e04tb is the AD Library version of the primal routine e04tbf. Based (in the C++ interface) on overload resolution, e04tb can be used for primal, tangent and adjoint evaluation. It supports tangents and adjoints of first order.

2 Specification

Fortran Interface

Subroutine e04tb_AD_f (

handle, comp, lidx, idx, ifail)

Integer, Intent (In)	::	lidx, idx(lidx)
Integer, Intent (Inout)	::	ifail
Character (*), Intent (In)	::	comp
Type (c_ptr), Intent (Inout)	::	ad_handle
Type (c_ptr), Intent (In)	::	handle

Corresponding to the overloaded C++ function, the Fortran interface provides five routines with names reflecting the type used for active real arguments. The actual subroutine and type names are formed by replacing AD and ADTYPE in the above as follows:

when ADTYPE is	Real(kind=nag_wp)	then AD is p0w
when ADTYPE is	Type(nagad_a1w_w_rtype)	then AD is a1w
when ADTYPE is	Type(nagad_t1w_w_rtype)	then AD is t1w

C++ Interface

#include <dco.hpp>
#include <nagad.h>
namespace nag {
namespace ad {

void e04tb (

handle_t &ad_handle, void *handle, const char *comp, const Integer &lidx, const Integer idx[], Integer &ifail)

}
}

The function is overloaded on ADTYPE which represents the type of active arguments. ADTYPE may be any of the following types:
double,
dco::ga1s<double>::type,
dco::gt1s<double>::type

Note: this function can be used with AD tools other than dco/c++. For details, please contact NAG.

3 Description

e04tb is the AD Library version of the primal routine e04tbf.

e04tbf is a part of the NAG optimization modelling suite and allows you to enable various components of the existing model which were previously disabled by e04tcf. For further information see Section 3 in the documentation for e04tbf.

4 References

5 Arguments

In addition to the arguments present in the interface of the primal routine, e04tb includes some arguments specific to AD.

A brief summary of the AD specific arguments is given below. For the remainder, links are provided to the corresponding argument from the primal routine. A tooltip popup for all arguments can be found by hovering over the argument name in Section 2 and in this section.

1: ad_handle – nag::ad::handle_t Input/Output: On entry: a configuration object that holds information on the differentiation strategy. Details on setting the AD strategy are described in AD handle object in the NAG AD Library Introduction.
2: handle – Type(c_ptr) Input
3: comp – character Input
4: lidx – Integer Input
5: idx(lidx) – Integer array Input
6: ifail – Integer Input/Output

6 Error Indicators and Warnings

e04tb preserves all error codes from e04tbf and in addition can return:

$ifail = - 89$: An unexpected AD error has been triggered by this routine. Please contact NAG.
See Error Handling in the NAG AD Library Introduction for further information.

$ifail = - 199$: The routine was called using a strategy that has not yet been implemented.
See AD Strategies in the NAG AD Library Introduction for further information.