---
name: "sc_BFGSUpdate"
section: "3"
platform: "linux"
package: "libsc-doc"
version: "2.3.1-22"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/sc_BFGSUpdate"
---

# sc\_BFGSUpdate(3)

The DFPUpdate class is used to specify a Broyden, Fletcher, Goldfarb, and Shanno hessian update scheme.

## NAME

sc::BFGSUpdate - The **DFPUpdate** class is used to specify a Broyden, Fletcher, Goldfarb, and Shanno hessian update scheme.

## SYNOPSIS

`#include <update.h>`

Inherits **sc::DFPUpdate**.

### Public Member Functions

**BFGSUpdate** (**StateIn** &)\
 **BFGSUpdate** (const **Ref**\< **KeyVal** \> &)\
 void **save\_data\_state** (**StateOut** &)\
 Save the base classes (with save\_data\_state) and the members in the same order that the **StateIn** CTOR initializes them.  void **update** (const **RefSymmSCMatrix** &ihessian, const **Ref**\< **Function** \> &, const **RefSCVector** &xnew, const **RefSCVector** &gnew)\

### Additional Inherited Members

## Detailed Description

The **DFPUpdate** class is used to specify a Broyden, Fletcher, Goldfarb, and Shanno hessian update scheme.

This hessian update method is the recommended method for use with **QNewtonOpt** objects. \

## Member Function Documentation

### void sc::BFGSUpdate::save\_data\_state (StateOut &)` [virtual]`

Save the base classes (with save\_data\_state) and the members in the same order that the **StateIn** CTOR initializes them. This must be implemented by the derived class if the class has data.

Reimplemented from **sc::DFPUpdate**.

### void sc::BFGSUpdate::update (const RefSymmSCMatrix & ihessian, const Ref\< Function \> &, const RefSCVector & xnew, const RefSCVector & gnew)` [virtual]`

Reimplemented from **sc::DFPUpdate**.

## Author

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