https://ask.sagemath.org/question/23572/does-sage-have-a-function-that-generates-a-random-double-stochastic-matrix-in-which-the-elements-of-each-row-and-each-column-add-to-one/?sort=latest
Does Sage have a function that generates a random double stochastic matrix in which the elements of...
Each element is a random probability and no elements are negative.
double stochastic matrixthe elementssagefunctiongenerates