How to delete the row that contains specific numbers on the cells

Hi, I have a matrix of 80x2, each cell contains certain values. My aim is to delete the rows in which both cells in the rows contain the values "-99.9". An example of the first 3 rows is as attached.

Answer 1

[Walter Roberson]

If you have R2015a or later, and if your values are all numeric and the same size, then

   to_delete_mask = ismembertol(cell2mat(YourCell), [-99.9, -99.9], 'ByRows', true);
   YourCell(to_delete_mask,:) = [];

If you are using an earlier release you will need to test abs() of the difference to -99.9 against a small tolerance.

It may appear that you should be able to just compare your values to -99.9 but you cannot do so because of floating point precision roundoff; what looks like exactly -99.9 is not exactly that because it is not possible to exactly represent the fraction 9/10 in finite binary floating point.

[Samantha Chong]

Hi, thanks for your reply :)

I'm currently using R2011a and I've tested with ismembertol but it can't recognize the function. So, I guess I should go for the second option which you've suggested. However, I don't really understand the 2nd option. It would be great if you could show me the related codes :)

Cheers

[Walter Roberson]

tolerance = 1e-12;
to_delete_mask = all( abs(cell2mat(YourCell) - (-99.9)) < tolerence, 2);
YourCell(to_delete_mask,:) = [];