Data update

Task/FASTA-format/Fortran/fasta-format.f

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+! FASTA format
+! tested with Intel ifx (IFX) 2025.2.1 20250806             on Kubuntu 25.10
+!             GNU Fortran (Ubuntu 15.2.0-4ubuntu4) 15.2.0   on Kubuntu 25.10
+!             VSI Fortran x86-64 V8.6-001                   on OpenVMS x86_64 V9.2-3
+! No Non-standard features used, should compile on any fairly recent Fortran.
+! U.B., January 2026
+!==============================================================================
+program fasta
+
+  integer, parameter   :: maxlineLength=200             ! Assume no input line is longer than this.
+                                                        ! Wikipedia article on FASTA: typically no more than 80
+  character (len=maxlineLength) :: inLine               ! Line to read
+  integer :: l                                          ! Length of read line
+  logical :: first=.true.
+
+  ! going to read from a text file named "fasta.txt", located in the current working directory.
+  open(unit=10, file='fasta.txt', status='old', action='read', iostat=io_stat)
+  if (io_stat /= 0) then
+     print *, "Error opening file"
+     stop
+  end if
+
+  !-- Start the main I/O loop.
+  !-- For simplicity, handle only lines starting with ">" as these introduce new sequences.
+  !-- Any other lines are simply written to output without interpretation or checks.
+  !
+  do                                                      ! Loop ends at ERROR or EOF
+    read (10,'(A)', iostat=io_stat)   inLine              ! not Q format, so its ok for both intel and GNU
+    l = len_trim (inLine)                                 ! use this instead of Q format
+    if (io_stat < 0) exit                                 ! EOF: Normal end of this loop
+    if (io_stat > 0) then
+      print *, "Read error"                               ! ERROR: never seen this error condition
+      exit
+    end if
+    if (inLine (1:1) .eq. '>') then                       ! New sequence begins here
+      if (first) then       ! First sequence: DO not terminate previous output, there is none.
+        first = .false.
+        write (*,'(1x,A, ": ")', advance='no') inLine (:l) ! Without terminating previous line
+      else                  ! Second or later: terminate previous output line
+        write (*,'(/,1x,A, ": ")', advance='no')inLine (:l)
+      endif
+    else if (first) then
+      ! It is required that the 1st character of the very first line is a '>', anything else
+      ! would be an error here.
+      print *, 'ERROR: 1st char is not >'
+      stop
+    else
+      ! Within the sequence: Append to current line
+      write (*,'(A)', advance='no')  inLine (:l)
+    end if
+  end do
+
+  write (*,*)     ! Terminate last line
+end program fasta