#! /usr/bin/env python3 # def cube01_monomial_integral ( e ): #*****************************************************************************80 # ## cube01_monomial_integral(): integrals over the unit cube in 3D. # # Discussion: # # The integration region is # # 0 <= X <= 1, # 0 <= Y <= 1, # 0 <= Z <= 1. # # The monomial is F(X,Y,Z) = X^E(1) * Y^E(2) * Z^E(3). # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 18 January 2014 # # Author: # # John Burkardt # # Reference: # # Philip Davis, Philip Rabinowitz, # Methods of Numerical Integration, # Second Edition, # Academic Press, 1984, page 263. # # Input: # # integer E(3), the exponents. Each exponent must be nonnegative. # # Output: # # real INTEGRAL, the integral. # m = 3 if ( e[0] < 0 or e[1] < 0 or e[2] < 0 ): print ( '' ) print ( 'cube01_monomial_integral - Fatal error!' ) print ( ' All exponents must be nonnegative.' ) raise Exception ( 'cube01_monomial_integral - Fatal error!' ) integral = 1.0 for i in range ( 0, m ): integral = integral / float ( e[i] + 1 ) return integral def cube01_monomial_integral_test ( ): #*****************************************************************************80 # ## cube01_monomial_integral_test tests cube01_monomial_integral. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # import numpy as np import platform m = 3 n = 4192 test_num = 20 print ( '' ) print ( 'cube01_monomial_integral_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' cube01_monomial_integral computes the integral of a monomial' ) print ( ' within the interior of the unit cube in 3D.' ) print ( ' Compare with a Monte Carlo estimate.' ) # # Get sample points. # x = cube01_sample ( n ) print ( '' ) print ( ' Number of sample points used is %d' % ( n ) ) # # Randomly choose exponents. # print ( '' ) print ( ' Ex Ey Ez MC-Estimate Exact Error' ) print ( '' ) for test in range ( 0, test_num ): e = np.random.random_integers ( 0, 7, size = m ) value = monomial_value ( m, n, e, x ) result = cube01_volume ( ) * np.sum ( value ) / float ( n ) exact = cube01_monomial_integral ( e ) error = abs ( result - exact ) print ( ' %2d %2d %2d %14.6g %14.6g %10.2g' \ % ( e[0], e[1], e[2], result, exact, error ) ) # # Terminate. # print ( '' ) print ( 'cube01_monomial_integral_test:' ) print ( ' Normal end of execution.' ) return def cube01_sample ( n ): #*****************************************************************************80 # ## cube01_sample samples points in the unit cube in 3D. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # # Input: # # integer N, the number of points. # # Output: # # real X(3,N), the points. # import numpy as np x = np.random.rand ( 3, n ) return x def cube01_sample_test ( ): #*****************************************************************************80 # ## cube01_sample_test tests cube01_sample. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'cube01_sample_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' cube01_sample samples the unit cube.' ) n = 10 x = cube01_sample ( n ) r8mat_transpose_print ( 3, n, x, ' Sample points in the unit cube.' ) # # Terminate. # print ( '' ) print ( 'cube01_sample_test' ) print ( ' Normal end of execution.' ) return def cube01_volume ( ): #*****************************************************************************80 # ## cube01_volume returns the volume of the unit cube in 3D. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # # Output: # # real VALUE, the volume. # value = 1.0; return value def cube01_volume_test ( ) : #*****************************************************************************80 # ## cube01_volume tests cube01_volume. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'cube01_volume_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' cube01_volume returns the volume of the unit cube.' ) value = cube01_volume ( ) print ( '' ) print ( ' cube01_volume() = %g' % ( value ) ) # # Terminate. # print ( '' ) print ( 'cube01_volume_test' ) print ( ' Normal end of execution.' ) return def cube_integrals_test ( ): #*****************************************************************************80 # ## cube_integrals_test() tests cube_integrals(). # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 21 June 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'cube_integrals_test():' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' Test cube_integrals().' ) # # Library functions. # cube01_monomial_integral_test ( ) cube01_sample_test ( ) cube01_volume_test ( ) # # Terminate. # print ( '' ) print ( 'cube_integrals_test():' ) print ( ' Normal end of execution.' ) return def i4vec_print ( n, a, title ): #*****************************************************************************80 # ## i4vec_print prints an I4VEC. