JKQTPlotter trunk/v5.0.0
an extensive Qt5+Qt6 Plotter framework (including a feature-richt plotter widget, a speed-optimized, but limited variant and a LaTeX equation renderer!), written fully in C/C++ and without external dependencies
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Mathematical Functions & Tools
Collaboration diagram for Mathematical Functions & Tools:

Classes

struct  JKQTPPolynomialFunctor
 a C++-functor, which evaluates a polynomial More...
 

Macros

#define JKQTP_DOUBLE_EPSILON   (std::numeric_limits<double>::epsilon())
 double-value epsilon
 
#define JKQTP_DOUBLE_NAN   (std::numeric_limits<double>::signaling_NaN())
 double-value NotANumber
 
#define JKQTP_EPSILON   JKQTP_DOUBLE_EPSILON
 double-value NotANumber
 
#define JKQTP_FLOAT_EPSILON   (std::numeric_limits<float>::epsilon())
 float-value epsilon
 
#define JKQTP_FLOAT_NAN   (std::numeric_limits<float>::signaling_NaN())
 float-value NotANumber
 
#define JKQTP_NAN   JKQTP_DOUBLE_NAN
 double-value NotANumber
 
#define JKQTPSTATISTICS_LN10   2.30258509299404568402
 $ \mbox{ln}(10)=2.30258509299404568402... $
 
#define JKQTPSTATISTICS_PI   3.14159265358979323846
 $ \pi=3.14159... $
 
#define JKQTPSTATISTICS_SQRT_2PI   2.50662827463
 $ \sqrt{2\pi}=2.50662827463 $
 

Functions

bool jkqtp_approximatelyEqual (double a, double b, double epsilon=2.0 *JKQTP_DOUBLE_EPSILON)
 compare two doubles a and b for euqality, where any difference smaller than epsilon is seen as equality
 
bool jkqtp_approximatelyEqual (float a, float b, float epsilon=2.0f *JKQTP_FLOAT_EPSILON)
 compare two floats a and b for euqality, where any difference smaller than epsilon is seen as equality
 
bool jkqtp_approximatelyUnequal (double a, double b, double epsilon=2.0 *JKQTP_DOUBLE_EPSILON)
 compare two doubles a and b for uneuqality, where any difference smaller than epsilon is seen as equality
 
bool jkqtp_approximatelyUnequal (float a, float b, float epsilon=2.0f *JKQTP_FLOAT_EPSILON)
 compare two floats a and b for uneuqality, where any difference smaller than epsilon is seen as equality
 
template<typename T >
jkqtp_bounded (T min, T v, T max)
 limits a value v to the given range min ... max
 
template<typename T , typename TIn >
jkqtp_bounded (TIn v)
 limits a value v to the range of the given type T , i.e. std::numeric_limits<T>::min() ... std::numeric_limits<T>::max()
 
template<typename T >
jkqtp_boundedRoundTo (const double &v)
 round a double v using round() and convert it to a specified type T (static_cast!). Finally the value is bounded to the range std::numeric_limits<T>::min() ... std::numeric_limits<T>::max()
 
template<typename T >
jkqtp_boundedRoundTo (T min, const double &v, T max)
 round a double v using round() and convert it to a specified type T (static_cast!). Finally the value is bounded to the range min ... max
 
template<typename T >
jkqtp_ceilTo (const double &v)
 round a double v using ceil() and convert it to a specified type T (static_cast!)
 
template<class T = int>
jkqtp_combination (T n, T k)
 Calculates a combination $ \left(\stackrel{n}{k}\right)=\frac{n!}{k!\cdot(n-k)!} $.
 
void jkqtp_combine_hash (std::size_t &seed, std::size_t hsh)
 can be used to build a hash-values from several hash-values
 
template<class T >
jkqtp_cube (T x)
 cube of a number
 
double jkqtp_distance (const QPoint &p1, const QPoint &p2)
 calculate the distance between two QPoint points
 
double jkqtp_distance (const QPointF &p1, const QPointF &p2)
 calculate the distance between two QPointF points
 
JKQTCOMMON_LIB_EXPORT void jkqtp_estimateFraction (double input, int &sign, uint64_t &intpart, uint64_t &num, uint64_t &denom, unsigned int precision=9)
 calculates numeratur integer part intpart , num and denominator denom of a fraction, representing a given floating-point number input
 
template<class T = int>
jkqtp_factorial (T n)
 Calculates a factorial $ n!=n\cdot(n-1)\cdot(n-2)\cdot...\cdot2\cdot1 $.
 
template<typename T >
jkqtp_floorTo (const double &v)
 round a double v using floor() and convert it to a specified type T (static_cast!)
 
