MERGE Intrinsic

MERGE(TSOURCE,FSOURCE,MASK)

This function merges two arrays under mask control. TSOURCE, FSOURCE and MASK must all conform and the result is TSOURCE where MASK is .TRUE. and FSOURCE where it is .FALSE..

Consider,

    INTEGER, DIMENSION(2,3) :: TSOURCE, FSOURCE
    LOGICAL, DIMENSION(2,3) :: MASK
    LOGICAL, PARAMETER :: T = .TRUE.
    LOGICAL, PARAMETER :: F = .FALSE.
    TSOURCE = RESHAPE((/1,3,5,7,9,11/), (/2,3/))
    FSOURCE = RESHAPE((/0,2,4,6,8,10/), (/2,3/))
    MASK    = RESHAPE((/T,F,T,F,F,T/), (/2,3/))

Now, as

the highlighted elements are selected from the two source arrays,

and

thus