# Last edited on 2021-07-31 16:32:06 by jstolfi

from gauss_bell import gauss_bell
  
def basis_2d_gauss_eval(c, r, A, p):
  # Evaluats at the point {p} the linear combination of with coefficients {A[...]}
  # of the Gauss bell basis functions whose centroids are in {c} and whose radii are in {r}.
  #
  # Both the point {p} and the centroid and radius of each basis element
  # must be 2-tuples of floats. The parameter {A} must be a list of floats
  # with the same length as {c} and {r}.

  nb = len(c);
  sum = 0
  for i in range(nb):
    cxi,cyi = c[i]
    rxi,ryi = r[i]
    Ai = A[i]
    gx = gauss_bell((p[0]-cxi)/rxi)
    gy = gauss_bell((p[1]-cyi)/ryi)
    sum += Ai*gx*gy
  return sum
  # ----------------------------------------------------------------------