double jkqtp_gaussdist (double x, double mu=0.0, double sigma=1.0)
 evaluates a gaussian propability density function
 
JKQTCOMMON_LIB_EXPORT uint64_t jkqtp_gcd (uint64_t a, uint64_t b)
 calculate the grwates common divisor (GCD) of a and b
 
template<class PolyItP >
std::function< double(double)> jkqtp_generatePolynomialModel (PolyItP firstP, PolyItP lastP)
 returns a C++-functor, which evaluates a polynomial
 
template<class T >
void jkqtp_hash_combine (std::size_t &seed, const T &v)
 can be used to build a hash-values from several hash-values
 
template<typename T >
jkqtp_identity (const T &v)
 returns the given value v (i.e. identity function)
 
template<typename T >
jkqtp_inverseProp (const T &v)
 returns the inversely proportional value 1/v of v
 
template<typename T >
jkqtp_inversePropSave (const T &v, const T &absMinV)
 returns the inversely proportional value 1/v of v and ensures that $ |v|\geq \mbox{absMinV} $
 
template<typename T >
jkqtp_inversePropSaveDefault (const T &v)
 returns the inversely proportional value 1/v of v and ensures that $ |v|\geq \mbox{absMinV} $, uses absMinV=std::numeric_limits<T>::epsilon()*100.0
 
double jkqtp_j0 (double x)
 j0() function (without compiler issues)
 
double jkqtp_j1 (double x)
 j1() function (without compiler issues)
 
double jkqtp_jn (int n, double x)
 jn() function (without compiler issues)
 
template<class T >
std::function< T(T)> jkqtp_makeBernstein (int n, int i)
 creates a functor that evaluates the Bernstein polynomial $ B_i^n(t):=\left(\stackrel{n}{i}\right)\cdot t^i\cdot(1-t)^{n-1},\ \ \ \ 0\leq i\leq n $
 
template<class PolyItP >
double jkqtp_polyEval (double x, PolyItP firstP, PolyItP lastP)
 evaluate a polynomial $ f(x)=\sum\limits_{i=0}^Pp_ix^i $ with $ p_i $ taken from the range firstP ... lastP
 
template<class PolyItP >
QString jkqtp_polynomialModel2Latex (PolyItP firstP, PolyItP lastP)
 Generates a LaTeX string for the polynomial model with the coefficients firstP ... lastP.
 
template<class T >
jkqtp_pow4 (T x)
 4-th power of a number
 
template<class T >
jkqtp_pow5 (T x)
 5-th power of a number
 
template<class T >
jkqtp_reversed (const T &l)
 returns the reversed containter l
 
template<typename T >
jkqtp_roundTo (const double &v)
 round a double v using round() and convert it to a specified type T (static_cast!)
 
double jkqtp_roundToDigits (const double &v, const int decDigits)
 round a double v using round() to a given number of decimal digits
 
template<class T >
jkqtp_sign (T x)
 calculates the sign of number x (-1 for x<0 and +1 for x>=0)
 
template<typename T >
jkqtp_sqr (const T &v)
 returns the quare of the value v, i.e. v*v
 
template<>
constexpr double jkqtp_todouble (const bool &d)
 converts a boolean to a double, is used to convert boolean to double by JKQTPDatastore
 
template<typename T >
constexpr double jkqtp_todouble (const T &d)
 converts a boolean to a double, is used to convert boolean to double by JKQTPDatastore
 
template<typename T >
jkqtp_truncTo (const double &v)
 round a double v using trunc() and convert it to a specified type T (static_cast!)
 
double jkqtp_y0 (double x)
 y0() function (without compiler issues)
 
double jkqtp_y1 (double x)
 y1() function (without compiler issues)
 
double jkqtp_yn (int n, double x)
 yn() function (without compiler issues)
 
template<typename T >
bool JKQTPIsOKFloat (T v)
 check whether the dlotaing point number is OK (i.e. non-inf, non-NAN)
 

Detailed Description

This group assembles a variety of mathematical tool functions that are used in different places.

