How to deleter specific elements from a matrix without changing its shape

I have this matrix and i want to delete every number greater than 0.81 in each column but without changing the overall structure or size of the matrix. The number of columns should be the same only the values in each column should be limited

[Walter Roberson]

When you "delete" you end up with less than you had, so the result could not have the same size.

There are only 4 rows in which none of the values exceed the bounds, so in order to keep the same shape the output would have to be 4 x 20.

[Maaz Madha]

i meant the same number of columns. So deleting any value greater than 0.81 in each column( for example deleting 1.0071 onwards from the first column) and so on and so forth for each column

[Walter Roberson]

Do I understand correctly that you want to end up with 20 columns, but each column would be a different length since different number of values would be deleted from it?

If so there is no way to do that using numeric arrays. You would have to put the values into cell arrays.

Answer 1

[David Hill]

Instead of deleting why not change them to nan?

yourMatrix(yourMatrix>0.81)=nan;

[Maaz Madha]

becasue i want to use these values for further calculations and im not sure nan would work with calculations

Answer 2

[Walter Roberson]

%perhaps you meant
yourMatrix(any(yourMatrix>0.81,2),:) = [];

%but column 20 is obviously different and perhaps it should be left out
mask = any(yourMatrix(:,1:end-1)>0.81,2);
yourMatrix(mask,:) = [];