Which colormaps are supported?
FieldTrip includes a helper-function ft_colormap with which you can select any of the standard MATLAB colormaps, but also those of Matplotlib, Brewermap, CMOcean and ColorCET.
You can use ft_colormap just like you would the standard MATLAB colormap function. Furthermore, most plotting functions support the option cfg.colormap with which you can specify the desired colormap.
The following sections of code loop through a large number of the available colormaps.
MATLAB
cmap = {'parula', 'jet', 'hsv', 'hot', 'cool', 'spring', 'summer', 'autumn', 'winter', 'gray', 'bone', 'copper', 'pink', 'lines', 'colorcube', 'prism', 'flag'};
figure
set(gcf, 'Name', 'matlab')
for i=1:length(cmap)
subplot(length(cmap),1,i)
rgb = ft_colormap(cmap{i});
image(reshape(rgb, [1 64 3]))
axis off
text(65, 1, cmap{i})
end
Matplotlib
cmap = {'cividis', 'inferno', 'magma', 'plasma', 'tab10', 'tab20', 'tab20b', 'tab20c', 'twilight', 'viridis'};
figure
set(gcf, 'Name', 'matplotlib')
for i=1:length(cmap)
subplot(length(cmap),1,i)
rgb = ft_colormap(cmap{i});
image(reshape(rgb, [1 64 3]))
axis off
text(65, 1, cmap{i})
end
Brewermap
cmap = {'BrBG', 'PRGn', 'PiYG', 'PuOr', 'RdBu', 'RdGy', 'RdYlBu', 'RdYlGn', 'Spectral', 'Accent', 'Dark2', 'Paired', 'Pastel1', 'Pastel2', 'Set1', 'Set2', 'Set3', 'Blues', 'BuGn', 'BuPu', 'GnBu', 'Greens', 'Greys', 'OrRd', 'Oranges', 'PuBu', 'PuBuGn', 'PuRd', 'Purples', 'RdPu', 'Reds', 'YlGn', 'YlGnBu', 'YlOrBr', 'YlOrRd'};
figure
set(gcf, 'Name', 'brewermap')
for i=1:length(cmap)
subplot(length(cmap),1,i)
rgb = ft_colormap(cmap{i});
image(reshape(rgb, [1 64 3]))
axis off
text(65, 1, cmap{i})
end
CMOcean
cmap = {'thermal', 'haline', 'solar', 'ice', 'gray', 'oxy', 'deep', 'dense', 'algae', 'matter', 'turbid', 'speed', 'amp', 'tempo', 'rain', 'phase', 'topo', 'balance', 'delta', 'curl', 'diff', 'tarn'};
figure
set(gcf, 'Name', 'cmocean')
for i=1:length(cmap)
subplot(length(cmap),1,i)
rgb = ft_colormap(cmap{i});
image(reshape(rgb, [1 64 3]))
axis off
text(65, 1, cmap{i})
end
ColorCET
cmap = {'blueternary', 'coolwarm', 'cyclicgrey', 'depth', 'divbjy', 'fire', 'geographic', 'geographic2', 'gouldian', 'gray', 'greenternary', 'grey', 'heat', 'phase2', 'phase4', 'rainbow', 'rainbow2', 'rainbow3', 'rainbow4', 'redternary', 'reducedgrey', 'yellowheat'};
figure
set(gcf, 'Name', 'colorcet')
for i=1:length(cmap)
subplot(length(cmap),1,i)
rgb = ft_colormap(cmap{i});
image(reshape(rgb, [1 64 3]))
axis off
text(65, 1, cmap{i})
end
Cyclic copormaps for phase plots
To plot phase color-coded, you need a colormap that starts and ends at the same color. Some of the colormaps that can be used are hsv, phase, phase2, phase4, and cyclicgrey. You can check these yourself using the following code.
% construct linearly increasing angles that wrap twice
a = [linspace(-pi, pi) linspace(-pi, pi) linspace(-pi, pi)]
figure
plot(a)
figure
imagesc(a)
ft_colormap phase