mons/math3/analysis/MultivariateVectorFunction.html" title="interface in org.apache.commons.math3.analysis"><code>non-differentiable multivariate vectorial function</code></a> by converting it to a <a href="../../../../../org/apache/commons/math3/analysis/MultivariateFunction.html" title="interface in org.apache.commons.math3.analysis"><code>non-differentiable multivariate
 real function</code></a> thanks to the <a href="../../../../../org/apache/commons/math3/optimization/LeastSquaresConverter.html" title=