#! /usr/bin/env python3 # def d1mach ( i ): #*****************************************************************************80 # ## d1mach() returns double precision real machine constants. # # Discussion: # # Assume that double precision real numbers are stored with a mantissa # of T digits in base B, with an exponent whose value must lie # between EMIN and EMAX. Then for values of I between 1 and 5, # d1mach will return the following values: # # d1mach(1) = B^(EMIN-1), the smallest positive magnitude. # d1mach(2) = B^EMAX*(1-B^(-T)), the largest magnitude. # d1mach(3) = B^(-T), the smallest relative spacing. # d1mach(4) = B^(1-T), the largest relative spacing. # d1mach(5) = log10(B) # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # Original FORTRAN77 version by Phyllis Fox, Andrew Hall, Norman Schryer # Python version by John Burkardt. # # Reference: # # Phyllis Fox, Andrew Hall, Norman Schryer, # Algorithm 528, # Framework for a Portable Library, # ACM Transactions on Mathematical Software, # Volume 4, Number 2, June 1978, page 176-188. # # Input: # # integer I, chooses the parameter to be returned. # 1 <= I <= 5. # # Output: # # real VALUE, the value of the chosen parameter. # if ( i < 1 ): print ( '' ) print ( 'd1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 5.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'd1mach - Fatal error!' ) elif ( i == 1 ): value = 1.112536929253601E-308 elif ( i == 2 ): value = 4.494232837155789E+307 elif ( i == 3 ): value = 1.110223024625157E-016 elif ( i == 4 ): value = 2.220446049250313E-016 elif ( i == 5 ): value = 0.301029995663981 elif ( 5 < i ): print ( '' ) print ( 'd1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 5.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'd1mach - Fatal error!' ) return value def d1mach_test ( ): #*****************************************************************************80 # ## d1mach_test() reports the constants returned by d1mach. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'd1mach_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' d1mach reports the value of constants associated' ) print ( ' with real double precision computer arithmetic.' ) print ( '' ) print ( ' Assume that double precision numbers are stored ' ) print ( ' with a mantissa of T digits in base B, with an' ) print ( ' exponent whose value must lie between EMIN and EMAX.' ) print ( '' ) print ( ' For input arguments of 1 <= I <= 5,' ) print ( ' d1mach will return the following values:' ) print ( '' ) print ( ' d1mach(1) = B^(EMIN-1), the smallest positive magnitude.' ) print ( ' %26.16e' % ( d1mach ( 1 ) ) ) print ( '' ) print ( ' d1mach(2) = B^EMAX*(1-B^(-T)), the largest magnitude.' ) print ( ' %26.16e' % ( d1mach ( 2 ) ) ) print ( '' ) print ( ' d1mach(3) = B^(-T), the smallest relative spacing.' ) print ( ' %26.16e' % ( d1mach ( 3 ) ) ) print ( '' ) print ( ' d1mach(4) = B^(1-T), the largest relative spacing.' ) print ( ' %26.16e' % ( d1mach ( 4 ) ) ) print ( '' ) print ( ' d1mach(5) = log10(B).' ) print ( ' %26.16e' % ( d1mach ( 5 ) ) ) # # Terminate. # print ( '' ) print ( 'd1mach_test' ) print ( ' Normal end of execution.' ) return def i1mach ( i ): #*****************************************************************************80 # ## i1mach() returns integer machine constants. # # Discussion: # # Input/output unit numbers. # # i1mach(1) = the standard input unit. # i1mach(2) = the standard output unit. # i1mach(3) = the standard punch unit. # i1mach(4) = the standard error message unit. # # Words. # # i1mach(5) = the number of bits per integer storage unit. # i1mach(6) = the number of characters per integer storage unit. # # Integers. # # Assume integers are represented in the S digit base A form: # # Sign * (X(S-1)*A^(S-1) + ... + X(1)*A + X(0)) # # where 0 <= X(1:S-1) < A. # # i1mach(7) = A, the base. # i1mach(8) = S, the number of base A digits. # i1mach(9) = A^S-1, the largest integer. # # Floating point numbers # # Assume floating point numbers are represented in the T digit # base B form: # # Sign * (B^E) * ((X(1)/B) + ... + (X(T)/B^T) ) # # where 0 <= X(I) < B for I=1 to T, 0 < X(1) and EMIN <= E <= EMAX. # # i1mach(10) = B, the base. # # Single precision # # i1mach(11) = T, the number of base B digits. # i1mach(12) = EMIN, the smallest exponent E. # i1mach(13) = EMAX, the largest exponent E. # # Double precision # # i1mach(14) = T, the number of base B digits. # i1mach(15) = EMIN, the smallest exponent E. # i1mach(16) = EMAX, the largest exponent E. