std::hermite, std::hermitef, std::hermitel
double hermite( unsigned int n, double x ); float hermite( unsigned int n, float x ); long double hermite( unsigned int n, long double x ); float hermitef( unsigned int n, float x ); long double hermitel( unsigned int n, long double x ); | (1) | (since C++17) |
double hermite( unsigned int n, IntegralType x ); | (2) | (since C++17) |
double
.Parameters
n | - | the degree of the polynomial |
x | - | the argument, a value of a floating-point or integral type |
Return value
If no errors occur, value of the order-n
Hermite polynomial of x
, that is (-1)nex2
dn |
dxn |
, is returned.
Error handling
Errors may be reported as specified in math_errhandling.
- If the argument is NaN, NaN is returned and domain error is not reported
- If
n
is greater or equal than 128, the behavior is implementation-defined
Notes
Implementations that do not support C++17, but support ISO 29124:2010, provide this function if __STDCPP_MATH_SPEC_FUNCS__
is defined by the implementation to a value at least 201003L and if the user defines __STDCPP_WANT_MATH_SPEC_FUNCS__
before including any standard library headers.
Implementations that do not support ISO 29124:2010 but support TR 19768:2007 (TR1), provide this function in the header tr1/cmath
and namespace std::tr1
.
An implementation of this function is also available in boost.math.
The Hermite polynomials are the polynomial solutions of the equation u,,
-2xu,
= -2nu.
The first few are:
- hermite(0, x) = 1
- hermite(1, x) = 2x
- hermite(2, x) = 4x2
-2 - hermite(3, x) = 8x3
-12x - hermite(4, x) = 16x4
-48x2
+12
Example
#include <cmath> #include <iostream> double H3(double x) { return 8*std::pow(x,3) - 12*x; } double H4(double x) { return 16*std::pow(x,4)-48*x*x+12; } int main() { // spot-checks std::cout << std::hermite(3, 10) << '=' << H3(10) << '\n' << std::hermite(4, 10) << '=' << H4(10) << '\n'; }
Output:
7880=7880 155212=155212
See also
(C++17)(C++17)(C++17) | Laguerre polynomials (function) |
(C++17)(C++17)(C++17) | Legendre polynomials (function) |
External links
Weisstein, Eric W. ""Hermite Polynomial." From MathWorld--A Wolfram Web Resource.
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