COUNT(3I) Last changed: 1-6-98
NAME
COUNT - Counts the number of true array elements
SYNOPSIS
COUNT ([MASK=]mask [,[DIM=]dim])
IMPLEMENTATION
UNICOS, UNICOS/mk, and IRIX systems
STANDARDS
Fortran 90
DESCRIPTION
The COUNT intrinsic function counts the number of true array elements
of argument mask along dimension dim. It accepts the following
arguments:
mask Must be of type logical. It must not be a scalar.
dim Must be a scalar. It is an integer with a value in the
range 1 <= dim <= n, where n is the rank of mask. The
corresponding actual argument must not be an optional dummy
argument. This function does a check on dim when present.
COUNT is a transformational function. The name of this intrinsic
cannot be passed as an argument.
RETURN VALUES
The result is type integer. It is a scalar result if dim is absent or
if mask has rank 1. Otherwise, the result is an array of rank n-1 and
of
shape (d , d , ..., d , d , ..., d ),
1 2 dim-1 dim+1 n
where (d , d , ..., d )
1 2 n
is the shape of mask.
The result of COUNT(mask) has a value equal to the number of TRUE
elements of mask or has the value 0 if mask is a zero-sized array.
If mask has rank 1, COUNT(mask, dim) has a value equal to that of
COUNT(mask). Otherwise, the value of
element (s , s , ..., s , s , ..., s )
1 2 dim-1 dim+1 n
of COUNT(mask, dim) is equal to
COUNT(MASK (s , s , ..., s , : , s , ..., s )).
1 2 dim-1 dim+1 n
EXAMPLES
Example 1:
* COUNT( (/ .TRUE., .FALSE., .TRUE. /) ) is 2.
* COUNT(mask) returns zero when mask is a zero-sized array.
Example 2: Assume that B is the following array:
| 1 3 5 |
| 2 4 6 |
C is the following array:
| 0 3 5 |
| 7 4 8 |
* COUNT( B .NE. C) is 3
* COUNT( B .NE. C, DIM=1) is [2, 0, 1]
* COUNT( B .NE. C, DIM=2) is [1, 2]
* COUNT( C .EQ. 1) returns zero because there are no true elements in
the mask.
Example 3: Assume that array N is as follows:
| 0 1 2 3 |
| 4 5 6 7 |
| 8 9 0 1 |
In an array section reference, you can expect the following results:
* COUNT((N(2:3,2:4).NE.0)) is 5
* COUNT((N(2:3,2:4).NE.0),DIM=1) is [2, 1, 2]
* COUNT((N(2:3,2:4).NE.0),DIM=2) is [3, 2]
SEE ALSO
Intrinsic Procedures Reference Manual, publication SR-2138, for the
printed version of this man page.
