search for: clenshaw

> > I don't really know if it's a little improvement or not, so I'd like > > to have feedback from the Speex experts here. I'd have to test, but it looks right. I don't expect much improvement, but it makes the code simpler, especially for memory. Would also have to test on fixed-point and see if it works. > Maybe a new implementation should use the algorithm

Hi, After reading the paper entitled "The Computation of Line Spectral Frequencies Using Chebyshev Polynomials", P. Kabal and R. Ramachandran, IEEE Trans. on ASSP, Vol. 34, No. 6, December 1986, I rewrite the function cheb_poly_eva in lsp.c using the Clenshaw's recurrence formula, as described, for example, in Numerical Recipes in C, Second Edition (5.5 and 5.8) : static float cheb_poly_eva(spx_word32_t *coef, float x, int m, char *stack) { int k; float b0, b1, tmp; int m2=m>>1; /* Initial conditions */ b0=0; /* b_(m+1) */ b1=0; /* b_(...

Hello, Matthieu Poullet schrieb: > static float cheb_poly_eva(spx_word32_t *coef, float x, int m, char *stack) > { > int k; > float b0, b1, tmp; > int m2=m>>1; > > /* Initial conditions */ > b0=0; /* b_(m+1) */ > b1=0; /* b_(m+2) */ > > x*=2; > > /* Calculate the b_(k) */ > for(k=m2;k>0;k--) > { > tmp=b0;

...ck routines "dqags" and "dqagi". However, I would also like to have the routine "dqawoe" included. This routine is summarized as follows... c***keywords automatic integrator, special-purpose, c integrand with oscillatory cos or sin factor, c clenshaw-curtis method, (end point) singularities, c extrapolation, globally adaptive c***author piessens,robert,appl. math. & progr. div. - k.u.leuven c de doncker,elise,appl. math. & progr. div. - k.u.leuven c***purpose the routine calculates an approximation result to a gi...