parse string on delimiter characters and store tokens into an allocatable array given a line of structure ” par1 par2 par3 … parn ” store each par(n) into a separate variable in array.
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| character(len=*), | intent(in) | :: | input_line |
input string to tokenize |
||
| character(len=:), | intent(out), | allocatable | :: | array(:) |
output array of tokens |
|
| character(len=*), | intent(in), | optional | :: | delimiters |
list of delimiter characters |
|
| character(len=*), | intent(in), | optional | :: | order |
order of output array sequential|[reverse|right] |
|
| character(len=*), | intent(in), | optional | :: | nulls |
return strings composed of delimiters or not ignore|return|ignoreend |
subroutine split(input_line,array,delimiters,order,nulls)
!! given a line of structure " par1 par2 par3 ... parn " store each par(n) into a separate variable in array.
!!
!! * by default adjacent delimiters in the input string do not create an empty string in the output array
!! * no quoting of delimiters is supported
character(len=*),intent(in) :: input_line !! input string to tokenize
character(len=*),optional,intent(in) :: delimiters !! list of delimiter characters
character(len=*),optional,intent(in) :: order !! order of output array sequential|[reverse|right]
character(len=*),optional,intent(in) :: nulls !! return strings composed of delimiters or not ignore|return|ignoreend
character(len=:),allocatable,intent(out) :: array(:) !! output array of tokens
integer :: n ! max number of strings INPUT_LINE could split into if all delimiter
integer,allocatable :: ibegin(:) ! positions in input string where tokens start
integer,allocatable :: iterm(:) ! positions in input string where tokens end
character(len=:),allocatable :: dlim ! string containing delimiter characters
character(len=:),allocatable :: ordr ! string containing order keyword
character(len=:),allocatable :: nlls ! string containing nulls keyword
integer :: ii,iiii ! loop parameters used to control print order
integer :: icount ! number of tokens found
integer :: ilen ! length of input string with trailing spaces trimmed
integer :: i10,i20,i30 ! loop counters
integer :: icol ! pointer into input string as it is being parsed
integer :: idlim ! number of delimiter characters
integer :: ifound ! where next delimiter character is found in remaining input string data
integer :: inotnull ! count strings not composed of delimiters
integer :: ireturn ! number of tokens returned
integer :: imax ! length of longest token
! decide on value for optional DELIMITERS parameter
if (present(delimiters)) then ! optional delimiter list was present
if(delimiters/='')then ! if DELIMITERS was specified and not null use it
dlim=delimiters
else ! DELIMITERS was specified on call as empty string
dlim=' '//char(9)//char(10)//char(11)//char(12)//char(13)//char(0) ! use default delimiter when not specified
endif
else ! no delimiter value was specified
dlim=' '//char(9)//char(10)//char(11)//char(12)//char(13)//char(0) ! use default delimiter when not specified
endif
idlim=len(dlim) ! dlim a lot of blanks on some machines if dlim is a big string
if(present(order))then; ordr=lower(adjustl(order)); else; ordr='sequential'; endif ! decide on value for optional ORDER parameter
if(present(nulls))then; nlls=lower(adjustl(nulls)); else; nlls='ignore' ; endif ! optional parameter
n=len(input_line)+1 ! max number of strings INPUT_LINE could split into if all delimiter
allocate(ibegin(n)) ! allocate enough space to hold starting location of tokens if string all tokens
allocate(iterm(n)) ! allocate enough space to hold ending location of tokens if string all tokens
ibegin(:)=1
iterm(:)=1
ilen=len(input_line) ! ILEN is the column position of the last non-blank character
icount=0 ! how many tokens found
inotnull=0 ! how many tokens found not composed of delimiters
imax=0 ! length of longest token found
select case (ilen)
case (0) ! command was totally blank
case default ! there is at least one non-delimiter in INPUT_LINE if get here
icol=1 ! initialize pointer into input line
INFINITE: do i30=1,ilen,1 ! store into each array element
ibegin(i30)=icol ! assume start new token on the character
if(index(dlim(1:idlim),input_line(icol:icol))==0)then ! if current character is not a delimiter
iterm(i30)=ilen ! initially assume no more tokens
do i10=1,idlim ! search for next delimiter
ifound=index(input_line(ibegin(i30):ilen),dlim(i10:i10))
IF(ifound>0)then
iterm(i30)=min(iterm(i30),ifound+ibegin(i30)-2)
endif
enddo
icol=iterm(i30)+2 ! next place to look as found end of this token
inotnull=inotnull+1 ! increment count of number of tokens not composed of delimiters
else ! character is a delimiter for a null string
iterm(i30)=icol-1 ! record assumed end of string. Will be less than beginning
icol=icol+1 ! advance pointer into input string
endif
imax=max(imax,iterm(i30)-ibegin(i30)+1)
icount=i30 ! increment count of number of tokens found
if(icol>ilen)then ! no text left
exit INFINITE
endif
enddo INFINITE
end select
select case (trim(adjustl(nlls)))
case ('ignore','','ignoreend')
ireturn=inotnull
case default
ireturn=icount
end select
allocate(character(len=imax) :: array(ireturn)) ! allocate the array to return
!allocate(array(ireturn)) ! allocate the array to turn
select case (trim(adjustl(ordr))) ! decide which order to store tokens
case ('reverse','right') ; ii=ireturn ; iiii=-1 ! last to first
case default ; ii=1 ; iiii=1 ! first to last
end select
do i20=1,icount ! fill the array with the tokens that were found
if(iterm(i20)<ibegin(i20))then
select case (trim(adjustl(nlls)))
case ('ignore','','ignoreend')
case default
array(ii)=' '
ii=ii+iiii
end select
else
array(ii)=input_line(ibegin(i20):iterm(i20))
ii=ii+iiii
endif
enddo
end subroutine split