FORTRAN 77 Language Reference

Logical Editing (L)

The L specifier is used for logical data items. The general form is:

 L  w

The L w edit specifier indicates that the field occupies w positions. The specified input/output list item must be of type LOGICAL. On input, the list item becomes defined with a logical datum. On output, the specified list item must be defined as a logical datum.

The input field consists of optional blanks, optionally followed by a decimal point, followed by a T for true, or F for false. The T or F can be followed by additional characters in the field. The logical constants, .TRUE. and .FALSE.,are acceptable as input. The output field consists of w-1 blanks followed by a T for true, or F for false.

Example: log1.f, logical output:

	LOGICAL A*1 /.TRUE./, B*2 /.TRUE./, C*4 /.FALSE./ 
	PRINT '( L1 / L2 / L4 )', A, B, C 

The program above displays:


Example: log2.f, logical input:

1	READ '(L8)', A 
	PRINT *, A 
	GO TO 1 

The program above accepts any of the following as valid input data:

t true T TRUE .t .t. .T .T. .TRUE. TooTrue 
f false F FALSE .f .F .F. .FALSE. Flakey