subroutine get_seed ( seed ) c*********************************************************************72 c cc get_seed() returns a seed for the random number generator. c c Discussion: c c The seed depends on the current time, and ought to be (slightly) c different every millisecond. Thus, calling this routine several c times in succession will probably return the SAME seed, but c calling it a few minutes or days apart will turn a suitably c "random" seed. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 11 January 2007 c c Author: c c John Burkardt c c Parameters: c c Output, integer SEED, a pseudorandom seed value. c implicit none integer day integer hour integer i4_huge parameter ( i4_huge = 2147483647 ) integer milli integer minute integer month integer second integer seed double precision temp character * ( 10 ) time character * ( 8 ) date integer year call date_and_time ( date, time ) read ( date, '(i4,i2,i2)' ) year, month, day read ( time, '(i2,i2,i2,1x,i3)' ) hour, minute, second, milli temp = 0.0D+00 temp = temp + dble ( month - 1 ) / 11.0D+00 temp = temp + dble ( day - 1 ) / 30.0D+00 temp = temp + dble ( hour ) / 23.0D+00 temp = temp + dble ( minute ) / 59.0D+00 temp = temp + dble ( second ) / 59.0D+00 temp = temp + dble ( milli ) / 999.0D+00 temp = temp / 6.0D+00 c c Force 0 < TEMP <= 1. c 10 continue if ( temp .le. 0.0D+00 ) then temp = temp + 1.0D+00 go to 10 end if 20 continue if ( 1.0D+00 .lt. temp ) then temp = temp - 1.0D+00 go to 20 end if seed = int ( dble ( i4_huge ) * temp ) c c Never use a seed of 0 or maximum integer. c if ( seed .eq. 0 ) then seed = 1 end if if ( seed .eq. i4_huge ) then seed = seed - 1 end if return end subroutine get_unit ( iunit ) c*********************************************************************72 c cc GET_UNIT returns a free FORTRAN unit number. c c Discussion: c c A "free" FORTRAN unit number is a value between 1 and 99 which c is not currently associated with an I/O device. A free FORTRAN unit c number is needed in order to open a file with the OPEN command. c c If IUNIT = 0, then no free FORTRAN unit could be found, although c all 99 units were checked (except for units 5, 6 and 9, which c are commonly reserved for console I/O). c c Otherwise, IUNIT is a value between 1 and 99, representing a c free FORTRAN unit. Note that GET_UNIT assumes that units 5 and 6 c are special, and will never return those values. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 02 September 2013 c c Author: c c John Burkardt c c Parameters: c c Output, integer IUNIT, the free unit number. c implicit none integer i integer iunit logical value iunit = 0 do i = 1, 99 if ( i .ne. 5 .and. i .ne. 6 .and. i .ne. 9 ) then inquire ( unit = i, opened = value, err = 10 ) if ( .not. value ) then iunit = i return end if end if 10 continue end do return end function i4_uniform_ab ( a, b, seed ) c*********************************************************************72 c cc I4_UNIFORM_AB returns a scaled pseudorandom I4 between A and B. c c Discussion: c c An I4 is an integer value. c c The pseudorandom number should be uniformly distributed c between A and B. