You are using the new UI (Beta).Return to the original UI

This page has been automatically translated by machine translation. Please note that translations may not be entirely accurate.

keisanHigh-precision calculations for everyday life and work

Gaussian Integration Methods (Select Integration Method)

Manage Bookmarks
Calculates the integral over the interval (a, b) using various Gaussian quadrature methods.
(Gauss–Legendre integral, first-kind Chebyshev integral, second-kind Chebyshev integral, Laguerre integral, Hermite integral, Jacobi integral, Lobatto integral, Kronrod integral)
\(\normalsize Gauss-Legendre\ quadrature\\{\large\int_{\small -1}^{\small 1}}f(x)dx\simeq{\large\displaystyle \sum_{\small i=1}^{n}}w_{i}f(x_i)\\{\large\int_a^{b}}f(x)dx\simeq{\large\frac{b-a}{2}\displaystyle \sum_{\small i=1}^{n}}w_{i}f({\large\frac{b-a}{2}}x_i+{\large\frac{b+a}{2}})\\\)
Integration Methods
Partition n
n=2,3,4,..,100
a
,
b
    f(x)
    f(x)
\(\normalsize Gaussian\ quadrature\\ \hspace{30px} {\large\int_{\small a}^{\small b}}w(x)f(x)dx\simeq{\large\displaystyle \sum_{\small i=1}^{n}}w_{i}f(x_i)\\ \hspace{20px} Quadrature \hspace{30px} interval \hspace{10px} w(x) \hspace{30px} polynomials\\ (1)\ Legendre \hspace{50px} [-1,\ 1] \hspace{25px} 1 \hspace{90px} P_n(x)\\ (2)\ Chebyshev\ 1st \hspace{5px} (-1,\ 1) \hspace{10px} {\large\frac{1}{\sqrt{1-x^2}}} \hspace{70px} T_n(x) \\ (3)\ Chebyshev\ 2nd \hspace{5px} [-1,\ 1] \hspace{10px} \sqrt{1-x^2} \hspace{65px} U_n(x) \\ (4)\ Laguerre \hspace{50px} [0,\infty) \hspace{20px} x^{\alpha} e^{-x} \hspace{65px} L_n^\alpha (x) \\ (5)\ Hermite \hspace{50px} (-\infty,\infty) \hspace{10px} e^{-x^2} \hspace{70px} H_n (x) \\ (6)\ Jacobi \hspace{75px} (-1,\ 1) \hspace{10px} (1-x)^{\alpha}(1+x)^{\beta} \hspace{5px} J_n^{\alpha,\beta} (x) \\ (7)\ Lobatto \hspace{60px} [-1,\ 1] \hspace{25px} 1 \hspace{80px} P_{n-1}^{'} (x)\\ (8)\ Kronrod \hspace{50px} [-1,\ 1] \hspace{25px} 1 \hspace{90px} P_n(x)\\ \)

No customer feedback for this calculation yet.