integrate.catR: Numerical integration by linear interpolation (for catR...

In catR: Generation of IRT Response Patterns under Computerized Adaptive Testing

Numerical integration by linear interpolation (for catR internal use)

Description

This command computes the integral of function f(x) by providing values of x and f(x), similarly to the integrate.xy function of the R package sfsmisc.

Usage

integrate.catR(x, y)
 

Arguments

x	numeric: a vector of x values for numerical integration.
y	numeric: a vector of numerical values corresponding to f(x) values.

Details

This function was written to compute "cheap" numerical integration by providing sequences of x values and corresponding computed values f(x). It works similarly as the integrate.xy function when use.spline=FALSE is required. It was developed internally to eventually remove dependency of catR package to package sfsmisc.

Value

The approximated integral.

Author(s)

David Magis
Department of Psychology, University of Liege, Belgium
[e-mail]

References

Maechler, M. et al. (2012). sfsmisc: Utilities from Seminar fuer Statistik ETH Zurich. R package version 1.0-23. http://CRAN.R-project.org/package=sfsmisc

See Also

KL and the integrate.xy function in package sfsmisc

Examples

 # Loading the 'tcals' parameters 
 x <- seq(from = -4, to = 4, length = 33)
 y <- exp(x)
 integrate.catR(x, y) # 54.86381

## Not run: 
 # Comparison with integrate.xy
 require(sfsmisc)
 integrate.xy(x, y, use.spline = FALSE) # 54.86381
 integrate.xy(x, y) # 54.58058
 
## End(Not run)
 

catR documentation built on June 24, 2022, 9:06 a.m.