# PetscDTJacobiEvalJet
Evaluate the jet (function and derivatives) of the Jacobi polynomials basis up to a given degree. The Jacobi polynomials with indices $\alpha$ and $\beta$ are orthogonal with respect to the weighted inner product $\langle f, g \rangle = \int_{-1}^1 (1+x)^{\alpha} (1-x)^{\beta} f(x) g(x) dx$. 
## Synopsis
```
#include "petscdt.h" 
PetscErrorCode PetscDTJacobiEvalJet(PetscReal alpha, PetscReal beta, PetscInt npoints, const PetscReal points[], PetscInt degree, PetscInt k, PetscReal p[])
```

## Input Parameters

- ***alpha -*** the left exponent of the weight
- ***beta -*** the right exponetn of the weight
- ***npoints -*** the number of points to evaluate the polynomials at
- ***points -*** [npoints] array of point coordinates
- ***degree -*** the maximm degree polynomial space to evaluate, (degree + 1) will be evaluated total.
- ***k -*** the maximum derivative to evaluate in the jet, (k + 1) will be evaluated total.



## Output Parameters

- ***p -*** an array containing the evaluations of the Jacobi polynomials's jets on the points.  the size is (degree + 1) x
(k + 1) x npoints, which also describes the order of the dimensions of this three-dimensional array: the first
(slowest varying) dimension is polynomial degree; the second dimension is derivative order; the third (fastest
varying) dimension is the index of the evaluation point.





## See Also
 `PetscDTJacobiEval()`, `PetscDTPKDEvalJet()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/dt/interface/dt.c.html#PetscDTJacobiEvalJet">src/dm/dt/interface/dt.c</A>


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