Manual Reference Pages - split (3m_strings)

NAME

split(3f) - [M_strings:TOKENS] parse string into an array using specified delimiters (LICENSE:PD)

Synopsis
Description
Options
Examples
Author
License

SYNOPSIS

subroutine split(input_line,array,delimiters,order,nulls)

    character(len=*),intent(in)              :: input_line
    character(len=:),allocatable,intent(out) :: array(:)
    character(len=*),optional,intent(in)     :: delimiters
    character(len=*),optional,intent(in)     :: order
    character(len=*),optional,intent(in)     :: nulls

DESCRIPTION

SPLIT(3f) parses a string using specified delimiter characters and store tokens into an allocatable array

OPTIONS

INPUT_LINE
Input string to tokenize

ARRAY Output array of tokens

DELIMITERS
List of delimiter characters. The default delimiters are the "whitespace" characters (space, tab,new line, vertical tab, formfeed, carriage return, and null). You may specify an alternate set of delimiter characters.
Multi-character delimiters are not supported (Each character in the DELIMITERS list is considered to be a delimiter).
Quoting of delimiter characters is not supported.

ORDER SEQUENTIAL|REVERSE|RIGHT
Order of output array. By default ARRAY contains the tokens having parsed the INPUT_LINE from left to right. If ORDER=’RIGHT’ or ORDER=’REVERSE’ the parsing goes from right to left. (This can be accomplished with array syntax in modern Fortran, but was more useful pre-fortran90).

NULLS=IGNORE|RETURN|IGNOREEND
Treatment of null fields. By default adjacent delimiters in the input string do not create an empty string in the output array. if NULLS=’return’ adjacent delimiters create an empty element in the output ARRAY. If NULLS=’ignoreend’ then only trailing delimiters at the right of the string are ignored.

EXAMPLES

Sample program:

   program demo_split
   use M_strings, only: split
   implicit none
   integer                      :: i
   character(len=*),parameter   :: title=’(80("="),t1,a)’
   character(len=*),parameter   :: line=&
   ’  aBcdef   ghijklmnop qrstuvwxyz  1:|:2     333|333 a B cc    ’
   character(len=:),allocatable :: array(:) ! output array of tokens
      write(*,*)’INPUT LINE:[’//line//’]’
      !
      write(*,title)’typical call: ’
      call split(line,array)
      call printme()
      !
      write(*,title)’custom delimiters=":|" : ’
      call split(line,array,delimiters=’:|’,&
      & order=’sequential’,nulls=’ignore’)
      call printme()
      !
      write(*,title)&
      ’delimiters=":|",reverse array order and count null fields:’
      call split(line,array,delimiters=’:|’,&
      & order=’reverse’,nulls=’return’)
      call printme()
      !
      write(*,title)&
      ’default delimiters, reverse array order and return null fields:’
      call split(line,array,delimiters=’’,&
      & order=’reverse’,nulls=’return’)
      call printme()
   contains
   subroutine printme()
      write(*,’(i0," ==> ",a)’)(i,trim(array(i)),i=1,size(array))
      write(*,*)’SIZE:’,size(array)
   end subroutine printme
   end program demo_split

Results:

 > INPUT LINE:
 > [  aBcdef   ghijklmnop qrstuvwxyz  1:|:2     333|333 a B cc    ]
 > typical call: ========================================================
 > 1 ==> aBcdef
 > 2 ==> ghijklmnop
 > 3 ==> qrstuvwxyz
 > 4 ==> 1:|:2
 > 5 ==> 333|333
 > 6 ==> a
 > 7 ==> B
 > 8 ==> cc
 >  SIZE:           8
 > custom delimiters=":|" : =============================================
 > 1 ==>   aBcdef   ghijklmnop qrstuvwxyz  1
 > 2 ==> 2     333
 > 3 ==> 333 a B cc
 >  SIZE:           3
 > delimiters=":|",reverse array order and count null fields:============
 > 1 ==> 333 a B cc
 > 2 ==> 2     333
 > 3 ==>
 > 4 ==>
 > 5 ==>   aBcdef   ghijklmnop qrstuvwxyz  1
 >  SIZE:           5
 > default delimiters, reverse array order and return null fields:=======
 > 1 ==>
 > 2 ==>
 > 3 ==>
 > 4 ==> cc
 > 5 ==> B
 > 6 ==> a
 > 7 ==> 333|333
 > 8 ==>
 > 9 ==>
 > 10 ==>
 > 11 ==>
 > 12 ==> 1:|:2
 > 13 ==>
 > 14 ==> qrstuvwxyz
 > 15 ==> ghijklmnop
 > 16 ==>
 > 17 ==>
 > 18 ==> aBcdef
 > 19 ==>
 > 20 ==>
 >  SIZE:          20

AUTHOR

John S. Urban

LICENSE

Public Domain

Nemo Release 3.1

split (3m_strings)

January 10, 2025

Generated by manServer 1.08 from 14727d03-0031-4144-81e3-05b6659e8f77 using man macros.

INPUT_LINE
	Input string to tokenize
ARRAY	Output array of tokens
DELIMITERS
	List of delimiter characters. The default delimiters are the "whitespace" characters (space, tab,new line, vertical tab, formfeed, carriage return, and null). You may specify an alternate set of delimiter characters. Multi-character delimiters are not supported (Each character in the DELIMITERS list is considered to be a delimiter). Quoting of delimiter characters is not supported.
ORDER SEQUENTIAL\|REVERSE\|RIGHT
	Order of output array. By default ARRAY contains the tokens having parsed the INPUT_LINE from left to right. If ORDER=’RIGHT’ or ORDER=’REVERSE’ the parsing goes from right to left. (This can be accomplished with array syntax in modern Fortran, but was more useful pre-fortran90).
NULLS=IGNORE\|RETURN\|IGNOREEND
	Treatment of null fields. By default adjacent delimiters in the input string do not create an empty string in the output array. if NULLS=’return’ adjacent delimiters create an empty element in the output ARRAY. If NULLS=’ignoreend’ then only trailing delimiters at the right of the string are ignored.