Simple interpolation functions designed to be used from C. There is essentially no R support in this package, save code designed to be used by the package’s own testing. cinterpolate
is designed to be used in package code only and modification for use outside of a package is not explicitly supported.
cinterpolate
is now on CRAN and can be installed with
install.packages("cinterpolate")
Despite being only C code, this package requires a fortran compiler because it uses LAPACK and BLAS.
apt-get install gfortran
depending on your platformAfter that, install with
drat:::add("mrc-ide")
install.packages("cinterpolate")
Allocate an object to perform interpolation with. nx
and x
are the size and values of the function to be interpolated, while ny
is the number of functions to be simultaneously (but independently) interpolateed and y
is the values for these. If ny > 1
, then the values of y
are as an R matrix with nx
rows and ny
columns (the first nx
values are the first function, the second nx
are the second, and so on). The final two are booleans: fail_on_extrapolate
throws an error if extrapolation is requested, and auto_free
uses R_alloc()
rather than Calloc
allowing automatic cleanup.
With the interpolation function, an input value of xout
and given some storage yout
of length ny
, determine f(xout)
with
Once done the object must be freed with
cinterpolate_free(obj);
Somewhere in the package you must include cinterpolate.c
as
but this must be included only once or linking will fail. If you only use the interpolation in one place, you can use cinterpolate.c
rather than cinterpolate.h
. If you use interpolation in more than once place, I recommend a file src/cinterpolate.c
containing
Be sure to include in your DESCRIPTION
a line
LinkingTo: cinterpolate
cinterpolate
takes advantage of BLAS for matrix multiplication, so you may need a Makevars that includes
PKG_LIBS = ${LAPACK_LIBS} ${BLAS_LIBS} ${FLIBS}
See inst/example
for a full example of using cinterpolate
within a package
MIT + file LICENSE © Rich FitzJohn.
Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.