MATLAB: Replace all values of cells between two positions

MATLABmatrix manipulation

I have a matrix and vectors of noise onsets and correspondig offsets positions for each row in the matrix.
I need to replace all the cell values between onsets and offsets with NaN's. For example:
matrix =
29.6676 48.8609 67.9136 33.5357 89.0923 61.7666 97.8681 81.8149 43.2392 52.6876
31.8778 57.8525 39.5515 67.9728 33.4163 85.9442 71.2694 81.7547 82.5314 41.6799
42.4167 23.7284 36.7437 13.6553 69.8746 80.5489 50.0472 72.2440 8.3470 65.6860
50.7858 45.8849 98.7982 72.1227 19.7810 57.6722 47.1088 14.9865 13.3171 62.7973
onsets_row1 = [1 5]
offsets_row1 = [3 8]
new_matrix =
NaN NaN NaN 33.5357 NaN NaN NaN NaN 43.2392 52.6876
31.8778 57.8525 39.5515 67.9728 33.4163 85.9442 71.2694 81.7547 82.5314 41.6799
42.4167 23.7284 36.7437 13.6553 69.8746 80.5489 50.0472 72.2440 8.3470 65.6860
50.7858 45.8849 98.7982 72.1227 19.7810 57.6722 47.1088 14.9865 13.3171 62.7973
How do I replace all the values between onsets and offsets?
thnx

Best Answer

For an aribtrary number of rows and an aribitrary number of indices using loops is about the most straightforward way of doing this, e.g.
M = [
  29.668  48.861  67.914  33.536  89.092  61.767  97.868  81.815  43.239  52.688
  31.878  57.853  39.552  67.973  33.416  85.944  71.269  81.755  82.531  41.680
  42.417  23.728  36.744  13.655  69.875  80.550  50.047  72.244   8.347  65.686
  50.786  45.885  98.798  72.123  19.781  57.672  47.109  14.987  13.317  62.797
];
X = {[1,5],[3,8];[2,6,8],[4,6,10]}; % {begR1,endR1;begR2,endR2;...;begRn,endRn}
for r = 1:size(X,1)
    for c = 1:numel(X{r,1})
        M(r,X{r,1}(c):X{r,2}(c)) = NaN;
    end
end
disp(M)
Giving:
 M =
     NaN     NaN     NaN  33.536     NaN     NaN     NaN     NaN  43.239  52.688
  31.878     NaN     NaN     NaN   3.416     NaN  71.269     NaN     NaN     NaN
  42.417  23.728  36.744  13.655  69.875  80.549  50.047  72.244   8.347  65.686
  50.786  45.885  98.798  72.123  19.781  57.672  47.109  14.987  13.317  62.797
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