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 12 November 2006 c c Author: c c John Burkardt c c Reference: c c Paul Bratley, Bennett Fox, Linus Schrage, c A Guide to Simulation, c Second Edition, c Springer, 1987, c ISBN: 0387964673, c LC: QA76.9.C65.B73. c c Bennett Fox, c Algorithm 647: c Implementation and Relative Efficiency of Quasirandom c Sequence Generators, c ACM Transactions on Mathematical Software, c Volume 12, Number 4, December 1986, pages 362-376. c c Pierre L'Ecuyer, c Random Number Generation, c in Handbook of Simulation, c edited by Jerry Banks, c Wiley, 1998, c ISBN: 0471134031, c LC: T57.62.H37. c c Peter Lewis, Allen Goodman, James Miller, c A Pseudo-Random Number Generator for the System/360, c IBM Systems Journal, c Volume 8, Number 2, 1969, pages 136-143. c c Parameters: c c Input, integer A, B, the limits of the interval. c c Input/output, integer SEED, the "seed" value, which should NOT be 0. c On output, SEED has been updated. c c Output, integer I4_UNIFORM_AB, a number between A and B. c implicit none integer a integer b integer i4_huge parameter ( i4_huge = 2147483647 ) integer i4_uniform_ab integer k real r integer seed integer value if ( seed .eq. 0 ) then write ( *, '(a)' ) ' ' write ( *, '(a)' ) 'I4_UNIFORM_AB - Fatal error!' write ( *, '(a)' ) ' Input value of SEED = 0.' stop 1 end if k = seed / 127773 seed = 16807 * ( seed - k * 127773 ) - k * 2836 if ( seed .lt. 0 ) then seed = seed + i4_huge end if r = real ( seed ) * 4.656612875E-10 c c Scale R to lie between A-0.5 and B+0.5. c r = ( 1.0E+00 - r ) * ( real ( min ( a, b ) ) - 0.5E+00 ) & + r * ( real ( max ( a, b ) ) + 0.5E+00 ) c c Use rounding to convert R to an integer between A and B. c value = nint ( r ) value = max ( value, min ( a, b ) ) value = min ( value, max ( a, b ) ) i4_uniform_ab = value return end subroutine i4vec_print ( n, a, title ) c*********************************************************************72 c cc I4VEC_PRINT prints an I4VEC. c c Discussion: c c An I4VEC is a vector of integer values. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 27 November 2006 c c Author: c c John Burkardt c c Parameters: c c Input, integer N, the number of components of the vector. c c Input, integer A(N), the vector to be printed. c c Input, character*(*) TITLE, a title. c implicit none integer n integer a(n) integer i character*(*) title write ( *, '(a)' ) ' ' write ( *, '(a)' ) trim ( title ) write ( *, '(a)' ) ' ' do i = 1, n write ( *, '(2x,i8,a,1x,i12)' ) i, ':', a(i) end do return end subroutine latin_random ( dim_num, point_num, seed, x ) c*********************************************************************72 c cc LATIN_RANDOM returns points in a Latin Random square. c c Discussion: c c In each spatial dimension, there will be exactly one c point whose coordinate value lies between consecutive c values in the list: c c ( 0, 1, 2, ..., point_num ) / point_num c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 13 November 2014 c c Author: c c John Burkardt c c Parameters: c c Input, integer DIM_NUM, the spatial dimension. c c Input, integer POINT_NUM, the number of points. c c Input/output, integer SEED, a seed for the random c number generator. c c Output, double precision X(DIM_NUM,POINT_NUM), the points. c implicit none integer dim_num integer point_num integer i integer j integer perm(point_num) integer seed double precision x(dim_num,point_num) c c Pick DIM_NUM * POINT_NUM random numbers between 0 and 1. c call r8mat_uniform_01 ( dim_num, point_num, seed, x ) c c For spatial dimension I, c pick a random permutation of 1 to POINT_NUM, c force the corresponding I-th components of X to lie in the c interval ( PERM(J)-1, PERM(J) ) / POINT_NUM. c do i = 1, dim_num call perm_uniform ( point_num, seed, perm ) do j = 1, point_num x(i,j) = ( dble ( perm(j) - 1 ) + x(i,j) ) & / dble ( point_num ) end do end do return end subroutine perm_uniform ( n, seed, p ) c*********************************************************************72 c cc PERM_UNIFORM selects a random permutation of N objects. c c Discussion: c c The routine assumes the objects are labeled 1, 2, ... N. