pchip
Piecewise Cubic Hermite Interpolating Polynomial (PCHIP)
Description
returns
a vector of interpolated values p
= pchip(x
,y
,xq
)p
corresponding
to the query points in xq
. The values of p
are
determined by shape-preserving piecewise cubic
interpolation of x
and y
.
Examples
Input Arguments
Output Arguments
More About
Tips
spline
constructs in almost the same waypchip
constructs . However,spline
chooses the slopes at the differently, namely to make even continuous. This difference has several effects:spline
produces a smoother result, such that is continuous.spline
produces a more accurate result if the data consists of values of a smooth function.pchip
has no overshoots and less oscillation if the data is not smooth.pchip
is less expensive to set up.The two are equally expensive to evaluate.
References
[1] Fritsch, F. N. and R. E. Carlson. "Monotone Piecewise Cubic Interpolation." SIAM Journal on Numerical Analysis. Vol. 17, 1980, pp.238–246.
[2] Kahaner, David, Cleve Moler, Stephen Nash. Numerical Methods and Software. Upper Saddle River, NJ: Prentice Hall, 1988.
Extended Capabilities
Version History
Introduced before R2006a