fun_dynamic_xam.py#

Python: Using Dynamic Parameters: Example and Test#

import numpy
import cppad_py
def fun_dynamic_xam() :
   ok  = True
   nx  = 2
   nd  = 2
   #
   # value of independent variables during recording
   x = numpy.empty(nx, dtype=float)
   x[0] = 1.0
   x[1] = 2.0
   #
   # value of independent dynamic parameters during recording
   dynamic = numpy.empty(nd, dtype=float)
   dynamic[0] = 3.0
   dynamic[1] = 4.0
   #
   # start recording
   (ax, adynamic) = cppad_py.independent(x, dynamic)
   #
   # create another dynamic paramerer
   adyn  = adynamic[0] + adynamic[1]
   #
   # create another variable
   avar  = ax[0] + ax[1] + adyn
   #
   # create f(x) = x[0] + x[1] + dynamic[0] + dynamic[1]
   ay    = numpy.empty(1, dtype=cppad_py.a_double)
   ay[0] = avar
   f     = cppad_py.d_fun(ax, ay)
   #
   # check some properties of f
   ok = ok and f.size_domain() == nx
   ok = ok and f.size_order()  == 0
   #
   # zero order forward mode using same values as during the recording
   y  = f.forward(0, x)
   ok = ok and y[0] == (x[0] + x[1] + dynamic[0] + dynamic[1])
   #
   #  zero order forward mode using different value for dynamic parameters
   dynamic[0] = dynamic[0] + 1.0
   dynamic[1] = dynamic[1] + 1.0
   f.new_dynamic(dynamic)
   y   = f.forward(0, x)
   ok  = ok and y[0] == (x[0] + x[1] + dynamic[0] + dynamic[1])
   #
   return ok