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 12 November 2014 c c Author: c c John Burkardt c c Reference: c c Albert Nijenhuis, Herbert Wilf, c Combinatorial Algorithms for Computers and Calculators, c Academic Press, 1978, c ISBN: 0-12-519260-6, c LC: QA164.N54. c c Parameters: c c Input, integer N, the number of objects to be permuted. c c Input/output, integer SEED, a seed for the random number generator. c c Output, integer P(N), a permutation of ( 1, 2, ..., N ), in standard c index form. c implicit none integer n integer i integer i4_uniform_ab integer j integer p(n) integer pk integer seed do i = 1, n p(i) = i end do do i = 1, n - 1 j = i4_uniform_ab ( i, n, seed ) pk = p(i) p(i) = p(j) p(j) = pk end do return end subroutine r8mat_transpose_print ( m, n, a, title ) c*********************************************************************72 c cc R8MAT_TRANSPOSE_PRINT prints an R8MAT, transposed. c c Discussion: c c An R8MAT is an array of R8's. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 28 April 2008 c c Author: c c John Burkardt c c Parameters: c c Input, integer M, N, the number of rows and columns. c c Input, double precision A(M,N), an M by N matrix to be printed. c c Input, character*(*) TITLE, a title. c implicit none integer m integer n double precision a(m,n) character*(*) title call r8mat_transpose_print_some ( m, n, a, 1, 1, m, n, title ) return end subroutine r8mat_transpose_print_some ( m, n, a, ilo, jlo, ihi, & jhi, title ) c*********************************************************************72 c cc R8MAT_TRANSPOSE_PRINT_SOME prints some of an R8MAT transposed. c c Discussion: c c An R8MAT is an array of R8's. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 28 April 2008 c c Author: c c John Burkardt c c Parameters: c c Input, integer M, N, the number of rows and columns. c c Input, double precision A(M,N), an M by N matrix to be printed. c c Input, integer ILO, JLO, the first row and column to print. c c Input, integer IHI, JHI, the last row and column to print. c c Input, character * ( * ) TITLE, a title. c implicit none integer incx parameter ( incx = 5 ) integer m integer n double precision a(m,n) character * ( 14 ) ctemp(incx) integer i integer i2 integer i2hi integer i2lo integer ihi integer ilo integer inc integer j integer j2hi integer j2lo integer jhi integer jlo character * ( * ) title write ( *, '(a)' ) ' ' write ( *, '(a)' ) trim ( title ) if ( m .le. 0 .or. n .le. 0 ) then write ( *, '(a)' ) ' ' write ( *, '(a)' ) ' (None)' return end if do i2lo = max ( ilo, 1 ), min ( ihi, m ), incx i2hi = i2lo + incx - 1 i2hi = min ( i2hi, m ) i2hi = min ( i2hi, ihi ) inc = i2hi + 1 - i2lo write ( *, '(a)' ) ' ' do i = i2lo, i2hi i2 = i + 1 - i2lo write ( ctemp(i2), '(i8,6x)') i end do write ( *, '('' Row'',5a14)' ) ctemp(1:inc) write ( *, '(a)' ) ' Col' j2lo = max ( jlo, 1 ) j2hi = min ( jhi, n ) do j = j2lo, j2hi do i2 = 1, inc i = i2lo - 1 + i2 write ( ctemp(i2), '(g14.6)' ) a(i,j) end do write ( *, '(2x,i8,a,5a14)' ) j, ':', ( ctemp(i), i = 1, inc ) end do end do return end subroutine r8mat_uniform_01 ( m, n, seed, r ) c*********************************************************************72 c cc R8MAT_UNIFORM_01 returns a unit pseudorandom R8MAT. c c Discussion: c c An R8MAT is an array of R8's. