C:/Musimathics_local/Musimat/MusimatTutorial/B0116.cpp

Go to the documentation of this file.

#include "MusimatTutorial.h"
MusimatTutorialSection(B0116) {
Print("*** B.1.16 Conditional Statements ***");
/*****************************************************************************

B.1.16 Conditional Statements

A mathematical notation for determining the sign of a number is

                | x < 0, a
        y = |
                | x >= 0, b


which sets y to a if x is negative; otherwise it sets y to b. Such relational expressions are called 
predicates. Musimat accomplishes the same thing like this:
*****************************************************************************/

Real a = 1;
Real b = 2;
Real y = 5;

If (y < 0) 
  y = a;
Else 
  y = b;

/*****************************************************************************
In this example, y receives the value of a if y is less than 0; otherwise y receives the value of b. 
The Else part of this construction is optional. So for example,
*****************************************************************************/

If (a < b)
        Print(a);

/*****************************************************************************
prints a only if it is less than b. If and Else can be combined to allow chains of predicates:
*****************************************************************************/
Real r = -1.0;

If (a < 0)         // is x negative?
  y = a;
Else If (a == 0)   // it’s not negative, but is it zero?
  y = b;
Else               // neither negative nor zero, x must be positive
  y = r;

}}

/* $Revision: 1.4 $ $Date: 2006/09/12 17:37:59 $ $Author: dgl $ $Name:  $ $Id: _b0116_8cpp-source.html,v 1.4 2006/09/12 17:37:59 dgl Exp $ */
// The Musimat Tutorial © 2006 Gareth Loy
// Derived from Chapter 9 and Appendix B of "Musimathics Vol. 1" © 2006 Gareth Loy 
// and published exclusively by The MIT Press.
// This program is released WITHOUT ANY WARRANTY; without even the implied 
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
// For information on usage and redistribution, and for a DISCLAIMER OF ALL
// WARRANTIES, see the file, "LICENSE.txt," in this distribution.
// "Musimathics" is available here:     http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=10916
// Gareth Loy's Musimathics website:    http://www.musimathics.com/
// The Musimat website:                 http://www.musimat.com/
// This program is released under the terms of the GNU General Public License
// available here:                      http://www.gnu.org/licenses/gpl.txt

---