How can I color bars to correspond to their heights when using BAR3?

Each column in a BAR or BAR3 plot is symbolized in a single color irrespective of the height of the bar itself. I would like MATLAB to color each bar with a color proportional to its height above the base plane.

Answer 1

[MathWorks Support Team]

The ability to color the bars to correspond to their heights is not available in MATLAB. The following pieces of code provide some useful workarounds:

Z = rand(5,5);

h = bar3(Z);

for i = 1:length(h)

     zdata = get(h(i),'Zdata');

     set(h(i),'Cdata',zdata)

end

An alternate workaround where the bars are shaded:

figure

h = bar3(Z);

shading interp

for i = 1:length(h)

     zdata = get(h(i),'Zdata');

     set(h(i),'Cdata',zdata)

     set(h,'EdgeColor','k')

end

An alternate workaround where the bars can have solid colors uses this code:

Z = rand(8,3);

h = bar3(Z);

numBars = size(Z,1);

numSets = size(Z,2);

for i = 1:numSets

    zdata = ones(6*numBars,4);

    k = 1;

    for j = 0:6:(6*numBars-6)

      zdata(j+1:j+6,:) = Z(k,i);

      k = k+1;

    end

    set(h(i),'Cdata',zdata)

end

Note that none of the above code fragments work with the BAR function, which creates barseries objects having somewhat different properties than the patch objects used by BAR3.

[Jan]

Please remove the empty lines between the lines of code to improve the readability.

If the input data is a vector, the bars have all the same color. This occurs in R2011b (HG1) and R2015b (HG2).