If I want to apply PSO for a 20 matrices each matrix of 1x100 dimensions , what will be the nvar ,npop although the fittnes function has two variable,?

[Walter Roberson]

You cannot apply PSO to a matrix. You can apply PSO to a function. You can use matrices to initialize the population to be used with a function. The matrices would have one of the dimensions the same as the number of variables.