Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: matrix function that compare a list of real numbers with a real number
Replies: 3   Last Post: Nov 20, 2012 10:52 AM

 Messages: [ Previous | Next ]
 Jos Posts: 1,268 Registered: 10/24/08
Re: matrix function that compare a list of real numbers with a real number
Posted: Nov 20, 2012 4:09 AM

"felix " <f_3lix@hotmail.com> wrote in message <k8d4le\$dmc\$1@newscl01ah.mathworks.com>...
> I need a function which accepts as input a list of real numbers, and a real number X and which returns to the output:
> ? The number of how many times the number (X) appear in the table
> ? The location where this number appears in the table
> ? A table that will have the value 0 in the positions where (X) appears and the value -1 in the remaining positions
> ? A table(matrix) where the elements of the original matrix that is larger than the input number (X) will be replaced with the maximum number of the original table
> ? A vector which will contain all the unique elements of the input table which are larger than the number(X) we gave to the entrance.

take a look at logical indexing.

tf = T = X
sum(tf)
find(tf)
Y(~tf) = -1
etc.

~ Jos

Date Subject Author
11/19/12 felix
11/19/12 felix
11/20/12 Jos
11/20/12 Curious