---
name: "interp"
section: "3m"
platform: "linux"
package: "iraf"
version: "2.11.3-2"
release: "Debian 3.0 (Woody)"
platforms: ["linux"]
url: "https://new.carta.tech/interp"
---

# interp(3m)

## NAME

interp

## DESCRIPTION

subroutine interp.f

source\
   Bevington, pages 266-267.

purpose\
   interpolate between data points to evaluate a function

usage \
   call interp (x, y, npts, nterms, xin, yout)

description of parameters\
   x      - array of data points for independent variable\
   y      - array of data points for dependent variable\
   npts   - number of pairs of data points\
   nterms - number of terms in fitting polynomial\
   xin    - input value of x\
   yout   - interpolated value of y

subroutines and function subprograms required \
   none

comments\
   valid for nterms up to 10\
   value of nterms may be modified by the program