NetLogo 7.0.0-beta2:

matrix:set-row

matrix:set-row matrix row-i simple-list

Changes the given matrix matrix by replacing the row at row-i with the contents of the simple (not nested) NetLogo list simple-list. The simple-list must have a length equal to the number of columns in the matrix, i.e., the matrix row length.

Take me to the full Matrix Extension Dictionary