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|
[ROUNDED ]
|
{operand1 [:]= } |
arithmetic-expression |
This document covers the following topics:
For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.
Related Statements: ADD
| COMPRESS
|
DIVIDE
|
EXAMINE
|
MOVE
|
MOVE ALL
|
MULTIPLY
|
RESET
|
SEPARATE
|
SUBTRACT
Belongs to Function Group: Arithmetic and Data Movement Operations
The COMPUTE
statement is used to perform an arithmetic or
assignment operation.
A COMPUTE
statement with multiple target operands
(operand1
) is identical to the
corresponding individual COMPUTE
statements if the source operand
(operand2
) is not an arithmetic
expression.
#TARGET1 := #TARGET2 := #SOURCE
is identical to
#TARGET1 := #SOURCE #TARGET2 := #SOURCE
Example:
DEFINE DATA LOCAL 1 #ARRAY(I4/1:3) INIT <3,0,9> 1 #INDEX(I4) 1 #RESULT(I4) END-DEFINE * #INDEX := 1 * #INDEX := /* #INDEX is 3 #RESULT := /* #RESULT is 9 #ARRAY(#INDEX) * #INDEX := 2 * #INDEX := /* #INDEX is 0 #ARRAY(3) := /* returns runtime error NAT1316 #ARRAY(#INDEX) END
If the source operand is an arithmetic expression, the expression is evaluated and its result is stored in a temporary variable. Then the temporary variable is assigned to the target operands.
#TARGET1 := #TARGET2 := #SOURCE1 + 1 is identical to #TEMP := #SOURCE1 + 1 #TARGET1 := #TEMP #TARGET2 := #TEMP
Example:
DEFINE DATA LOCAL 1 #ARRAY(I4/1:3) INIT <2, 0, 9> 1 #INDEX(I4) 1 #RESULT(I4) END-DEFINE * #INDEX := 1 * #INDEX := /* #INDEX is 3 #RESULT := /* #RESULT is 3 #ARRAY(#INDEX) + 1 * #INDEX := 2 * #INDEX := /* #INDEX is 0 #ARRAY(3) := /* returns run time error NAT1316 #ARRAY(#INDEX) END
For further information, see Rules for Arithmetic Assignment in the Programming Guide and particularly the following sections:
Data Transfer (for information on data transfer compatibility and the rules for data transfer)
Operand Definition Table:
Operand | Possible Structure | Possible Formats | Referencing Permitted | Dynamic Definition | |||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
operand1
|
S | A | M | A | U | N | P | I | F | B | D | T | L | C | G | O | yes | yes | |||
operand2
|
C | S | A | N | E | A | U | N | P | I | F | B | D | T | L | C | G | O | yes | no | |
operand3
|
C | S | N | P | I | B* | yes | no | |||||||||||||
operand4
|
C | S | N | P | I | B* | yes | no |
* If operand3
or
operand4
is a binary variable, it may
be used only with a length of less than or equal to 4.
Syntax Element Description:
Syntax Element | Description | |
---|---|---|
COMPUTE |
ASSIGN [:]=
|
Usage of Keywords:
This statement may be issued in short form by omitting the
statement keyword In structured mode, when the statement keyword
However, when the |
|
ROUNDED
|
ROUNDED Option:
If you specify the keyword For information on rounding, see Rules for Arithmetic Assignments, Field Truncation and Field Rounding in the Programming Guide. |
|
operand1 |
Result Field:
For the precision of the result, see Precision of Results of Arithmetic Operations in the Programming Guide. If If For general information on dynamic variables, see Using Dynamic and Large Variables. |
|
arithmetic-expression
|
An arithmetic expression consists of one or more constants, database fields, and user-defined variables. Natural mathematical functions (described in the System Functions documentation) may also be used as arithmetic operands. Operands used in an arithmetic expression must be defined with format N, P, I, F, D, or T. As for the formats of the operands, see also Performance Considerations for Mixed Formats in the Programming Guide. The following connecting operators may be used: |
|
Operator: | Symbol: | |
Parentheses | ( ) |
|
Exponentiation | ** |
|
Multiplication | * |
|
Division | / |
|
Addition | + |
|
Subtraction | - |
|
Each operator should be preceded and followed by at least one blank so as to avoid any conflict with a variable name that contains any of the above characters. The processing order of arithmetic operations is:
|
||
operand2 |
Source Field:
See User-Defined Constants in the Programming Guide. |
|
SUBSTRING (operand2,operand3,operand4)
|
SUBSTRING Option:
Without the substring option, the whole content of
If After the field name
( For example, to assign the 3rd to 6th position of field
#A := SUBSTRING(#B,3,4) If you omit Note: See also |
The precision (number of decimal positions) of the result of a division
in a COMPUTE
statement is determined by the precision of either
the first operand (dividend) or the first result field, whichever is
greater.
