De Boor's algorithm
= De Boor's algorithm
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= De Boor algorithm
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For degree $p$, knots $t_i$ and span $[t_k,t_{k+1})$, initialize $d_j^{(0)}=P_{k-p+j}$ for $0\le j\le p$. At level $r$, update $j=p,p-1,\ldots,r$ by $d_j^{(r)}=(1-\alpha_{j,r})d_{j-1}^{(r-1)}+\alpha_{j,r}d_j^{(r-1)}$, where $\alpha_{j,r}=(t-t_{k-p+j})/(t_{k+1+j-r}-t_{k-p+j})$. The point is $d_p^{(p)}$. This evaluates a <B-spline> by local affine combinations.
// Target: analysis.bigb