C:/Musimathics_local/Musimat/MusimatTutorial/B0123.cpp

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#include "MusimatTutorial.h"
MusimatTutorialSection(B0123) {
Print("*** B.1.23 Type Conversion ***");
/*****************************************************************************

B.1.23 Type Conversion

We can explicitly convert Integer expressions to Real, and vice versa. For example:
*****************************************************************************/

Real a = 10.0/3.0;
Print(a);

/*****************************************************************************
 prints 3.333 . . . , and
*****************************************************************************/

Integer b = Integer(a);                                                                 // convert a to Integer
Print(b);

/*****************************************************************************
prints 3.

When assigning a to b, the Real value a is converted to an Integer by truncating (discarding) 
the fractional part of a (that is, by discarding 0.333…), and the integer residue (3) is assigned to 
b. If we then write
*****************************************************************************/

Real c =  Real(b); 

/*****************************************************************************
the integer value of b (which is 3) is converted to the equivalent Real value (3.0), which is stored 
in Real variable c.

Converting from Real to Integer, we have some choices. For example, if
*****************************************************************************/

Real p = 10.0/3.0;   // Real variable a is set to 3.333 . . .

/*****************************************************************************
then
*****************************************************************************/

Real d = Floor(p); // d is set to 3.0

/*****************************************************************************
sets d to 3.0. The built-in Floor() function returns the largest integer less than its Real argu-
ment. The statement
*****************************************************************************/

Real x = Ceiling(p);

/*****************************************************************************
sets x to 4 because the built-in Ceiling() function returns the smallest integer greater than its 
argument.

We can round a Real to the nearest whole number as follows:
*****************************************************************************/

Real r = Floor(p + 0.5);                                                        // round c to the nearest whole number

/*****************************************************************************
If a = 2.4, then Floor(a + 0.5) returns 2.0. But if a = 2.5, Floor(a + 0.5) returns 
3.0. Floor(a + 0.5) returns 2.0 for any value a in the range 2.0 to 2.499... and returns 
3.0 for any value a in the range 2.5 to 2.999.... But we don’t have to do rounding ourselves, 
Musimat has a built-in function:
*****************************************************************************/

Print(Round(2.49999));                                                  // prints 2.0

}}

/* $Revision: 1.4 $ $Date: 2006/09/12 17:38:00 $ $Author: dgl $ $Name:  $ $Id: _b0123_8cpp-source.html,v 1.4 2006/09/12 17:38:00 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

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