Re: [Help-gsl] b-spline evaluation

[Rhys Ulerich]

Hi Iryna,

> I've tried to construct b-splines and evaluate them on the uniform knots. I
> become always the same error on the margins of the interval, over which the
> b-splines where constructed.

>    // construct five uniform knots {0, 1, 2, 3, 4}
>    gsl_bspline_knots_uniform(0, 4, w);

Are you mixing "knots" and "breakpoints"?  That method constructs
knots corresponding to uniform breakpoints on [0, 4].  The method name
is a bit confusing and specifying a basis differs from what you might
expect if you came from, say, Matlab.

- Rhys

P.S. The reference is at
http://www.gnu.org/software/gsl/manual/html_node/Constructing-the-knots-vector.html.