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 11 August 2004 c c Author: c c John Burkardt c c Reference: c c Paul Bratley, Bennett Fox, Linus Schrage, c A Guide to Simulation, c Springer Verlag, pages 201-202, 1983. c c Bennett Fox, c Algorithm 647: c Implementation and Relative Efficiency of Quasirandom c Sequence Generators, c ACM Transactions on Mathematical Software, c Volume 12, Number 4, pages 362-376, 1986. c c Peter Lewis, Allen Goodman, James Miller, c A Pseudo-Random Number Generator for the System/360, c IBM Systems Journal, c Volume 8, pages 136-143, 1969. c c Parameters: c c Input, integer M, N, the number of rows and columns in the array. c c Input/output, integer SEED, the "seed" value, which should NOT be 0. c On output, SEED has been updated. c c Output, double precision R(M,N), the array of pseudorandom values. c implicit none integer m integer n integer i integer i4_huge parameter ( i4_huge = 2147483647 ) integer j integer k integer seed double precision r(m,n) if ( seed .eq. 0 ) then write ( *, '(a)' ) ' ' write ( *, '(a)' ) 'R8MAT_UNIFORM_01 - Fatal error!' write ( *, '(a)' ) ' Input value of SEED = 0.' stop 1 end if do j = 1, n do i = 1, m k = seed / 127773 seed = 16807 * ( seed - k * 127773 ) - k * 2836 if ( seed .lt. 0 ) then seed = seed + i4_huge end if r(i,j) = dble ( seed ) * 4.656612875D-10 end do end do return end subroutine r8mat_write ( output_filename, m, n, table ) c*********************************************************************72 c cc R8MAT_WRITE writes a R8MAT file. c c Discussion: c c An R8MAT is an array of R8's. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 22 October 2009 c c Author: c c John Burkardt c c Parameters: c c Input, character * ( * ) OUTPUT_FILENAME, the output file name. c c Input, integer M, the spatial dimension. c c Input, integer N, the number of points. c c Input, double precision TABLE(M,N), the data. c implicit none integer m integer n integer j character * ( * ) output_filename integer output_unit character * ( 30 ) string double precision table(m,n) c c Open the file. c call get_unit ( output_unit ) open ( unit = output_unit, file = output_filename, & status = 'replace' ) c c Create the format string. c if ( 0 .lt. m .and. 0 .lt. n ) then write ( string, '(a1,i8,a1,i8,a1,i8,a1)' ) & '(', m, 'g', 24, '.', 16, ')' c c Write the data. c do j = 1, n write ( output_unit, string ) table(1:m,j) end do end if c c Close the file. c close ( unit = output_unit ) return end subroutine timestamp ( ) c*********************************************************************72 c cc TIMESTAMP prints out the current YMDHMS date as a timestamp. c c Licensing: c c This code is distributed under the MIT license. c c Modified: c c 12 January 2007 c c Author: c c John Burkardt c c Parameters: c c None c implicit none character * ( 8 ) ampm integer d character * ( 8 ) date integer h integer m integer mm character * ( 9 ) month(12) integer n integer s character * ( 10 ) time integer y save month data month / & 'January ', 'February ', 'March ', 'April ', & 'May ', 'June ', 'July ', 'August ', & 'September', 'October ', 'November ', 'December ' / call date_and_time ( date, time ) read ( date, '(i4,i2,i2)' ) y, m, d read ( time, '(i2,i2,i2,1x,i3)' ) h, n, s, mm if ( h .lt. 12 ) then ampm = 'AM' else if ( h .eq. 12 ) then if ( n .eq. 0 .and. s .eq. 0 ) then ampm = 'Noon' else ampm = 'PM' end if else h = h - 12 if ( h .lt. 12 ) then ampm = 'PM' else if ( h .eq. 12 ) then if ( n .eq. 0 .and. s .eq. 0 ) then ampm = 'Midnight' else ampm = 'AM' end if end if end if write ( *, & '(i2,1x,a,1x,i4,2x,i2,a1,i2.2,a1,i2.2,a1,i3.3,1x,a)' ) & d, month(m), y, h, ':', n, ':', s, '.', mm, ampm return end