/sys$common/syshlp/helplib.hlb FORTRAN, Statements, IF, Block  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Executes a block of statements if the logical expression is true.
  The block of statements starts immediately following the IF
  statement.  The block of statements can be followed by optional
  ELSE IF statements (any number) and one optional ELSE statement.
  The entire block IF construct must be terminated by an END IF
  statement.  Format:

     IF (e) THEN
       block
     ELSE IF (e1) THEN
       block
     ELSE
       block
     END IF

     e,e1   Are logical expressions.

     block  Is a series of zero or more Fortran statements
            (called a statement block).

  NOTE:  No additional statement can be placed after the IF THEN
  statement in a block IF construct.  For example, the following
  statement is invalid in the block IF construct:

     IF (e) THEN I = J

  This statement is translated as the following logical IF statement:

     IF (e) THENI = J