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # Original FORTRAN77 version by Phyllis Fox, Andrew Hall, Norman Schryer # Python version by John Burkardt. # # Reference: # # Phyllis Fox, Andrew Hall, Norman Schryer, # Algorithm 528, # Framework for a Portable Library, # ACM Transactions on Mathematical Software, # Volume 4, Number 2, June 1978, page 176-188. # # Input: # # integer I, chooses the parameter to be returned. # 1 <= I <= 16. # # Output: # # integer VALUE, the value of the chosen parameter. # if ( i < 1 ): print ( '' ) print ( 'i1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 16.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'i1mach - Fatal error!' ) elif ( i == 1 ): value = 5 elif ( i == 2 ): value = 6 elif ( i == 3 ): value = 7 elif ( i == 4 ): value = 6 elif ( i == 5 ): value = 32 elif ( i == 6 ): value = 4 elif ( i == 7 ): value = 2 elif ( i == 8 ): value = 31 elif ( i == 9 ): value = 2147483647 elif ( i == 10 ): value = 2 elif ( i == 11 ): value = 24 elif ( i == 12 ): value = -125 elif ( i == 13 ): value = 128 elif ( i == 14 ): value = 53 elif ( i == 15 ): value = -1021 elif ( i == 16 ): value = 1024 elif ( 16 < i ): print ( '' ) print ( 'i1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 16.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'i1mach - Fatal error!' ) return value def i1mach_test ( ): #*****************************************************************************80 # ## i1mach_test() reports the constants returned by i1mach. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'i1mach_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' i1mach reports the value of constants associated' ) print ( ' with integer computer arithmetic.' ) print ( '' ) print ( ' Numbers associated with input/output units:' ) print ( '' ) print ( ' i1mach(1) = the standard input unit.' ) print ( ' %d' % ( i1mach ( 1 ) ) ) print ( '' ) print ( ' i1mach(2) = the standard output unit.' ) print ( ' %d' % ( i1mach ( 2 ) ) ) print ( '' ) print ( ' i1mach(3) = the standard punch unit.' ) print ( ' %d' % ( i1mach ( 3 ) ) ) print ( '' ) print ( ' i1mach(4) = the standard error message unit.' ) print ( ' %d' % ( i1mach ( 4 ) ) ) print ( '' ) print ( ' Numbers associated with words:' ) print ( '' ) print ( ' i1mach(5) = the number of bits per integer.' ) print ( ' %d' % ( i1mach ( 5 ) ) ) print ( '' ) print ( ' i1mach(6) = the number of characters per integer.' ) print ( ' %d' % ( i1mach ( 6 ) ) ) print ( '' ) print ( ' Numbers associated with integer values:' ) print ( '' ) print ( ' Assume integers are represented in the S digit' ) print ( ' base A form:' ) print ( '' ) print ( ' Sign * (X(S-1)*A^(S-1) + ... + X(1)*A + X(0))' ) print ( '' ) print ( ' where the digits X satisfy 0 <= X(1:S-1) < A.' ) print ( '' ) print ( ' i1mach(7) = A, the base.' ) print ( ' %d' % ( i1mach ( 7 ) ) ) print ( '' ) print ( ' i1mach(8) = S, the number of base A digits.' ) print ( ' %d' % ( i1mach ( 8 ) ) ) print ( '' ) print ( ' i1mach(9) = A^S-1, the largest integer.' ) print ( ' %d' % ( i1mach ( 9 ) ) ) print ( '' ) print ( ' Numbers associated with floating point values:' ) print ( '' ) print ( ' Assume floating point numbers are represented ' ) print ( ' in the T digit base B form:' ) print ( '' ) print ( ' Sign * (B^E) * ((X(1)/B) + ... + (X(T)/B^T) )' ) print ( '' ) print ( ' where' ) print ( '' ) print ( ' 0 <= X(1:T) < B,' ) print ( ' 0 < X(1) (unless the value being represented is 0),' ) print ( ' EMIN <= E <= EMAX.' ) print ( '' ) print ( ' i1mach(10) = B, the base.' ) print ( ' %d' % ( i1mach ( 10 ) ) ) print ( '' ) print ( ' Numbers associated with single precision values:' ) print ( '' ) print ( ' i1mach(11) = T, the number of base B digits.' ) print ( ' %d' % ( i1mach ( 11 ) ) ) print ( '' ) print ( ' i1mach(12) = EMIN, the smallest exponent E.' ) print ( ' %d' % ( i1mach ( 12 ) ) ) print ( '' ) print ( ' i1mach(13) = EMAX, the largest exponent E.' ) print ( ' %d' % ( i1mach ( 13 ) ) ) print ( '' ) print ( ' Numbers associated with double precision