PPSplineF64.bsplmatrix(tau, left_n, right_n)

Evaluate the 2d spline collocation matrix at each data site.

Parameters:

• tau (ndarray of float) – The data sites along the x axis which will instruct the pp spline.

• left_n (int) – The order of derivative to use for the left most data site and top row of the spline collocation matrix.

• right_n (int) – The order of derivative to use for the right most data site and bottom row of the spline collocation matrix.

Return type:

ndarray

Notes

The spline collocation matrix is defined as,

\[[\mathbf{B}_{k, \mathbf{t}}(\mathbf{\tau})]_{j,i} = B_{i,k,\mathbf{t}}(\tau_j)\]

where each row is a call to bsplev(), except the top and bottom rows which can be specifically adjusted to account for left_n and right_n such that, for example, the first row might be,

\[[\mathbf{B}_{k, \mathbf{t}}(\mathbf{\tau})]_{1,i} = \frac{d^n}{dx}B_{i,k,\mathbf{t}}(\tau_1)\]