Macro Definition Documentation

◆ JKQTP_DOUBLE_EPSILON

#define JKQTP_DOUBLE_EPSILON   (std::numeric_limits<double>::epsilon())

double-value epsilon

◆ JKQTP_DOUBLE_NAN

#define JKQTP_DOUBLE_NAN   (std::numeric_limits<double>::signaling_NaN())

double-value NotANumber

◆ JKQTP_EPSILON

#define JKQTP_EPSILON   JKQTP_DOUBLE_EPSILON

double-value NotANumber

◆ JKQTP_FLOAT_EPSILON

#define JKQTP_FLOAT_EPSILON   (std::numeric_limits<float>::epsilon())

float-value epsilon

◆ JKQTP_FLOAT_NAN

#define JKQTP_FLOAT_NAN   (std::numeric_limits<float>::signaling_NaN())

float-value NotANumber

◆ JKQTP_NAN

#define JKQTP_NAN   JKQTP_DOUBLE_NAN

double-value NotANumber

◆ JKQTPSTATISTICS_LN10

#define JKQTPSTATISTICS_LN10   2.30258509299404568402

$ \mbox{ln}(10)=2.30258509299404568402... $

◆ JKQTPSTATISTICS_PI

#define JKQTPSTATISTICS_PI   3.14159265358979323846

$ \pi=3.14159... $

◆ JKQTPSTATISTICS_SQRT_2PI

#define JKQTPSTATISTICS_SQRT_2PI   2.50662827463

$ \sqrt{2\pi}=2.50662827463 $

Function Documentation

◆ jkqtp_approximatelyEqual() [1/2]

bool jkqtp_approximatelyEqual ( double  a,
double  b,
double  epsilon = 2.0*JKQTP_DOUBLE_EPSILON 
)
inline

compare two doubles a and b for euqality, where any difference smaller than epsilon is seen as equality

◆ jkqtp_approximatelyEqual() [2/2]

bool jkqtp_approximatelyEqual ( float  a,
float  b,
float  epsilon = 2.0f*JKQTP_FLOAT_EPSILON 
)
inline

compare two floats a and b for euqality, where any difference smaller than epsilon is seen as equality

◆ jkqtp_approximatelyUnequal() [1/2]

bool jkqtp_approximatelyUnequal ( double  a,
double  b,
double  epsilon = 2.0*JKQTP_DOUBLE_EPSILON 
)
inline

compare two doubles a and b for uneuqality, where any difference smaller than epsilon is seen as equality

◆ jkqtp_approximatelyUnequal() [2/2]

bool jkqtp_approximatelyUnequal ( float  a,
float  b,
float  epsilon = 2.0f*JKQTP_FLOAT_EPSILON 
)
inline

compare two floats a and b for uneuqality, where any difference smaller than epsilon is seen as equality

◆ jkqtp_bounded() [1/2]

template<typename T >
T jkqtp_bounded ( min,
v,
max 
)
inline

limits a value v to the given range min ... max

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
minminimum output value
vthe value to round and cast
maxmaximum output value

◆ jkqtp_bounded() [2/2]

template<typename T , typename TIn >
T jkqtp_bounded ( TIn  v)
inline

limits a value v to the range of the given type T , i.e. std::numeric_limits<T>::min() ... std::numeric_limits<T>::max()

Template Parameters
Ta numeric datatype (int, double, ...) for the output
TIna numeric datatype (int, double, ...) or the input v
Parameters
vthe value to round and cast
Note
As a special feature, this function detectes whether one of T or TIn are unsigned and then cmpares against a limit of 0 instead of std::numeric_limits<T>::min() .

◆ jkqtp_boundedRoundTo() [1/2]

template<typename T >
T jkqtp_boundedRoundTo ( const double &  v)
inline

round a double v using round() and convert it to a specified type T (static_cast!). Finally the value is bounded to the range std::numeric_limits<T>::min() ... std::numeric_limits<T>::max()

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
vthe value to round and cast

this is equivalent to

jkqtp_boundedRoundTo<T>(std::numeric_limits<T>::min(), v, std::numeric_limits<T>::max())

◆ jkqtp_boundedRoundTo() [2/2]

template<typename T >
T jkqtp_boundedRoundTo ( min,
const double &  v,
max 
)
inline

round a double v using round() and convert it to a specified type T (static_cast!). Finally the value is bounded to the range min ... max

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
minminimum output value
vthe value to round and cast
maxmaximum output value

this is equivalent to

qBound(min, static_cast<T>(round(v)), max);

◆ jkqtp_ceilTo()

template<typename T >
T jkqtp_ceilTo ( const double &  v)
inline

round a double v using ceil() and convert it to a specified type T (static_cast!)

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
vthe value to ceil and cast

this is equivalent to

static_cast<T>(ceil(v));

◆ jkqtp_combination()

template<class T = int>
T jkqtp_combination ( n,
k 
)
inline

Calculates a combination $ \left(\stackrel{n}{k}\right)=\frac{n!}{k!\cdot(n-k)!} $.

