ex_caraxis: The Car Axis Mechanical Problem, Index 3 DAE

Description Usage Arguments Details Value Author(s) References Examples

Description

A rather simple multibody system, describing the behavior of a car axis on a bumpy road.

It is a differential algebraic equation of index 3

Usage

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caraxis (times = seq(0, 3, by = 0.01), yini = NULL, dyini = NULL,
         parms = list(), printmescd = TRUE, method = mebdfi,  
         atol=1e-6, rtol=1e-6,  ...)  

Arguments

yini

the initial (state) values for the DE system. If y has a name attribute, the names will be used to label the output matrix.

dyini

the initial derivatives of the state variables of the DE system.

times

time sequence for which output is wanted; the first value of times must be the initial time.

method

the solver to use; only mebdfi available for now

atol

absolute error tolerance, either a scalar or a vector, one value for each y.

rtol

relative error tolerance, either a scalar or a vector, one value for each y,

printmescd

if TRUE the mixed error significant digits computed using the reference solution at time 3 are printed

parms

list of parameters that overrule the default parameter values

...

additional arguments passed to the solver .

Details

The default parameters are: eps = 1e-2, M = 10, L = 1, L0 = 0.5, r = 0.1, w = 10, g = 1

Value

A matrix of class deSolve with up to as many rows as elements in times and as many columns as elements in yini, plus an additional column (the first) for the time value.

There will be one row for each element in times unless the solver returns with an unrecoverable error. If yini has a names attribute, it will be used to label the columns of the output value.

Author(s)

Karline Soetaert <[email protected]>

Francesca Mazzia <[email protected]>

References

http://www.dm.uniba.it/~testset

Examples

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out <- caraxis()
plot(out, lwd = 2, mfrow = c(3, 4))

# compare with reference solution
out[nrow(out),2:11]-reference("caraxis")

deTestSet documentation built on May 29, 2017, 2:56 p.m.