Type: Package
Title: 'C++' Header Library for Ordinary Differential Equations
Version: 1.2
Description: A 'C++' header library for using the 'libsoda-cxx' library with R. The 'C++' header reimplements the 'lsoda' function from the 'ODEPACK' library for solving initial value problems for first order ordinary differential equations (Hindmarsh, 1982; https://computing.llnl.gov/sites/default/files/ODEPACK_pub1_u88007.pdf). The 'C++' header can be used by other R packages by linking against this package. The 'C++' functions can be called inline using 'Rcpp'. Finally, the package provides an 'ode' function to call from R.
License: MIT + file LICENSE
URL: https://github.com/mclements/lsoda
BugReports: https://github.com/mclements/lsoda/issues
Imports: Rcpp (≥ 1.0.12)
Suggests: deSolve, RcppArmadillo, RcppEigen, microbenchmark
LinkingTo: Rcpp
RoxygenNote: 7.3.2
Encoding: UTF-8
NeedsCompilation: yes
Packaged: 2025-05-11 19:20:18 UTC; marcle
Author: Mark Clements [aut, cre], Dilawar Singh [ctb], Heng Li [ctb], Peter N. Brown [ctb], George D. Byrne [ctb], Alan C. Hindmarsh [ctb], Cleve Moler [ctb], Linda R. Petzold [ctb]
Maintainer: Mark Clements <mark.clements@ki.se>
Repository: CRAN
Date/Publication: 2025-05-11 19:30:02 UTC

lsoda: 'C++' Header Library for Ordinary Differential Equations

Description

To learn more about 'libsoda-cxx' visit the [website](https://github.com/dilawar/libsoda-cxx).

Author(s)

Maintainer: Mark Clements mark.clements@ki.se

Other contributors:

See Also

Useful links:

Code to use the lsoda package inline. Not directly called by the user.

Description

Code to use the lsoda package inline. Not directly called by the user.

Usage

inlineCxxPlugin(...)

Arguments

...

arguments

Ordinary differential equation solver using lsoda

Description

Ordinary differential equation solver using lsoda

Usage

ode(y, times, func, parms, rtol = 1e-06, atol = 1e-06, ...)

Arguments

y

vector of initial state values

times

vector of times – including the start time

func

R function with signature function(t,y,parms,...) that returns a list. The first list element is a vector for dy/dt. The second list elements, if it exists, is a vector of result calculations to be retained.

parms

list or vector of parameters that are pass to func

rtol

double for the relative tolerance

atol

double for the absolute tolerance

...

other parameters that are passed to func

Value

a matrix for times in the first column and the state andd results values in the other columns.

Examples

 times = c(0,0.4*10^(0:10))
 y = c(1,0,0)
 func = function(t,y,parms,b=-0.04E0) {
     ydot = rep(0,3)
     ydot[1] = parms$a * y[2] * y[3] + b * y[1]
     ydot[3] = 3.0E7 * y[2] * y[2]
     ydot[2] = -1.0 * (ydot[1] + ydot[3])
     list(ydot, sum(y))
 }
 lsoda::ode(y, times, func, parms=list(a=1.0E4), rtol=1e-8, atol=1e-8)

Ordinary differential equation solver using lsoda (C++ code)

Description

Ordinary differential equation solver using lsoda (C++ code)

Usage

ode_cpp(y, times, func, rtol = 1e-06, atol = 1e-06)

Arguments

y

vector of initial state values

times

vector of times – including the start time

func

R function with signature function(t,y) that returns a list: the first list element is a vector for dy/dt; the second list element, if it exists, is a vector of result calculations to be retained.

rtol

double for the relative tolerance

atol

double for the absolute tolerance

Value

a matrix for times in the first column and the state andd results values in the other columns.

Examples

  times = c(0,0.4*10^(0:10))
 y = c(1,0,0)
 func = function(t,y) {
     ydot = rep(0,3)
     ydot[1] = 1.0E4 * y[2] * y[3] - .04E0 * y[1]
     ydot[3] = 3.0E7 * y[2] * y[2]
     ydot[2] = -1.0 * (ydot[1] + ydot[3])
     list(ydot, sum(y))
 }
 lsoda::ode_cpp(y,times,func, rtol=1e-8, atol=1e-8)