All functions operate on arrays, for example, IALL(A) is the same as
...(IAND(IAND(IAND(A(1),A(2)),A(3)),A(4)),...)
PARITY is not bitwise and is used with LOGICAL valued expressions. PARITY(A) is
A(1).NEQV.A(2).NEQV.A(3).NEQV.A(4). ...
For example,
PARITY((/F,T,F,T,F/))
is .FALSE. whereas,
PARITY((/F,T,F,T,T/))
is .TRUE..
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