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 —  Statements  —

SUBTRACT

This document covers the following topics:

Related Statements: ADD | COMPRESS | COMPUTE | DIVIDE | EXAMINE | MOVE | MOVE ALL | MULTIPLY | RESET | SEPARATE

Belongs to Function Group: Arithmetic and Data Movement Operations


Function

The SUBTRACT statement is used to subtract the values of two or more operands.

If a database field is used as the result field, the SUBTRACT operation only results in an update to the internal value that is used within the program. The value for the field in the database remains unchanged.

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Syntax 1 - SUBTRACT Statement without GIVING Clause

SUBTRACT [ROUNDED] operand1   FROM operand2

Operand Definition Table:

Operand Possible Structure Possible Formats Referencing Permitted Dynamic Definition
operand1 C S A   N   N P I F   D T         yes no
operand2   S A   M   N P I F   D T         yes no

Syntax Element Description:

Syntax Element Description

operand1
FROM operand2

Operands:

operand1 is the minuend, operand2 is the subtrahend, hence the statement is equivalent to:

<oper2> := <oper2> - <oper1>

As for the formats of the operands, see also Rules for Arithmetic Assignments, Performance Considerations for Mixed Formats in the Programming Guide.

ROUNDED
ROUNDED Option:

If you specify the keyword ROUNDED, the result will be rounded.

For information on rounding, see Rules for Arithmetic Assignment, Field Truncation and Field Rounding in the Programming Guide.

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Syntax 2 - SUBTRACT Statement with GIVING Clause

SUBTRACT [ROUNDED] operand1   FROM operand2 GIVING operand3

Operand Definition Table:

Operand Possible Structure Possible Formats Referencing Permitted Dynamic Definition
operand1 C S A   N     N P I F   D T         yes no
operand2 C S A   N     N P I F   D T         yes no
operand3   S A   M A U N P I F B* D T         yes yes

* Format B of operand3 may be used only with a length of less than or equal to 4.

Syntax Element Description:

Syntax Element Description
GIVING
GIVING Clause:

When the GIVING clause is used, operand2 will not be modified, and the result will be stored in operand3.

operand1
FROM operand2
GIVING operand3

Operands:

operand2 is the minuend, operand1 is the subtrahend, operand3 is the result field, hence the statement is equivalent to:

<oper3> := <oper2>- <oper1>

As for the formats of the operands, see also the section Performance Considerations for Mixed Formats in the Programming Guide.

ROUNDED
ROUNDED Option:

If you specify the keyword ROUNDED, the result will be rounded.

For information on rounding, see Rules for Arithmetic Assignment, Field Truncation and Field Rounding in the Programming Guide.

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Example

** Example 'SUBEX1': SUBTRACT                                           
************************************************************************
DEFINE DATA LOCAL                                                       
1 #A (P2) INIT <50>                                                     
1 #B (P2)                                                               
1 #C (P1.1) INIT <2.4>                                                  
END-DEFINE                                                              
*                                                                       
SUBTRACT 6 FROM #A                                                   
WRITE NOTITLE 'SUBTRACT 6 FROM #A              '  10X '=' #A            
*                                                                       
SUBTRACT 6 FROM 11 GIVING #A                                         
WRITE         'SUBTRACT 6 FROM 11 GIVING #A    '  10X '=' #A            
*                                                                       
SUBTRACT 3 4 FROM #A GIVING #B                                        
WRITE         'SUBTRACT 3 4 FROM #A GIVING #B  '  10X '=' #A '=' #B     
*                                                                       
SUBTRACT -3 -4 FROM #A GIVING #B                                      
WRITE         'SUBTRACT -3 -4 FROM #A GIVING #B'  10X '=' #A '=' #B     
*                                                           
SUBTRACT ROUNDED 2.06 FROM #C                             
WRITE         'SUBTRACT ROUNDED 2.06 FROM #C   '  10X '=' #C
*                                                           
END                                                        

Output of Program SUBEX1:

SUBTRACT 6 FROM #A                        #A:  44        
SUBTRACT 6 FROM 11 GIVING #A              #A:   5        
SUBTRACT 3 4 FROM #A GIVING #B            #A:   5 #B:  -2
SUBTRACT -3 -4 FROM #A GIVING #B          #A:   5 #B:  12
SUBTRACT ROUNDED 2.06 FROM #C             #C:  0.3      

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