Describes the maths functions used by application programs.

Math functions are designed for use by application programs which must be able firstly to do the desired calculation and secondly to handle error conditions arising from the calculations. Thus, the ANSI-style functions of the form

double sin(double); // typical declaration

double x=1; // argument double a; // result a=sin(x); // typical use

are not implemented by the Symbian software platform. Rather, all functions return error information explicitly.

All
functions are provided as static member functions of the
`
Math
`
class.
This is a convenient packaging mechanism. A typical math function is thus
declared like this:

class Math { public: // ... static TInt Sin(TReal &aTrg,const TReal &aSrc); // ... };

and used like this:

TReal x=1; // argument TReal a; // result TInt matherror; // error indication matherror=Math::ASin(a,x); // get result and error User::LeaveIfError(matherror); // handle error

This syntax
is unusual for those used to the ANSI library. However, the ANSI library functions
are designed for speed, and for users whose programs control the valid range
of the arguments, and can thus reasonably ensure that they are within range.
The
`
Math
`
class, however, provides direct support to expression
interpreters acting on numbers entered by users. In this context, error checking
is a vital part of the process.

In most cases, the same variable may
be used for both argument and result, i.e.,
`
Math::Sin(x,x)
`
will
work as expected, because the function has finished with the argument by the
time the result is written to.

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reserved. Unless otherwise stated, these materials are provided under the terms of the Eclipse Public License
v1.0.