Mathematical helper functions


Functions
template<typename F>
bool	approx (F a, F b, F epsilon=1e-5)
template<typename F>
bool	abs_approx (F a, F b, F epsilon=1e-5)
template<typename I, typename F>
I	ifloor (F arg)
template<typename I, typename F>
I	nearest (F arg)
template<typename T>
T	weak_modulo (T v1, T v2)
double	fmodulo (double v1, double v2)
template<typename I>
I	imodulo (I v1, I v2)
template<typename T>
T	sign (const T &signvalue)
template<typename I>
unsigned int	isqrt (I arg)
template<typename I>
unsigned int	ilog2 (I arg)
double	safe_atan2 (double y, double x)
template<typename T>
int	interpol_left (const T *begin, int len, const T &val)
template<typename T>
int	interpol_nearest (const T *begin, int len, const T &val)

Detailed Description

Function Documentation

template<typename F>

bool approx	(	F	a,
		F	b,
		F	epsilon = `1e-5`
	)			`[inline]`

Returns true if | a-b | < epsilon * | b |, else false.

Definition at line 48 of file cxxutils.h.

template<typename F>

bool abs_approx	(	F	a,
		F	b,
		F	epsilon = `1e-5`
	)			`[inline]`

Returns true if | a-b | < epsilon, else false.

Definition at line 55 of file cxxutils.h.

template<typename I, typename F>

I ifloor ( F arg ) [inline]

Returns the largest integer which is smaller than (or equal to) arg.

Definition at line 62 of file cxxutils.h.

template<typename I, typename F>

I nearest ( F arg ) [inline]

Returns the integer which is nearest to arg.

Definition at line 68 of file cxxutils.h.

template<typename T>

T weak_modulo	(	T	v1,
		T	v2
	)			`[inline]`

Returns v1+v2 if v1<0, v1-v2 if v1>=v2, else v1.

v1 can be positive or negative; v2 must be positive.

Definition at line 76 of file cxxutils.h.

double fmodulo	(	double	v1,
		double	v2
	)			`[inline]`

Returns the remainder of the division v1/v2.

The result is non-negative. v1 can be positive or negative; v2 must be positive.

Definition at line 82 of file cxxutils.h.

template<typename I>

I imodulo	(	I	v1,
		I	v2
	)			`[inline]`

Returns the remainder of the division v1/v2.

The result is non-negative. v1 can be positive or negative; v2 must be positive.

Definition at line 91 of file cxxutils.h.

template<typename T>

T sign ( const T & signvalue ) [inline]

Returns -1 if signvalue is negative, else +1.

Definition at line 95 of file cxxutils.h.

template<typename I>

unsigned int isqrt ( I arg ) [inline]

Returns the integer n, which fulfills n*n<=arg<(n+1)*(n+1).

Definition at line 99 of file cxxutils.h.

template<typename I>

unsigned int ilog2 ( I arg ) [inline]

Returns the largest integer n that fulfills 2^n<=arg.

Definition at line 109 of file cxxutils.h.

double safe_atan2	(	double	y,
		double	x
	)			`[inline]`

Returns atan2(y,x) if x!=0 or y!=0; else returns 0.

Definition at line 121 of file cxxutils.h.

template<typename T>

int interpol_left	(	const T *	begin,
		int	len,
		const T &	val
	)			`[inline]`

Returns an index to the left of two interpolation values.

begin points to an array containing a sequence of values sorted in ascending order. The length of the array is len. If val is lower than the first element, 0 is returned. If val is higher than the last element, len-2 is returned. Else, the index of the largest element smaller than val is returned.

Definition at line 135 of file cxxutils.h.

template<typename T>

int interpol_nearest	(	const T *	begin,
		int	len,
		const T &	val
	)			`[inline]`

Returns an index to the nearest interpolation value.

begin points to an array containing a sequence of values sorted in ascending order. The length of the array is len. If val is lower than the first element, 0 is returned. If val is higher than the last element, len-1 is returned. Else, the index of the nearest element within the sequence of values is returned.

Definition at line 152 of file cxxutils.h.

Mathematical helper functions

Functions

Detailed Description

Function Documentation