# if/else trinary boolean operator

*This page is for the current JSim version 2.0. Click here for the earlier JSim 1.6 version.*

This document describes the syntax of the **if - else** boolean operator.
(MML).

Prerequisites:

- Introductory Survey of MML (required)
- Introduction to the JSim GUI (recommended)

Contents:

## if - else syntax

The **if - else** boolean operator is used only with equations that specify exact numerical relationships between variables. Arbitrary nesting of **if - else** operators is allowed.

**if - else** statements can have one of the following forms:

expr2; expr3; var, var2, var3; var = if (expr1) expr2; var2 = if (expr1) expr2 else expr3; var3 = if (expr1) expr2 else (if (expr4) expr5 else expr3);

where exprX are algebraic expression of variables, with expr1 and expr4 being of the boolean type. See Algebraic Expression Syntax for further information.

## if - else example

// if else syntax: math if_else { realDomain t; t.min=0; t.max=2*PI; t.delta=0.1; real amp = 1; real phase = 0; real u(t), v(t), w(t), x(t); u = amp*sin(t-phase); v = amp*cos(t-phase); w = if (t < PI) (u + v) else (u); x = if(t > PI) (u + v) else ( if (phase > 0) u else u-v ); }

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[This page was last modified 14Sep15, 12:37 pm.]

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