HELP WITH 3-D SURF PLOT !!!!

I want to plot Date and time against the power production, every variable has the lenght of 13104.

But if i want to plot this error come up :

 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Error using reshape
To RESHAPE the number of elements must not change.

Error in Bachelorarbeit (line 173)
    z=reshape(POutput,length(y),length(x)); 
%%%%%%%%%%%%%%%%%%%%%%

ttab=table(Date1,t,POutput); % compare everything has the same length
 
    % creating the parameter
    x=unique(Date1); %returns the data, but without repetition
    y=unique(t); %returns the data, but without repetition
    z=reshape(POutput,length(y),length(x)); 
    %creating the matrix z length(x)
    %returns the length of the largest array dimension in x and y
    % creating a surface plot
    surf(x,y,z,'Facecolor','interp') %create a surface plot
    colorbar % add a colorbar
    colormap(jet) % adjust the colorrange from the surface plot
    zlabel('Leistung in MW') %label the z-axis
    %print('Usage','-dpng') % if you want to save the plot

Answer 1

[Stephan]

Hi Felix,

i hope the work on your thesis runs well. As the error message says the number of elements in a reshaped matrix is not allowed to change:

>> A = randi(3,1,6)

A =

     3     2     2     1     3     1

>> B =reshape(A,2,[])

B =

     3     2     3
     2     1     1

my example shows that you can leave away one dimension - reshape claculates the needed number of columns in this case. The following will produce error, because there are only 6 elements in A instead of 8:

     >> B =reshape(A,2,4)
Error using reshape
To RESHAPE the number of elements must not change.

The command above would cause a 2x4 matrix but A has only 6 - so the result is an error. Check your code in terms of this problem. To make it more precise it seems that the prodct of

length(y) * length(x)

is not equal to:

numel(POutput)

which causes this error.

Best regards & always good weather ;-)

Stephan