naginterfaces.library.ode.ivp_​adams_​diag

naginterfaces.library.ode.ivp_adams_diag(neqf, comm)

ivp_adams_diag is a diagnostic function which may be called after a call to either of the integration functions ivp_adams_roots() and ivp_adams_roots_revcom().

For full information please refer to the NAG Library document for d02qx

https://www.nag.com/numeric/nl/nagdoc_29.3/flhtml/d02/d02qxf.html

Parameters

neqfint

The number of first-order ordinary differential equations solved by the integration function. It must be the same argument $neqf$ supplied to the setup function ivp_adams_setup() and the integration functions ivp_adams_roots() or ivp_adams_roots_revcom().

commdict, communication object

Communication structure.

This argument must have been initialized by prior calls to ivp_adams_setup() and one of ivp_adams_roots() or ivp_adams_roots_revcom().

Returns

ypfloat, ndarray, shape $\left(neqf\right)$

The approximate derivative of the solution component $y_i$, as supplied in $y_i$ on output from the integration function at the output value of $\text{t}$. These values are obtained by the evaluation of $y^{\prime }=f(x,y)$ except when the output value of the argument $\text{t}$ in the call to the integration function is $\text{tout}$ and $tcurr\ne \text{tout}$, in which case they are obtained by interpolation.

tcurrfloat

The value of the independent variable which the integrator has actually reached. $tcurr$ will always be at least as far as the output value of the argument $\text{t}$ (from the integration function) in the direction of integration, but may be further.

hlastfloat

The last successful step size used by the integrator.

hnextfloat

The next step size which the integration function would attempt.

odlastint

The order of the method last used (successfully) by the integration function.

odnextint

The order of the method which the integration function would attempt on the next step.

nsuccint

The number of steps attempted by the integration function that have been successful since the start of the current problem.

nfailint

The number of steps attempted by the integration function that have failed since the start of the current problem.

tolfacfloat

A tolerance scale factor, $tolfac\ge 1.0$, returned when the integration function exits with $errno$ = 3. If $\text{rtol}$ and $\text{atol}$ are uniformly scaled up by a factor of $tolfac$ and ivp_adams_setup() is called, the next call to the integration function is deemed likely to succeed.

badcmpint

If the integration function returned with $errno$ = 4, $badcmp$ specifies the index of the component which forced the error exit. Otherwise $badcmp$ is $0$.

Raises

NagValueError

(errno $1$)

On entry, $neqf=⟨value⟩$ and $\text{neqf}=⟨value⟩$ in ivp_adams_setup().

Constraint: $neqf=\text{neqf}$ in ivp_adams_setup().

(errno $1$)

Neither of the appropriate two integrator functions has been called.

Notes

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

ivp_adams_diag permits you to extract information about the performance of ivp_adams_roots() or ivp_adams_roots_revcom(). It may only be called after a call to ivp_adams_roots() or ivp_adams_roots_revcom().