CASINO manual - Theory of Condensed Matter

• Use ‘endif’ and ‘enddo’, not ‘end if’ and ‘end do’.
• No double colons should be used in simple variable declarations, e.g.,
INTEGER ialloc
except where required, e.g.,
INTEGER,INTENT(in) :: n
• In lists of declared variables, adhere to the following order:
INTENTed dummy arguments first, order: in/out/inout
INTEGER,INTENT(in)
(INTEGER,INTENT(out) etc.)
(INTEGER,INTENT(inout) etc.)
REAL(sp),INTENT(in)
REAL(dp),INTENT(in)
COMPLEX(sp),INTENT(in)
COMPLEX(dp),INTENT(in)
LOGICAL,INTENT(in)
CHARACTER(12),INTENT(in)
TYPE(xx),INTENT(in)
followed by things which are not arguments
INTEGER
REAL(sp)
REAL(dp)
COMPLEX(sp)
COMPLEX(dp)
LOGICAL
CHARACTER(12)
TYPE
Within each class, put standard variables on the first line, followed by things with attributes
like ALLOCATABLE, PARAMETER, etc., on subsequent lines, in whatever order seems aesthetically
pleasing.
Note also the CHARACTER(12), not CHARACTER*12, which is not in the Fortran 90 standard.
• Don’t use tab characters anywhere in the code.
• All units for reading and writing are to be allocated unit numbers using the standard open units
procedure, of which you can several examples throughout the source.
• Initial letters of comments are to be in capitals. Comments are to be spelt correctly and end
with a full stop/period (if they form a complete sentence). Comments must be useful.
! This is a legitimate comment.
! this is an illegitimate comment X
! tihs one is evn more illetigimate as i cant spell XX
! allocate a XXX (useless!)
allocate(a(1))
• If you add a module USE statement anywhere, don’t forget to change the dependency list
in the Makefile. This can be done automatically by running update-makefile-tool in the
CASINO/src directory.
• Module ‘USE’ statements should be in alphabetical order, followed by ‘USE ONLY’s in alphabetical
order:
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