什么是Matlab的fminunc函数的R等价物？

In order to compute the optimal theta e.g. in logistic regression, I have to create a costFunction (the function to be minimized) which is then passed to fminunc in order to obtain the optimal theta. Also, if the gradient of costFunction can be computed, I set the 'GradObj' option to 'on' usingIn order to compute the optimal theta e.g. in l