how to exclude a row based on a column value?

Dear All, I have a matrix called M, composed of 15 columns and 100000 rows, the third column supposed to be the month so the values in it must be from 1 to 12, how can i check if there is a value out of this range in this column, for example 13 or 0 or any thing not between 1 and 12? and after that delete the row that carries this error number?

Answer 1

[Star Strider]

Try this:

M_edited = M((M(:,3)>=1) & (M(:,3)<=12), :);

It assigns only the rows in ‘M’ with months from 1 to 12 in ‘M_edited’. The others are not copied to it.

[Roger Stafford]

@Mahmoud: Or if you fear some of the values are fractional, insert one more test:

M_edited = M((M(:,3)>=1) & (M(:,3)<=12) & (round(M(:,3))==M(:,3)), :);

[Star Strider]

@Roger — Good point! I assumed they are defined as integers. If they are calculated, rounding them or using a tolerance value will be necessary.

[MAHMOUD ALZIOUD]

thank you very much fr you help, this is amazing

[Star Strider]

My pleasure.

Thank you for describing it as ‘amazing’, and please Accept it!

[MAHMOUD ALZIOUD]

tell me please how to accept it

[Star Strider]

Click on the blue Accept this answer button.

You may have to Unaccept another answer first. (The person will not lose points for an unaccepted answer. Points of an accepted answer are permanent, even if it is unaccepted later.)

[MAHMOUD ALZIOUD]

I DID IT, THANKS

[Star Strider]

As always, my pleasure!

Thank you!