naginterfaces.library.interp.dim1_monotonic_deriv¶
- naginterfaces.library.interp.dim1_monotonic_deriv(x, f, d, px)[source]¶
dim1_monotonic_deriv
evaluates a piecewise cubic Hermite interpolant and its first derivative at a set of points.For full information please refer to the NAG Library document for e01bg
https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/e01/e01bgf.html
- Parameters
- xfloat, array-like, shape
, , and must be unchanged from the previous call of
dim1_monotonic()
.- ffloat, array-like, shape
, , and must be unchanged from the previous call of
dim1_monotonic()
.- dfloat, array-like, shape
, , and must be unchanged from the previous call of
dim1_monotonic()
.- pxfloat, array-like, shape
The values of at which the interpolant is to be evaluated.
- Returns
- pffloat, ndarray, shape
contains the value of the interpolant evaluated at the point , for .
- pdfloat, ndarray, shape
contains the first derivative of the interpolant evaluated at the point , for .
- Raises
- NagValueError
- (errno )
On entry, .
Constraint: .
- (errno )
On entry, , and .
Constraint: for all .
- (errno )
On entry, .
Constraint: .
- Warns
- NagAlgorithmicWarning
- (errno )
Warning – some points in array lie outside the range . Values at these points are unreliable because computed by extrapolation.
- Notes
In the NAG Library the traditional C interface for this routine uses a different algorithmic base. Please contact NAG if you have any questions about compatibility.
dim1_monotonic_deriv
evaluates a piecewise cubic Hermite interpolant, as computed bydim1_monotonic()
, at the points , for . The first derivatives at the points are also computed. If any point lies outside the interval from to , values of the interpolant and its derivative are extrapolated from the nearest extreme cubic, and a warning is returned.If values of the interpolant only, and not of its derivative, are required,
dim1_monotonic_eval()
should be used.The function is derived from function PCHFD in Fritsch (1982).
- References
Fritsch, F N, 1982, PCHIP final specifications, Report UCID-30194, Lawrence Livermore National Laboratory