How do you add up data in a for loop to plot in a histogram?

n=100;
[Zf_S, Zf_L] = cellfun(@(B) bounds(B, 'all'), Zf);
Zf_max = max(Zf_L);
Zf_min = min(Zf_S);
Zf_vals = linspace(Zf_min, Zf_max, n);
[Df_S, Df_L] = cellfun(@(B) bounds(B, 'all'), Df);
Df_max = max(Df_L);
Df_min = min(Df_S);
Df_vals = linspace(Df_min, Df_max, n);
for i=1:1
    ZZ = Zf{i};
    DD = Df{i};
    
    Zfr = discretize(ZZ, Zf_vals);
    Dfr = discretize(DD, Df_vals);
    zm = accumarray([Dfr Zfr], 1, [n n]);
    zmf{i}=zm;
end
 surf(Zf_vals, Df_vals, zmf);

This yields the error

Error using surf (line 71)

Z must be a matrix, not a scalar or vector.

Error in Analyze (line 236)

surf(Zf_vals, Df_vals, zmf);

What is the best way to add up all the zms so that I can plot all of the data in one histogram plot?

Answer 1

[Walter Roberson]

sum_zm = sum(cat(3, zfm{:}),3);
surf(Zf_vals, Df_vals, sum_zm, 'edgecolor', 'none');

This is not the best way: the best way is just to keep a running total without recording it in a cell array.