# How to use colormap for different bars.

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ref on 10 Nov 2011
I am trying to plot a bar chart with error bars, giving different colors to the individual bars using colormap function, but instead I get the same color for all bars. How can i set the bars following one specific colormap?
y = [4.2; 4.6; 5]; %The data.
s = [.3; .2; .6]; %The standard deviation.
h = bar(y);
colormap(hsv(h))
hold on
set(gca, ...
'XTickLabelMode', 'manual', ...
'XTickLabel', {'R0', 'R1', 'R2'})
h1 = errorbar(y,s,'r');
set(h1,'linestyle','none')

Jonathan on 11 Nov 2011
See if this helps.
y = [4.2; 4.6; 5]; %The data.
s = [.3; .2; .6]; %The standard deviation.
fHand = figure;
aHand = axes('parent', fHand);
hold(aHand, 'on')
colors = hsv(numel(y));
for i = 1:numel(y)
bar(i, y(i), 'parent', aHand, 'facecolor', colors(i,:));
end
set(gca, 'XTick', 1:numel(y), 'XTickLabel', {'R0', 'R1', 'R2'})
errorbar(y,s,'r');

#### 1 Comment

ref on 11 Nov 2011
Thank you, exactly what i was looking for.

ref on 11 Nov 2011
Sorry, I have one more question. When "y" has 3 elements, then the colors I get for the bars are "red, green & blue". When I change the elements of "y" to 4, or 5, Matlab does not give the same colors. Instead it gives "red, light green, light blue and purple". Is it possible to hold constant the colors for the elements? I need the same color for the first-second-third element independently the number of elements of "y".

Jonathan on 11 Nov 2011
You can try something like this modification.
bar(1, y(1), 'parent', aHand, 'facecolor', 'r');
bar(2, y(2), 'parent', aHand, 'facecolor', 'g');
bar(3, y(3), 'parent', aHand, 'facecolor', 'b');
colors = copper(numel(y) - 3);
for i = 4:numel(y)
bar(i, y(i), 'parent', aHand, 'facecolor', colors(i-3,:));
end
ref on 11 Nov 2011
Thx a lot Jonathan.