topic Re: Convert Matrix to List? in Discussions

Convert Matrix to List?

pmroz — Fri, 29 Oct 2010 14:47:21 GMT

Hi JMP folks,

I can do this in a loop, but is there a simple one-liner to convert a one-dimensional matrix to a list? Something like:

cell_list = getmatrixaslist(cell_matrix);

Additional bonus question: is there an equivalent to the list LOC function for a matrix? I need to locate all rows in a matrix with a certain value. The LOC function does this for lists, but for matrices it finds all elements equal to 0.

Thanks!
Peter

Re: Convert Matrix to List?

Fri, 29 Oct 2010 17:39:08 GMT

You can use the LOC function to locate all rows of a matrix that are equal to a value. Consider the following example:

If my matrix is

m=[1,3,3,6,7,1,3,9]

then use the following to locate all rows of that matrix that are equal to 3:

loc(m==3)

This returns the following result

[2,3,7]

which is a matrix of row numbers of m that are equal to 3.

If you leave off the loc function and just use m==3, then you get a matrix of 1's and 0's, with a 1 indicating the value is equal to 3.

Re: Convert Matrix to List?

mpb — Fri, 29 Oct 2010 18:50:30 GMT

Here's the syntax for converting a 1D matrix to a list:

cell_list = as list (cell_matrix);

Re: Convert Matrix to List?

pmroz — Fri, 29 Oct 2010 19:06:50 GMT

Thank you very much for your responses. It's easy when you know how!