SAVE Statement

Local objects:

• are created each time a procedure is invoked,
• are destroyed when the procedure completes,
• do not retain their values between calls.

A local variable with the SAVE attribute will retain its value and allocation status between calls. For example,

   SUBROUTINE sub1
    REAL, SAVE :: keep
    REAL       :: chuck
    REAL, ALLOCATABLE, DIMENSION(:,:), SAVE :: X
     ...  
    IF (.NOT.ALLOCATED(X)) ALLOCATE(X(20,20))

• keep and X will retain their values between calls.
• X will remain allocated between calls,
• chuck will disappear between calls,
• keep and X have static storage class.

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