C Library Functions - swap_any (3)
NAME
swap_any(3f) - [M_sort] subroutine swaps two variables of like type (LICENSE:PD)
CONTENTS
Synopsis
Description
Examples
SYNOPSIS
subroutine swap_any(X,Y)
DESCRIPTION
Generic subroutine swap_any(GEN1,GEN2) swaps any two variables of like type.On output, the values of X and Y have been interchanged. Swapping is commonly required in procedures that sort data.
DO NOT CURRENTLY USE WITH ANYTHING BUT SCALAR VALUES.
EXAMPLES
Example program:
program demo_swap_any use M_sort, only : swap_any integer :: iarray(2)=[10,20] real :: rarray(2)=[11.11,22.22] doubleprecision :: darray(2)=[1234.56789d0,9876.54321d0] complex :: carray(2)=[(1234,56789),(9876,54321)] logical :: larray(2)=[.true.,.false.] character(len=16) :: string(2)=["First string ","The other string"]Expected Results:integer :: one(13)=1 integer :: two(13)=2
integer :: one2(3,3)=1 integer :: two2(3,3)=2
print *, "integers before swap_any ", iarray call swap_any (iarray(1), iarray(2)) print *, "integers after swap_any ", iarray
print *, "reals before swap_any ", rarray call swap_any (rarray(1), rarray(2)) print *, "reals after swap_any ", rarray
print *, "doubles before swap_any ", darray call swap_any (darray(1), darray(2)) print *, "doubles after swap_any ", darray
print *, "complexes before swap_any ", carray call swap_any (carray(1), carray(2)) print *, "complexes after swap_any ", carray
print *, "logicals before swap_any ", larray call swap_any (larray(1), larray(2)) print *, "logicals after swap_any ", larray
print *, "strings before swap_any ", string call swap_any (string(1), string(2)) print *, "strings after swap_any ", string
write(*,*)’swap_any two vectors’ write(*,’("one before: ",*(i0,:","))’) one write(*,’("two before: ",*(i0,:","))’) two call swap_any(one,two) write(*,’("one after: ",*(i0,:","))’) one write(*,’("two after: ",*(i0,:","))’) two
write(*,*)’given these arrays initially each time ’ one2=1 two2=2 call printarrays()
write(*,*)’GETS THIS WRONG’ write(*,*)’swap_any two rows’ one2=1 two2=2 call swap_any(one2(2,:),two2(3,:)) call printarrays()
write(*,*)’GETS THIS WRONG’ write(*,*)’swap_any two columns’ one2=1 two2=2 call swap_any(one2(:,2),two2(:,2)) call printarrays()
write(*,*)’CANNOT DO MULTI-DIMENSIONAL ARRAYS YET’ write(*,*)’swap_any two arrays with same number of elements’ one2=1 two2=2 !call swap_any(one2,two2) !call printarrays()
contains subroutine printarrays() integer :: i do i=1,size(one2(1,:)) write(*,’(*(i0,:","))’) one2(i,:) enddo write(*,*) do i=1,size(two2(1,:)) write(*,’(*(i0,:","))’) two2(i,:) enddo end subroutine printarrays
end program demo_swap_any
> integers before swap_any 10 20 > integers after swap_any 20 10 > reals before swap_any 11.1099997 22.2199993 > reals after swap_any 22.2199993 11.1099997 > doubles before swap_any 1234.5678900000000 9876.5432099999998 > doubles after swap_any 9876.5432099999998 1234.5678900000000 > complexes before swap_any (1234.00000,56789.0000) (9876.00000,54321.0000) > complexes after swap_any (9876.00000,54321.0000) (1234.00000,56789.0000) > logicals before swap_any T F > logicals after swap_any F T > strings before swap_any First string The other string > strings after swap_any The other stringFirst string > swap_any two vectors >one before: 1,1,1,1,1,1,1,1,1,1,1,1,1 >two before: 2,2,2,2,2,2,2,2,2,2,2,2,2 >one after: 2,2,2,2,2,2,2,2,2,2,2,2,2 >two after: 1,1,1,1,1,1,1,1,1,1,1,1,1 > given these arrays initially each time >1,1,1 >1,1,1 >1,1,1 > >2,2,2 >2,2,2 >2,2,2 > swap_any two rows >1,1,1 >2,2,2 >1,1,1 > >2,2,2 >2,2,2 >1,1,1 > swap_any two columns >1,2,1 >1,2,1 >1,2,1 > >2,1,2 >2,1,2 >2,1,2 > swap_any two arrays with same number of elements >2,2,2 >2,2,2 >2,2,2 > >1,1,1 >1,1,1 >1,1,1
| Nemo Release 3.1 | swap_any (3) | February 23, 2025 |
