[R] legendre quadrature

[Prof. Dr. Matthias Kohl]

you could use package distrEx:

library(distrEx)
GLIntegrate(function(x) x^2, lower = -1, upper = 1, order = 50)

hth
Matthias

On 01.05.2014 09:43, pari hesabi wrote:
> Hello everybody
> I need to approximate the amount of integral by using
>   legendre quadrature. I have written a program which doesn't give me a
> logical answer; Can anybody help me and send the correct program? For
> example  the approximated amount of integral of ( x ^2)  on (-1,1) based
>   on legendre quad rule.
>
>
>
>
> integrand<-function(x) {x^2}
> rules <- legendre.quadrature.rules( 50 )
> order.rule <- rules[[50]]
> chebyshev.c.quadrature(integrand, order.rule, lower = -1, upper = 1)
>
> Thank you
> Diba 		 	   		   		 	   		
> 	[[alternative HTML version deleted]]
>
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-- 
Prof. Dr. Matthias Kohl
www.stamats.de