code: def _f_simplex(gamma, v, lambda_v, x):
      return 0.5 * lambda_v * np.dot((v - x).T, v - x) - np.sum(
          gamma * np.log(x)
      )
  
file_path: cornac/cornac/models/ctr/ctr.py
imports: import numpy
  from ...utils import get_rng
label_desc: Use image node_id 1 for calling a global function with example usage: _f_simplex(gamma, v, lambda_v, x) and returns: unknown