gaussian quadrature

[Didier Lachieze]

(08-25-2015 09:23 AM)Antonio Wrote:  Regarding the program 1 , what I mean is that sometimes it runs and calculates the roots and coefficients and sometimes fails to execute
M2:=CAS.zeros(legendre(nr)); or
F1:=CAS.diff(legendre(nr));
does not give any error message unless it does not.

On my side every time I've tried the program 1 it has worked correctly so I can't reproduce your issue.

(08-25-2015 09:23 AM)Antonio Wrote:  Another problem is that not running the loop, and I 've been manually deactivated by assigning values ​​to the variable i, work when i = 2 or i = 3 , but not when i = 1, the error is in

M1(i,1):=2/((1-M2(i)^2)*(a0^2));
and I dont see the failure more I look.

I think this is because M1 is predefined as a matrix of reals and you're trying to assign to it an exact number when a0 is -3/2. Try with adding a dot to the first 2 to get an approximate number (or create your own matrix variable, different from the predefined ones M0-M9):

M1(i,1):=2./((1-M2(i)^2)*(a0^2));