BLUEWHITERED(M) returns an M-by-3 matrix containing a blue to white to red colormap, with white corresponding to the CAXIS value closest to zero. This colormap is most useful for images and surface plots with positive and negative values. BLUEWHITERED, by itself, is the same length as the current colormap.

Examples:
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figure
imagesc(peaks(250));
colormap(bluewhitered(256)), colorbar

figure
imagesc(peaks(250), [0 8])
colormap(bluewhitered), colorbar

figure
imagesc(peaks(250), [-6 0])
colormap(bluewhitered), colorbar

figure
surf(peaks)
colormap(bluewhitered)
axis tight