I have a function that accepts a  void* as a parameter

Im trying to convert this to use as the void*

float trainingData[4][2] = { {501, 10}, {255, 10}, {501, 255}, {10, 501} };

this is how i do a void* 1d array

  float labels[4] = {1.0, -1.0, -1.0, -1.0};

(labels (foreign-alloc :float :initial-contents '(1.0 -1.0 -1.0 -1.0)))

so how  do i do the 2d array