<< CMA-ES Optimization Toolbox CMA-ES Optimization Toolbox cma_new >>
CMA-ES Optimization Toolbox >> CMA-ES Optimization Toolbox > cma_ask

cma_ask

Get candidate solutions from cma optimizer

Calling Sequence

X = cma_ask(es,lambda,mod)
X = cma_ask(es,lambda) // the same with mod=0
X = cma_ask(es) // the same with lambda=es.sp.lambda
X = %cma_ask(es) // the same

Parameters

es

cma object from cma_new

lambda

number of column vectors to be returned

mod

default is 0. With mod set to one, always a list of vector(s) is returned, even for lambda=1.

X

list of column vectors, new candidate solutions. If lambda equals to one and with default mod 0, a single vector (not a list with one vector) is returned.

Description

Examples

clear param
param.x0 = ones(8,1);
param.sigma0 = 0.5;
es = cma_new(param);
while ~ cma_stop(es)
  X = cma_ask(es);    // return a list with lambda column vectors
  y = [];             // just in case
  for i = 1:length(X) // evaluate all lambda candidate solution
    y(i) = fitfun(X(i)); // must return a scalar
    // re-sampling of infeasible solution if f==%nan (rejection method)
    while isnan(y(i))
      X(i) = cma_ask(es, 1);
      y(i) = fitfun(X(i));
    end
  end
  // do not use modified X here, unless you very well know what you do
  es = cma_tell(es, X, y');  // finish iteration
end

See Also

Authors

Nikolaus Hansen

Bibliography

Used Functions


Report an issue
<< CMA-ES Optimization Toolbox CMA-ES Optimization Toolbox cma_new >>