def wathen_test07(): #*****************************************************************************80 # ## WATHEN_TEST06 assembles, factor and solves using WATHEN_CSC + CG_CSC. # # Licensing: # # This code is distributed under the GNU LGPL license. # # Modified: # # 04 September 2014 # # Author: # # John Burkardt # import numpy as np from cg_csc import cg_csc from numpy.linalg import norm from r8vec_uniform_01 import r8vec_uniform_01 from wathen_csc import wathen_csc from wathen_order import wathen_order print '' print 'WATHEN_TEST07' print ' Assemble, factor and solve a Wathen system' print ' defined by WATHEN_CSC and CG_CSC.' print '' nx = 2 ny = 2 print ' Elements in X direction NX = %d' % (nx) print ' Elements in Y direction NY = %d' % (ny) print ' Number of elements = %d' % (nx * ny) # # Compute the number of unknowns. # n = wathen_order(nx, ny) print ' Number of nodes N = %d' % (n) # # Set up a random solution X1. # seed = 123456789 x1, seed = r8vec_uniform_01(n, seed) # # Compute the matrix. # seed = 123456789 a, seed = wathen_csc(nx, ny, seed) # # Compute the corresponding right hand side B. # b = a.dot(x1) # # Solve the linear system. # x2 = np.ones(n) x2 = cg_csc(n, a, b, x2) # # Compute the maximum solution error. # e = norm(x1 - x2) print ' Maximum solution error is %g' % (e) return
def wathen_test04 ( ): #*****************************************************************************80 # ## WATHEN_TEST04 times WATHEN_CSC assembly and solution. # # Licensing: # # This code is distributed under the GNU LGPL license. # # Modified: # # 04 September 2014 # # Author: # # John Burkardt # import numpy as np import scipy.sparse.linalg as ssl import time from numpy.linalg import norm from r8vec_uniform_01 import r8vec_uniform_01 from wathen_csc import wathen_csc from wathen_order import wathen_order print '' print 'WATHEN_TEST04' print ' For various problem sizes,' print ' time the assembly and factorization of a Wathen system' print ' using the WATHEN_CSC function.' print '' print ' NX Elements Nodes Assembly ', print 'Factor Error' print '' nx = 1 ny = 1 for test in range ( 0, 7 ): # # Compute the number of unknowns. # n = wathen_order ( nx, ny ) # # Set up a random solution X1. # seed = 123456789 x1, seed = r8vec_uniform_01 ( n, seed ) # # Compute the matrix. # seed = 123456789 t0 = time.clock ( ) a, seed = wathen_csc ( nx, ny, seed ) t1 = ( time.clock ( ) - t0 ) # # Compute the corresponding right hand side B. # b = a.dot ( x1 ) # # Solve the system. # t0 = time.clock ( ) x2 = ssl.spsolve ( a, b ) t2 = ( time.clock ( ) - t0 ) # # Compute the norm of the solution error. # e = norm ( x1 - x2 ) # # Report. # print ' %4d %4d %6d %10.2e %10.2e %10.2e' % \ ( nx, nx * ny, n, t1, t2, e ) # # Ready for next iteration. # nx = nx * 2 ny = ny * 2 return
def wathen_test07 ( ): #*****************************************************************************80 # ## WATHEN_TEST06 assembles, factor and solves using WATHEN_CSC + CG_CSC. # # Licensing: # # This code is distributed under the GNU LGPL license. # # Modified: # # 04 September 2014 # # Author: # # John Burkardt # import numpy as np from cg_csc import cg_csc from numpy.linalg import norm from r8vec_uniform_01 import r8vec_uniform_01 from wathen_csc import wathen_csc from wathen_order import wathen_order print '' print 'WATHEN_TEST07' print ' Assemble, factor and solve a Wathen system' print ' defined by WATHEN_CSC and CG_CSC.' print '' nx = 2 ny = 2 print ' Elements in X direction NX = %d' % ( nx ) print ' Elements in Y direction NY = %d' % ( ny ) print ' Number of elements = %d' % ( nx * ny ) # # Compute the number of unknowns. # n = wathen_order ( nx, ny ) print ' Number of nodes N = %d' % ( n ) # # Set up a random solution X1. # seed = 123456789 x1, seed = r8vec_uniform_01 ( n, seed ) # # Compute the matrix. # seed = 123456789 a, seed = wathen_csc ( nx, ny, seed ) # # Compute the corresponding right hand side B. # b = a.dot ( x1 ) # # Solve the linear system. # x2 = np.ones ( n ) x2 = cg_csc ( n, a, b, x2 ) # # Compute the maximum solution error. # e = norm ( x1 - x2 ) print ' Maximum solution error is %g' % ( e ) return
def wathen_test04(): #*****************************************************************************80 # ## WATHEN_TEST04 times WATHEN_CSC assembly and solution. # # Licensing: # # This code is distributed under the GNU LGPL license. # # Modified: # # 04 September 2014 # # Author: # # John Burkardt # import numpy as np import scipy.sparse.linalg as ssl import time from numpy.linalg import norm from r8vec_uniform_01 import r8vec_uniform_01 from wathen_csc import wathen_csc from wathen_order import wathen_order print '' print 'WATHEN_TEST04' print ' For various problem sizes,' print ' time the assembly and factorization of a Wathen system' print ' using the WATHEN_CSC function.' print '' print ' NX Elements Nodes Assembly ', print 'Factor Error' print '' nx = 1 ny = 1 for test in range(0, 7): # # Compute the number of unknowns. # n = wathen_order(nx, ny) # # Set up a random solution X1. # seed = 123456789 x1, seed = r8vec_uniform_01(n, seed) # # Compute the matrix. # seed = 123456789 t0 = time.clock() a, seed = wathen_csc(nx, ny, seed) t1 = (time.clock() - t0) # # Compute the corresponding right hand side B. # b = a.dot(x1) # # Solve the system. # t0 = time.clock() x2 = ssl.spsolve(a, b) t2 = (time.clock() - t0) # # Compute the norm of the solution error. # e = norm(x1 - x2) # # Report. # print ' %4d %4d %6d %10.2e %10.2e %10.2e' % \ ( nx, nx * ny, n, t1, t2, e ) # # Ready for next iteration. # nx = nx * 2 ny = ny * 2 return