Mutation function for the ES strategy parameter sigma.
spotAlgEsStratMutation(strat, tau0, tau, sigmaRestart, sigmaInit)
Strategy parameter (sigma), can be a vector or a single number
the global/general step size multiplier for self adaption
the step size multiplier for self adaption in each dimension
sigma values are reset to initial values when a uniformly distributed random number is smaller than sigmaRestart
initial sigma value
number s
- s
is the new sigma value