For a division of integer operands, however, the following applies: For a division of two integer constants, the precision of the result is determined by the precision of the first result field; however, if at least one of the two integer operands is a variable, the result is also of integer format (that is, without decimal positions, regardless of the precision of the result field).
** Example 'ASGEX1S': ASSIGN (structured mode) ************************************************************************ DEFINE DATA LOCAL 1 #A (N3) 1 #B (A6) 1 #C (N0.3) 1 #D (N0.5) 1 #E (N1.3) 1 #F (N5) 1 #G (A25) 1 #H (A3/1:3) END-DEFINE * ASSIGN #A = 5 WRITE NOTITLE '=' #A ASSIGN #B = 'ABC' WRITE '=' #B ASSIGN #C = .45 WRITE '=' #C ASSIGN #D = #E = -0.12345 WRITE '=' #D / '=' #E ASSIGN ROUNDED #F = 199.999 WRITE '=' #F #G := 'HELLO' WRITE '=' #G #H (1) := 'UVW' #H (3) := 'XYZ' WRITE '=' #H (1:3) * END
#A: 5 #B: ABC #C: .450 #D: -.12345 #E: -0.123 #F: 200 #G: HELLO #H: UVW XYZ
Equivalent reporting-mode example: ASGEX1R.
** Example 'CPTEX1': COMPUTE ************************************************************************ DEFINE DATA LOCAL 1 EMPLOY-VIEW VIEW OF EMPLOYEES 2 PERSONNEL-ID 2 SALARY (1:2) * 1 #A (P4) 1 #B (N3.4) 1 #C (N3.4) 1 #CUM-SALARY (P10) 1 #I (P2) END-DEFINE * COMPUTE #A = 3 * 2 + 4 / 2 - 1 WRITE NOTITLE 'COMPUTE #A = 3 * 2 + 4 / 2 - 1' 10X '=' #A * COMPUTE ROUNDED #B = 3 -4 / 2 * .89 WRITE 'COMPUTE ROUNDED #B = 3 -4 / 2 * .89' 5X '=' #B * COMPUTE #C = SQRT (#B) WRITE 'COMPUTE #C = SQRT (#B)' 18X '=' #C * LIMIT 1 READ EMPLOY-VIEW BY PERSONNEL-ID STARTING FROM '20017000' WRITE / 'CURRENT SALARY: ' 4X SALARY (1) / 'PREVIOUS SALARY:' 4X SALARY (2) FOR #I = 1 TO 2 COMPUTE #CUM-SALARY = #CUM-SALARY + SALARY (#I) END-FOR WRITE 'CUMULATIVE SALARY:' #CUM-SALARY END-READ * END
COMPUTE #A = 3 * 2 + 4 / 2 - 1 #A: 7 COMPUTE ROUNDED #B = 3 -4 / 2 * .89 #B: 1.2200 COMPUTE #C = SQRT (#B) #C: 1.1045 CURRENT SALARY: 34000 PREVIOUS SALARY: 32300 CUMULATIVE SALARY: 66300