}
 \begin{tikzpicture}
-    \begin{axis}[legend pos=outer north east]
+    \begin{axis}[
+        colormap/gouldian,
+        legend pos=outer north east,
+    ]
         \addplot3 [surf,samples=9,domain=0:1]
             {(1-abs(2*(x-0.5))) * (1-abs(2*(y-0.5)))};
         \addlegendentry{$\phi_x \phi_y$}
@@ -2845,8 +2849,12 @@ \subsection{Color Bars}
 \end{codeexample}
 
 \begin{codeexample}[]
+% requires \usepgfplotslibrary{colormaps}
 \begin{tikzpicture}
-\begin{axis}[colorbar horizontal]
+\begin{axis}[
+    colormap/gouldian,
+    colorbar horizontal,
+]
     \addplot [mesh,ultra thick] {x};
 \end{axis}
 \end{tikzpicture}
@@ -2967,7 +2975,10 @@ \subsection{Color Bars}
     %
 \begin{codeexample}[]
 \begin{tikzpicture}
-    \begin{axis}[colorbar left]
+    \begin{axis}[
+        colormap/viridis,
+        colorbar left,
+    ]
         \addplot [mesh,thick,samples=150]
             {x*sin(deg(4*x))};
     \end{axis}
@@ -3002,8 +3013,12 @@ \subsection{Color Bars}
     color bars are placed below their parent axis, with a horizontal bar.
     %
 \begin{codeexample}[]
+% requires \usepgfplotslibrary{colormaps}
 \begin{tikzpicture}
-\begin{axis}[colorbar horizontal]
+\begin{axis}[
+    colormap/gouldian,
+    colorbar horizontal,
+]
     \addplot [
         only marks,
         scatter,

doc/latex/pgfplots/pgfplots.tutorial4.tex

@@ -116,10 +116,12 @@ \subsection{Fine-Tuning}
 %
 \pgfplotsexpensiveexample
 \begin{codeexample}[]
+% requires \usepgfplotslibrary{colormaps}
 \begin{tikzpicture}
 \begin{axis}[
     view/h=40,
     colorbar horizontal,
+    colormap/gouldian,
     xlabel=$x$, ylabel=$y$,
 ]
     \addplot3 [
@@ -136,10 +138,12 @@ \subsection{Fine-Tuning}
 a |view/v| key and a |view=|\marg{h}\marg{v} variant.
 
 The key |colorbar horizontal| is a style which activates a |colorbar| and
-configures it to be displayed horizontally. The labels are placed using
-|xlabel| and |ylabel| as we saw it before for visualizations of one-dimensional
-functions. A colorbar uses the current |colormap| and adds axis descriptions to
-show how values are mapped to colors.
+configures it to be displayed horizontally. |colormap/gouldian| loads and sets
+a better color map (for which we need to load the |colormaps| library; see
+Section~\ref{sec:colormaps}). The labels are placed using |xlabel| and |ylabel|
+as we saw it before for visualizations of one-dimensional functions. A colorbar
+uses the current |colormap| and adds axis descriptions to show how values are
+mapped to colors.
 
  The |shader=interp| key activates a smooth color interpolation.
 
@@ -158,10 +162,12 @@ \subsection{Adding Scattered Data on Top of the Surface}
 %
 \pgfplotsexpensiveexample
 \begin{codeexample}[]
+% requires \usepgfplotslibrary{colormaps}
 \begin{tikzpicture}
 \begin{axis}[
     view/h=40,
     colorbar horizontal,
+    colormap/gouldian,
     xlabel=$x$, ylabel=$y$,
 ]
     \addplot3 [surf,mesh/ordering=y varies,
@@ -329,10 +335,10 @@ \subsection{Computing a Contour Plot of a Math Expression}
 
 |pdflatex |\meta{texfilename} .
 
-\noindent 
+\noindent
 The nonlinear algorithm to
 compute contour lines is currently unavailable in plain \TeX{} which is stressed
-by the name `|contour lua|'. 
+by the name `|contour lua|'.
 
 
 If you cannot use |lualatex| for some reason, you can replace |contour lua| by |contour gnuplot|, provided that you have the external program |gnuplot| installed on your system (see the reference for |contour gnuplot| for more details).