Undefined operator / for input arguements of type cell.

I realize this question may have been asked a billion times, but I can't for the life of me see why its popping up with my code. I'm calculating the maximum value in a data set 'bridge1Load' through this loop:

maxLoad1 = 0;
for n = 1:length(bridge1Load)
  for k = 1
    if bridge1Load(n, k) > maxLoad1
      maxLoad1 = bridge1Load(n, k);
    end
  end
end

and my bridge weight is a user input from:

bridge1WeightInput = inputdlg('Please enter the weight of bridge #1','Bridge #1 Weight');

I'm trying to calculate the strength to weight ratio via:

s2wRatio1 = maxLoad1 / bridge1Weight;

but I keep getting the error stated above.

[Anas Abou Allaban]

Note that I used str2num and it still didnt work:

bridge1Weight = str2num(bridge1WeightInput);

[dpb]

bridge1Load must be a cell array, not a double, then. A likely candidate to have caused that would be reading the data from a file via textscan.

The best solution relies somewhat on just what the form of the data are; how was it actually loaded/obtained and specifically, what does

whos bridge1Load

return?

Then we can look at "more better" ways to do the above as well...

Answer 1

[Anas Abou Allaban]

Please ignore this rather silly question, I had to use str2double.....

[dpb]

OK, although I'dve thunk that'd given a message regarding cell strings, not just cell.

Anyway, as noted, "the Matlab way" for the above once you have the 2D array (matrix) is

maxload1=max(bridge1Load(:);

no loops needed. The {:} returns the array as a vector, hence the maximum will be found over all elements in the array, otherwise, max operates by column so one often sees such code as

maxload1=max(max(bridge1Load));

to do the same thing. (Try a small array of random values at the command line to see how it works).

You're not keeping track of the location at which the max occurs above; one would presume that also will be of some interest before you're done completely. For that, use the optional index returned by max and convert to the row/column position in the array via ind2sub

[maxload1,imx]=max(max(bridge1Load));
[rmax,cmax]=ind2sub(size(bridge1Load),imx);