slepc-3.20.1 2023-11-27

NEPSetJacobian

Sets the function to compute the Jacobian T'(lambda) as well as the location to store the matrix.

#include "slepcnep.h" 
PetscErrorCode NEPSetJacobian(NEP nep,Mat A,PetscErrorCode (*jac)(NEP nep,PetscScalar lambda,Mat J,void *ctx),void *ctx)

Collective

	nep	- the NEP context
	A	- Jacobian matrix
	jac	- Jacobian evaluation routine (if NULL then NEP retains any previously set value)
	ctx	- [optional] user-defined context for private data for the Jacobian evaluation routine (may be NULL) (if NULL then NEP retains any previously set value)

 PetscErrorCode jac(NEP nep,PetscScalar lambda,Mat J,void *ctx)

	nep	- the NEP context
	lambda	- the scalar argument where T'(.) must be evaluated
	J	- matrix that will contain T'(lambda)
	ctx	- (optional) user-defined context, as set by NEPSetJacobian()

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