naginterfaces.library.ode.ivp_​stiff_​interp

naginterfaces.library.ode.ivp_stiff_interp(tsol, m, comm)

ivp_stiff_interp interpolates components of the solution of a system of first-order differential equations from information provided by those integrators in submodule ode using methods set up by calls to ivp_stiff_dassl(), ivp_stiff_bdf() or ivp_stiff_blend().

For full information please refer to the NAG Library document for d02mz

https://support.nag.com/numeric/nl/nagdoc_30/flhtml/d02/d02mzf.html

Parameters

tsolfloat

The point at which the first $m$ components of the solution are to be evaluated. $tsol$ should not normally be an extrapolation point. Extrapolation is permitted but not recommended.

mint

The number of components of the solution whose values are required.

commdict, communication object

Communication structure.

This argument must have been initialized by a prior call to ivp_stiff_exp_fulljac(), ivp_stiff_exp_bandjac(), ivp_stiff_exp_sparjac(), ivp_stiff_imp_fulljac(), ivp_stiff_imp_bandjac(), ivp_stiff_imp_sparjac(), ivp_stiff_exp_revcom() or ivp_stiff_imp_revcom().

Returns

solfloat, ndarray, shape $\left(m\right)$

The calculated value of the solution at $tsol$.

Raises

NagValueError

(errno $1$)

On entry, $\text{neq}=⟨value⟩$ and $\text{ldysav}=⟨value⟩$.

Constraint: $\text{neq}\le \text{ldysav}$.

(errno $1$)

On entry, $m=⟨value⟩$ and $\text{neq}=⟨value⟩$.

Constraint: $m\le \text{neq}$.

(errno $1$)

On entry, $\text{neq}=⟨value⟩$.

Constraint: $\text{neq}\ge 1$.

(errno $1$)

On entry, $m=⟨value⟩$.

Constraint: $m\ge 1$.

(errno $2$)

Either the integrator function has not been called prior to the first call of this function or the array has become corrupted.

Warns

NagAlgorithmicWarning

(errno $3$)

On entry, $tsol$ is an extrapolation point.

Notes

No equivalent traditional C interface for this routine exists in the NAG Library.

ivp_stiff_interp evaluates the first $m$ components of the solution of a system of ordinary differential equations at any point using natural polynomial interpolation based on information generated by the integrator. This information must be passed unchanged to ivp_stiff_interp. ivp_stiff_interp should not normally be used to extrapolate outside the range of values obtained from the above function.