TAL Programmer's Guide

Arithmetic Expressions

Using Expressions

5–18 096254 Tandem Computers Incorporated

The following example shows how the system makes automatic adjustments when

operands in an expression have different fpoints:

The fpoint of C is increased by 3

FIXED a;

FIXED(2) b;

FIXED (-1) c;

a := 2.015F * (b + c);

415

Data declarations

The final result is truncated by

5 places to match the fpoint of A

up 3

Effect on Hardware Indicators

Signed arithmetic operators affect the hardware indicators, as described in “Testing

Hardware Indicators” later in this section.

Unsigned Arithmetic

Operators

You can use binary unsigned arithmetic on operands with values in the range 0

through 65,535. For example, you can use unsigned arithmetic with pointers that

contain standard addresses. Table 5-12 lists unsigned arithmetic operators and the

operand types on which they can operate.

Table 5-12. Unsigned Arithmetic Operators

Operator Operation Operand Type Example

'+' Unsigned addition STRING, INT, or UNSIGNED(1–16) alpha '+' beta

'–' Unsigned subtraction STRING, INT, or UNSIGNED(1–16) alpha '–' beta

'*' Unsigned multiplication STRING, INT, or UNSIGNED(1–16) alpha '

' beta

'/' Unsigned division INT(32) or UNSIGNED (17–31)

dividend and STRING, INT, or

UNSIGNED(1–16) divisor

alpha '/' beta

'\' Unsigned modulo division

INT(32) or UNSIGNED (17–31)

dividend and STRING, INT, or

UNSIGNED(1–16) divisor

alpha '\' beta

Unsigned modulo operations return the remainder. If the quotient exceeds 16 bits, an overflow

condition occurs and the results will have unpredictable values. For example, the modulo

operation 200000D '\' 2 causes an overflow because the quotient exceeds 16 bits.