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 31 August 2014 # # Author: # # John Burkardt # # Input: # # integer N, the dimension of the vector. # # integer A(N), the vector to be printed. # # string TITLE, a title. # print ( '' ) print ( title ) print ( '' ) for i in range ( 0, n ): print ( '%6d %6d' % ( i, a[i] ) ) return def i4vec_transpose_print ( n, a, title ): #*****************************************************************************80 # ## i4vec_transpose_print prints an I4VEC "transposed". # # Example: # # A = (/ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 /) # TITLE = 'My vector: ' # # My vector: # # 1 2 3 4 5 # 6 7 8 9 10 # 11 # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 08 September 2018 # # Author: # # John Burkardt # # Input: # # integer N, the number of components of the vector. # # integer A(N), the vector to be printed. # # string TITLE, a title. # if ( 0 < len ( title ) ): print ( title, end = '' ) if ( 0 < n ): for i in range ( 0, n ): print ( ' %d' % ( a[i] ), end = '' ) if ( ( i + 1 ) % 20 == 0 or i == n - 1 ): print ( '' ) else: print ( '(empty vector)' ) return def monomial_value ( m, n, e, x ): #*****************************************************************************80 # ## monomial_value() evaluates a monomial. # # Discussion: # # This routine evaluates a monomial of the form # # product ( 1 <= i <= m ) x(i)^e(i) # # The combination 0.0^0, if encountered, is treated as 1.0. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 07 April 2015 # # Author: # # John Burkardt # # Input: # # integer M, the spatial dimension. # # integer N, the number of evaluation points. # # integer E(M), the exponents. # # real X(M,N), the point coordinates. # # Output: # # real V(N), the monomial values. # import numpy as np v = np.ones ( n ) for i in range ( 0, m ): if ( 0 != e[i] ): for j in range ( 0, n ): if ( x[i,j] == 0.0 ): v[j] = 0.0 else: v[j] = v[j] * x[i,j] ** e[i] return v def r8mat_print ( m, n, a, title ): #*****************************************************************************80 # ## r8mat_print prints an R8MAT. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 31 August 2014 # # Author: # # John Burkardt # # Input: # # integer M, the number of rows in A. # # integer N, the number of columns in A. # # real A(M,N), the matrix. # # string TITLE, a title. # r8mat_print_some ( m, n, a, 0, 0, m - 1, n - 1, title ) return def r8mat_print_some ( m, n, a, ilo, jlo, ihi, jhi, title ): #*****************************************************************************80 # ## r8mat_print_some prints out a portion of an R8MAT. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 10 February 2015 # # Author: # # John Burkardt # # Input: # # integer M, N, the number of rows and columns of the matrix. # # real A(M,N), an M by N matrix to be printed. # # integer ILO, JLO, the first row and column to print. # # integer IHI, JHI, the last row and column to print. # # string TITLE, a title. # incx = 5 print ( '' ) print ( title ) if ( m <= 0 or n <= 0 ): print ( '' ) print ( ' (None)' ) return for j2lo in range ( max ( jlo, 0 ), min ( jhi + 1, n ), incx ): j2hi = j2lo + incx - 1 j2hi = min ( j2hi, n ) j2hi = min ( j2hi, jhi ) print ( '' ) print ( ' Col: ', end = '' ) for j in range ( j2lo, j2hi + 1 ): print ( '%7d ' % ( j ), end = '' ) print ( '' ) print ( ' Row' ) i2lo = max ( ilo, 0 ) i2hi = min ( ihi, m ) for i in range ( i2lo, i2hi + 1 ): print ( '%7d :' % ( i ), end = '' ) for j in range ( j2lo, j2hi + 1 ): print ( '%12g ' % ( a[i,j] ), end = '' ) print ( '' ) return def r8mat_transpose_print ( m, n, a, title ): #*****************************************************************************80 # ## r8mat_transpose_print prints an R8MAT, transposed. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 31 August 2014 # # Author: # # John Burkardt # # Input: # # integer M, the number of rows in A. # # integer N, the number of columns in A. # # real A(M,N), the matrix. # # string TITLE, a title. # r8mat_transpose_print_some ( m, n, a, 0, 0, m - 1, n - 1, title ) return def r8mat_transpose_print_some ( m, n, a, ilo, jlo, ihi, jhi, title ): #*****************************************************************************80 # ## r8mat_transpose_print_some prints a portion of an R8MAT, transposed. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 13 November 2014 # # Author: # # John Burkardt # # Input: # # integer M, N, the number of rows and columns of the matrix. # # real A(M,N), an M by N matrix to be printed. # # integer ILO, JLO, the first row and column to print. # # integer IHI, JHI, the last row and column to print. # # string TITLE, a title. # incx = 5 print ( '' ) print ( title ) if ( m <= 0 or n <= 0 ): print ( '' ) print ( ' (None)' ) return for i2lo in range ( max ( ilo, 0 ), min ( ihi, m - 1 ), incx ): i2hi = i2lo + incx - 1 i2hi = min ( i2hi, m - 1 ) i2hi = min ( i2hi, ihi ) print ( '' ) print ( ' Row: ', end = '' ) for i in range ( i2lo, i2hi + 1 ): print ( '%7d ' % ( i ), end = '' ) print ( '' ) print ( ' Col' ) j2lo = max ( jlo, 0 ) j2hi = min ( jhi, n - 1 ) for j in range ( j2lo, j2hi + 1 ): print ( '%7d :' % ( j ), end = '' ) for i in range ( i2lo, i2hi + 1 ): print ( '%12g ' % ( a[i,j] ), end = '' ) print ( '' ) return def timestamp ( ): #*****************************************************************************80 # ## timestamp() prints the date as a timestamp. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 06 April 2013 # # Author: # # John Burkardt # import time t = time.time ( ) print ( time.ctime ( t ) ) return if ( __name__ == '__main__' ): timestamp ( ) cube_integrals_test ( ) timestamp ( )