◆ jkqtp_combine_hash()

void jkqtp_combine_hash ( std::size_t &  seed,
std::size_t  hsh 
)
inline

can be used to build a hash-values from several hash-values

std::size_t seed=0;
//...
// finally seed contains the combined hash
size_t qHash(const JKQTBasePlotter::textSizeKey &data, size_t)
qHash()-specialization
Definition jkqtpbaseplotter.h:2828
void jkqtp_combine_hash(std::size_t &seed, std::size_t hsh)
can be used to build a hash-values from several hash-values
Definition jkqtpmathtools.h:704

◆ jkqtp_cube()

template<class T >
T jkqtp_cube ( x)
inline

cube of a number

◆ jkqtp_distance() [1/2]

double jkqtp_distance ( const QPoint &  p1,
const QPoint &  p2 
)
inline

calculate the distance between two QPoint points

◆ jkqtp_distance() [2/2]

double jkqtp_distance ( const QPointF &  p1,
const QPointF &  p2 
)
inline

calculate the distance between two QPointF points

◆ jkqtp_estimateFraction()

JKQTCOMMON_LIB_EXPORT void jkqtp_estimateFraction ( double  input,
int &  sign,
uint64_t &  intpart,
uint64_t &  num,
uint64_t &  denom,
unsigned int  precision = 9 
)

calculates numeratur integer part intpart , num and denominator denom of a fraction, representing a given floating-point number input

◆ jkqtp_factorial()

template<class T = int>
T jkqtp_factorial ( n)
inline

Calculates a factorial $ n!=n\cdot(n-1)\cdot(n-2)\cdot...\cdot2\cdot1 $.

◆ jkqtp_floorTo()

template<typename T >
T jkqtp_floorTo ( const double &  v)
inline

round a double v using floor() and convert it to a specified type T (static_cast!)

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
vthe value to floor and cast

this is equivalent to

static_cast<T>(floor(v));

◆ jkqtp_gaussdist()

double jkqtp_gaussdist ( double  x,
double  mu = 0.0,
double  sigma = 1.0 
)
inline

evaluates a gaussian propability density function

\[ f(x,\mu, \sigma)=\frac{1}{\sqrt{2\pi\sigma^2}}\cdot\exp\left(-\frac{(x-\mu)^2}{2\sigma^2}\right) \]

◆ jkqtp_gcd()

JKQTCOMMON_LIB_EXPORT uint64_t jkqtp_gcd ( uint64_t  a,
uint64_t  b 
)

calculate the grwates common divisor (GCD) of a and b

◆ jkqtp_generatePolynomialModel()

template<class PolyItP >
std::function< double(double)> jkqtp_generatePolynomialModel ( PolyItP  firstP,
PolyItP  lastP 
)
inline

returns a C++-functor, which evaluates a polynomial

Template Parameters
PolyItPiterator for the polynomial coefficients
Parameters
firstPpoints to the first polynomial coefficient $ p_1 $ (i.e. the offset with $ x^0 $ )
lastPpoints behind the last polynomial coefficient $ p_P $

◆ jkqtp_hash_combine()

template<class T >
void jkqtp_hash_combine ( std::size_t &  seed,
const T &  v 
)
inline

can be used to build a hash-values from several hash-values

std::size_t seed=0;
jkqtp_hash_combine(seed, valA);
jkqtp_hash_combine(seed, valB);
//...
// finally seed contains the combined hash
void jkqtp_hash_combine(std::size_t &seed, const T &v)
can be used to build a hash-values from several hash-values
Definition jkqtpmathtools.h:686

◆ jkqtp_identity()

template<typename T >
T jkqtp_identity ( const T &  v)
inline

returns the given value v (i.e. identity function)

◆ jkqtp_inverseProp()

template<typename T >
T jkqtp_inverseProp ( const T &  v)
inline

returns the inversely proportional value 1/v of v

◆ jkqtp_inversePropSave()

template<typename T >
T jkqtp_inversePropSave ( const T &  v,
const T &  absMinV 
)
inline

returns the inversely proportional value 1/v of v and ensures that $ |v|\geq \mbox{absMinV} $

◆ jkqtp_inversePropSaveDefault()

template<typename T >
T jkqtp_inversePropSaveDefault ( const T &  v)
inline

returns the inversely proportional value 1/v of v and ensures that $ |v|\geq \mbox{absMinV} $, uses absMinV=std::numeric_limits<T>::epsilon()*100.0

◆ jkqtp_j0()

double jkqtp_j0 ( double  x)
inline

j0() function (without compiler issues)

◆ jkqtp_j1()

double jkqtp_j1 ( double  x)
inline

j1() function (without compiler issues)

