MATLAB: Optimizing nested for loop

for looploopoptimizationspeed

I have the following for loop and it take quite a while to complete when I am sure it can be faster. It looks up an input value from the assigned dataset and extracts parameters from the struct based on the bin it falls into. Once these parameters have been selected for, the output is based on a calculation.
nrows = length(inpdata);
ncols = 2:2:12;
for j = ncols;
    for i = 1:nrows;
        if j == 2
            height = 'height10m';
        elseif j == 4
            height = 'height20m';
        elseif j == 6
            height = 'height40m';
        elseif j == 8
            height = 'height80m';
        elseif j == 10
            height = 'height120m';            
        elseif j == 12
            height = 'height200m';        
        end
          if inpdata(i,j) > 0
              param = strcat('params',num2str(length(bin(bin < inpdata(i,j)))));
              gusts(i,j) = inpdata(i,j) + (inpdata2.(height).(param)(1,3)*(inpdata(i,j)^(1 + inpdata2.(height).(param)(1,1)))); 
          elseif inpdata(i,2) == 0
              param = 'params1';
              gusts(i,j) = inpdata(i,j) + (inpdata2.(height).(param)(1,3)*(inpdata(i,j)^(1 + inpdata2.(height).(param)(1,1)))); 
          end
      end
  end
I am not too sure how to optimize this for more efficiency but does anyone have any suggestions? The profiler shows that it is the strcat and num2str functions that are the main culprits but I am not sure how to optimize them as I need them in the loop.

Best Answer

If that's the significant fraction, you can try
param=sprintf('params%d',length(bin(bin < inpdata)));
instead.
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