Mixed Type Assignment

Problems often occur with mixed-type arithmetic; the rules for type conversion are given below.

• INTEGER = REAL (or DOUBLE PRECISION)

  The RHS is evaluated, truncated (all the decimal places lopped off) then assigned to the LHS.

• REAL (or DOUBLE PRECISION) = INTEGER

  The RHS is promoted to be REAL and stored (approximately) in the LHS.

For example,

    REAL :: a = 1.1, b = 0.1
    INTEGER :: i, j, k
    i = 3.9       ! i will be 3
    j = -0.9      ! j will be 0
    k = a - b     ! k will be 1 or 0
    a = j         ! a will be about 1.0 or 0.0

Note: as a and b stored approximately, the value of k is uncertain.

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