values:' ) print ( '' ) print ( ' i1mach(14) = T, the number of base B digits.' ) print ( ' %d' % ( i1mach ( 14 ) ) ) print ( '' ) print ( ' i1mach(15) = EMIN, the smallest exponent E.' ) print ( ' %d' % ( i1mach ( 15 ) ) ) print ( '' ) print ( ' i1mach(16) = EMAX, the largest exponent E.' ) print ( ' %d' % ( i1mach ( 16 ) ) ) # # Terminate. # print ( '' ) print ( 'i1mach_test' ) print ( ' Normal end of execution.' ) return def machine_test ( ): #*****************************************************************************80 # ## machine_test() tests machine(). # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'machine_test:' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' Test machine()' ) d1mach_test ( ) i1mach_test ( ) r1mach_test ( ) # # Terminate. # print ( '' ) print ( 'MACHINE_test:' ) print ( ' Normal end of execution.' ) return def r1mach ( i ): #*****************************************************************************80 # ## r1mach() returns single precision real machine constants. # # Discussion: # # Assume that single precision real numbers are stored with a mantissa # of T digits in base B, with an exponent whose value must lie # between EMIN and EMAX. Then for values of I between 1 and 5, # r1mach will return the following values: # # r1mach(1) = B^(EMIN-1), the smallest positive magnitude. # r1mach(2) = B^EMAX*(1-B^(-T)), the largest magnitude. # r1mach(3) = B^(-T), the smallest relative spacing. # r1mach(4) = B^(1-T), the largest relative spacing. # r1mach(5) = log10(B) # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # Original FORTRAN77 version by Phyllis Fox, Andrew Hall, Norman Schryer # Python version by John Burkardt. # # Reference: # # Phyllis Fox, Andrew Hall, Norman Schryer, # Algorithm 528, # Framework for a Portable Library, # ACM Transactions on Mathematical Software, # Volume 4, Number 2, June 1978, page 176-188. # # Input: # # integer I, chooses the parameter to be returned. # 1 <= I <= 5. # # Output: # # real VALUE, the value of the chosen parameter. # if ( i < 1 ): print ( '' ) print ( 'r1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 5.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'r1mach - Fatal error!' ) elif ( i == 1 ): value = 1.1754944E-38 elif ( i == 2 ): value = 3.4028235E+38 elif ( i == 3 ): value = 5.9604645E-08 elif ( i == 4 ): value = 1.1920929E-07 elif ( i == 5 ): value = 0.3010300 elif ( 5 < i ): print ( '' ) print ( 'r1mach - Fatal error!' ) print ( ' The input argument I is out of bounds.' ) print ( ' Legal values satisfy 1 <= I <= 5.' ) print ( ' I = %d' % ( i ) ) raise Exception ( 'r1mach - Fatal error!' ) return value def r1mach_test ( ): #*****************************************************************************80 # ## r1mach_test() reports the constants returned by r1mach. # # Licensing: # # This code is distributed under the MIT license. # # Modified: # # 04 April 2015 # # Author: # # John Burkardt # import platform print ( '' ) print ( 'r1mach_test' ) print ( ' Python version: %s' % ( platform.python_version ( ) ) ) print ( ' r1mach reports the value of constants associated' ) print ( ' with real single precision computer arithmetic.' ) print ( '' ) print ( ' Assume that single precision numbers are stored ' ) print ( ' with a mantissa of T digits in base B, with an ' ) print ( ' exponent whose value must lie between EMIN and EMAX.' ) print ( '' ) print ( ' For input arguments of 1 <= I <= 5,' ) print ( ' r1mach will return the following values:' ) print ( '' ) print ( ' r1mach(1) = B^(EMIN-1), the smallest positive magnitude.' ) print ( ' %26.16e' % ( r1mach ( 1 ) ) ) print ( '' ) print ( ' r1mach(2) = B^EMAX*(1-B^(-T)), the largest magnitude.' ) print ( ' %26.16e' % ( r1mach ( 2 ) ) ) print ( '' ) print ( ' r1mach(3) = B^(-T), the smallest relative spacing.' ) print ( ' %26.16e' % ( r1mach ( 3 ) ) ) print ( '' ) print ( ' r1mach(4) = B^(1-T), the largest relative spacing.' ) print ( ' %26.16e' % ( r1mach ( 4 ) ) ) print ( '' ) print ( ' r1mach(5) = log10(B).' ) print ( ' %26.16e' % ( r1mach ( 5 ) ) ) # # Terminate. # print ( '' ) print ( 'r1mach_test' ) print ( ' Normal end of execution.' ) 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 None if ( __name__ == '__main__' ): timestamp ( ) machine_test ( ) timestamp ( )