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DIVIDE ITEMA INTO ITEMB                           ITEMD = 2
  GIVING ITEMD REMAINDER ITEMC.                   ITEMC = 6.00
  • REMAINDER phrase with rounding: 


    DIVIDE ITEMA INTO ITEMB                           ITEMD = 3
  GIVING ITEMD ROUNDED REMAINDER ITEMC.           ITEMC = 6.00
  • Effects of decimal alignment on quotient and remainder: 


    DIVIDE ITEMA INTO ITEMB                           ITEME = 2.66
  GIVING ITEME REMAINDER ITEMC.                   ITEMC =  .06
  • Effects of decimal alignment on remainder and quotient with rounding: 


    DIVIDE ITEMA INTO ITEMB                           ITEME = 2.67
  GIVING ITEME ROUNDED REMAINDER ITEMC.           ITEMC =  .06
  • The ON SIZE ERROR phrase: (IF ON SIZE ERROR occurs on an occurrence of rsult, the contents of that occurrence of rsult are unchanged.) 


    DIVIDE ITEME INTO ITEMF
   GIVING ITEMG ITEMD                             ITEMD = 15
   ON SIZE ERROR                                  ITEMG = 9
     MOVE 0 TO ITEMH.                             ITEMH = 0
  • The ON SIZE ERROR phrase:
    (IF ON SIZE ERROR occurs on remaind, the contents of remaind are unchanged.) 


    DIVIDE ITEMD INTO ITEMF
   GIVING ITEMI REMAINDER ITEMG                   ITEMI = 3
   ON SIZE ERROR                                  ITEMG = 9
     MOVE 0 TO ITEMH.                             ITEMH = 0
  • The NOT ON SIZE ERROR phrase: 


    DIVIDE ITEMD INTO ITEMF                           ITEMI = 3
   GIVING ITEMI REMAINDER ITEMC                   ITEMC = 11.00
   ON SIZE ERROR
      MOVE 0 TO ITEMH
   NOT ON SIZE ERROR
      MOVE 1 TO ITEMH.                            ITEMH = 1

    6.8.12 EVALUATE

    Function

    The EVALUATE statement selects a program action based on the evaluation of one or more conditions.

    subj-item

    is an identifier, an arithmetic or conditional expression, or a literal other than the figurative constant ZERO.

    cond

    is a conditional expression.

    obj-item

    is a literal, an identifier, or an arithmetic expression.

    stment1

    is an imperative statement.

    stment2

    is an imperative statement.

    Syntax Rules

    1. Before the first WHEN phrase: (a) subj-item and the words TRUE and FALSE are called subjects, and (b) all subjects comprise the subject set.
    2. In a WHEN phrase: (a) ANY, TRUE, FALSE, and the operands are called objects, and (b) all objects in a single WHEN phrase comprise an object set.
    3. The number of objects in the object set must equal the number of subjects in the subject set.
    4. The words THROUGH and THRU are equivalent.
    5. Two obj-items connected by a THROUGH phrase:
      • Must be of the same class
      • Combine to form one object
    6. Each object in an object set must correspond to the subject by appearing in the same ordinal position as in the subject set. For each pair:
      • The obj-item must be a valid operand for comparison to the subject.
      • TRUE, FALSE, or cond as an object must correspond only to TRUE, FALSE, or a conditional expression as the subject.
      • ANY can correspond to any type of subject.
    7. Conditional expressions can be simple or complex conditions.

    General Rules

    Evaluation Procedure

    1. The EVALUATE statement operates as if each subject and object were evaluated and assigned one of the following:
      • A numeric or nonnumeric value
      • A range of numeric or nonnumeric values
      • A truth value

      The statement assigns values according to the following rules:
        Condition Value Assigned
      a. An identifier for a subject, or for an object without the NOT or THROUGH phrases Value and class of the identifier's data item.
      b. A literal for a subject, or for an object without the NOT or THROUGH phrases Value and class of the literal.
      c. The figurative constant ZERO for an object without the NOT or THROUGH phrases Value and class of the corresponding subject.
      d. An arithmetic expression for a subject, or for an object without the NOT or THROUGH phrases Numeric value, according to the rules for evaluating arithmetic expressions.
      e. A conditional expression for a subject or a conditional expression for an object Truth value, according to the rules for evaluating conditional expressions.
      f. TRUE or FALSE as a subject or object Truth value: true for the word TRUE and false for the word FALSE.
      g. ANY for an object No further evaluation.
      h. THROUGH phrase for an object without the NOT phrase The range of values is all values that, when compared to the subject, are greater than or equal to the first obj-item and less than or equal to the second obj-item. If the first obj-item is greater than the second obj-item, there are no values in the range.
      i. Object with the NOT phrase All values not equal to the value (or range of values) that would be assigned without the NOT phrase.

    Comparison Procedure

    1. After values have been assigned to each subject and object, comparison begins. It proceeds as if the values were compared to determine if any WHEN phrase satisfies the subject set.
    2. EVALUATE compares each object in the object set of the first WHEN phrase to the subject in the same ordinal position in the subject set. The comparison is satisfied if one of the following conditions is true:
      • The items being compared are assigned numeric or nonnumeric values or a range of numeric or nonnumeric values; and the value assigned to the subject equals the value, or one of the range of values, assigned to the object, according to the rules for comparison.
      • The items being compared are assigned identical truth values.
      • The word ANY represents the object.
    3. If the comparison is satisfied for every object in an object set, the WHEN phrase containing that object set is selected.
    4. If the comparison is not satisfied for every object in an object set, the object set does not satisfy the subject set.
    5. The comparison procedure is repeated for each object set, in order of appearance, until one of these conditions occur:
      • A WHEN phrase is selected by satisfying the subject set.
      • A WHEN OTHER phrase is selected.
      • There are no more object sets.
      • The END-EVALUATE statement is reached.
      • A separator period is reached.

    Execution Procedure

    1. If a WHEN phrase is selected, execution continues with stment1.
    2. If no WHEN phrase is selected, and a WHEN OTHER phrase is present, execution continues with stment2.
    3. EVALUATE statement execution ends when one of the following conditions occurs:
      • Execution reaches the end of the selected WHEN phrase.
      • Execution reaches the end of the WHEN OTHER phrase.
      • No WHEN phrase is selected and there is no WHEN OTHER phrase.
      • Execution reaches END-EVALUATE.
      • Execution reaches a separator period.

    Additional References

    Examples

    In these examples, the results are shown as either data item values or procedure branches. However, stment can be any imperative statement, including multiple statements.

    1. One condition. 


      EVALUATE ITEMA
  WHEN "A01"            MOVE 1 TO ITEMB
  WHEN "A02" THRU "C16" MOVE 2 TO ITEMB
  WHEN "C20" THRU "L86" MOVE 3 TO ITEMB
  WHEN "R20"            ADD 1 TO R-TOT
                        GO TO  PROC-A
  WHEN OTHER            MOVE 0 TO ITEMB
  END-EVALUATE.

      Samples:
      ITEMA Result
      "A15" ITEMB = 2
      "P80" ITEMB = 0
      "F01" ITEMB = 3
      "M19" ITEMB = 0
      "A01" ITEMB = 1
      "R20" PROC-A
    2. Multiple conditions. This example shows how EVALUATE can represent a decision table.

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