Determine the extent of ARRAY along a specified dimension DIM, or the total number of elements in ARRAY if DIM is absent.
Fortran 90 and later, with KIND argument Fortran 2003 and later
Inquiry function
RESULT = SIZE(ARRAY[, DIM [, KIND]]) 
| ARRAY | Shall be an array of any type. If ARRAY is a pointer it must be associated and allocatable arrays must be allocated. | 
| DIM | (Optional) shall be a scalar of type INTEGERand its value shall be in the range from 1 to n, where n equals the rank of ARRAY. | 
| KIND | (Optional) An INTEGERinitialization expression indicating the kind parameter of the result. | 
The return value is of type INTEGER and of kind KIND. If KIND is absent, the return value is of default integer kind. 
PROGRAM test_size WRITE(*,*) SIZE((/ 1, 2 /)) ! 2 END PROGRAM
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