◆ jkqtp_jn()

double jkqtp_jn ( int  n,
double  x 
)
inline

jn() function (without compiler issues)

◆ jkqtp_makeBernstein()

template<class T >
std::function< T(T)> jkqtp_makeBernstein ( int  n,
int  i 
)

creates a functor that evaluates the Bernstein polynomial $ B_i^n(t):=\left(\stackrel{n}{i}\right)\cdot t^i\cdot(1-t)^{n-1},\ \ \ \ 0\leq i\leq n $

◆ jkqtp_polyEval()

template<class PolyItP >
double jkqtp_polyEval ( double  x,
PolyItP  firstP,
PolyItP  lastP 
)
inline

evaluate a polynomial $ f(x)=\sum\limits_{i=0}^Pp_ix^i $ with $ p_i $ taken from the range firstP ... lastP

Template Parameters
PolyItPiterator for the polynomial coefficients
Parameters
xwhere to evaluate
firstPpoints to the first polynomial coefficient $ p_1 $ (i.e. the offset with $ x^0 $ )
lastPpoints behind the last polynomial coefficient $ p_P $
Returns
value of polynomial $ f(x)=\sum\limits_{i=0}^Pp_ix^i $ at location x

◆ jkqtp_polynomialModel2Latex()

template<class PolyItP >
QString jkqtp_polynomialModel2Latex ( PolyItP  firstP,
PolyItP  lastP 
)

Generates a LaTeX string for the polynomial model with the coefficients firstP ... lastP.

Template Parameters
PolyItPiterator for the polynomial coefficients
Parameters
firstPpoints to the first polynomial coefficient $ p_1 $ (i.e. the offset with $ x^0 $ )
lastPpoints behind the last polynomial coefficient $ p_P $

◆ jkqtp_pow4()

template<class T >
T jkqtp_pow4 ( x)
inline

4-th power of a number

◆ jkqtp_pow5()

template<class T >
T jkqtp_pow5 ( x)
inline

5-th power of a number

◆ jkqtp_reversed()

template<class T >
T jkqtp_reversed ( const T &  l)
inline

returns the reversed containter l

◆ jkqtp_roundTo()

template<typename T >
T jkqtp_roundTo ( const double &  v)
inline

round a double v using round() and convert it to a specified type T (static_cast!)

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
vthe value to round and cast

this is equivalent to

static_cast<T>(round(v));

◆ jkqtp_roundToDigits()

double jkqtp_roundToDigits ( const double &  v,
const int  decDigits 
)
inline

round a double v using round() to a given number of decimal digits

Parameters
vthe value to round and cast
decDigitsnumber of decimal digits, i.e. precision of the result

this is equivalent to

round(v * pow(10.0,(double)decDigits))/pow(10.0,(double)decDigits);

◆ jkqtp_sign()

template<class T >
T jkqtp_sign ( x)
inline

calculates the sign of number x (-1 for x<0 and +1 for x>=0)

◆ jkqtp_sqr()

template<typename T >
T jkqtp_sqr ( const T &  v)
inline

returns the quare of the value v, i.e. v*v

◆ jkqtp_todouble() [1/2]

template<>
constexpr double jkqtp_todouble ( const bool &  d)
inlineconstexpr

converts a boolean to a double, is used to convert boolean to double by JKQTPDatastore

Specialisation of the generic template jkqtp_todouble() with (true -> 1.0, false -> 0.0)

◆ jkqtp_todouble() [2/2]

template<typename T >
constexpr double jkqtp_todouble ( const T &  d)
inlineconstexpr

converts a boolean to a double, is used to convert boolean to double by JKQTPDatastore

This function uses static_cast<double>() by default, but certain specializations (e.g. for bool) are readily available.

Here is the caller graph for this function:

◆ jkqtp_truncTo()

template<typename T >
T jkqtp_truncTo ( const double &  v)
inline

round a double v using trunc() and convert it to a specified type T (static_cast!)

Template Parameters
Ta numeric datatype (int, double, ...)
Parameters
vthe value to trunc and cast

this is equivalent to

static_cast<T>(trunc(v));

◆ jkqtp_y0()

double jkqtp_y0 ( double  x)
inline

y0() function (without compiler issues)

◆ jkqtp_y1()

double jkqtp_y1 ( double  x)
inline

y1() function (without compiler issues)

◆ jkqtp_yn()

double jkqtp_yn ( int  n,
double  x 
)
inline

yn() function (without compiler issues)

◆ JKQTPIsOKFloat()

template<typename T >
bool JKQTPIsOKFloat ( v)
inline

check whether the dlotaing point number is OK (i.e. non-inf, non-NAN)