Converting a string to an integer in Fortran 90

Question

I know that IACHAR(s) returns the code for the ASCII character in the first character position of the string s, but I need to convert the entire string to an integer. I also have a few number of strings (around 30 strings, each consists of at most 20 characters). Is there any way to convert each one of them to a unique integer in Fortran 90?

Solution

You can read a string into an integer variable:

module str2int_mod
contains 

  elemental subroutine str2int(str,int,stat)
    implicit none
    ! Arguments
    character(len=*),intent(in) :: str
    integer,intent(out)         :: int
    integer,intent(out)         :: stat

    read(str,*,iostat=stat)  int
  end subroutine str2int

end module

program test
  use str2int_mod
  character(len=20) :: str(3)
  integer           :: int(3), stat(3)

  str(1) = '123' ! Valid integer
  str(2) = '-1'  ! Also valid
  str(3) = 'one' ! invalid

  call str2int(str,int,stat)

  do i=1,3
    if ( stat(i) == 0 ) then
      print *,i,int(i)
    else
      print *,'Conversion of string ',i,' failed!'
    endif
  enddo
end program

Comments

[Admin]

read(str,*,iostat=stat) int <- this is the important part of the answer for others like me searching for the same thing. Thanks Alex. Here's some other examples: eng-tips.com/viewthread.cfm?qid=4337 & vikas-ke-funde.blogspot.com/2010/06/…

[Vladimir F Героям слава]

You should disclose that you are an author of the said library. Also, an example of a call of the conversion procedure would be more valuable than just this product advertisment.