sc::HessianUpdate(3)

💅 sc::HessianUpdate(3) — MPQC manual page 💅

okay bestie, this is the MPQC page for sc::HessianUpdate(3). It’s giving “abstract base class with main character energy,” and we’re gonna go through every single detail together, no skips, no cap. 💖

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✨ NAME ✨

sc::HessianUpdate — the abstract class used to specify a hessian update scheme. That’s literally the assignment, and it ate. 💅

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🛠️ SYNOPSIS 🛠️

#include <update.h>

Inherits sc::SavableState.

Inherited by sc::DFPUpdate, and sc::PowellUpdate.

🌸 Public Member Functions 🌸

• HessianUpdate (StateIn &) — constructor that takes a StateIn &. slay.
• HessianUpdate (const Ref< KeyVal > &) — constructor that takes a const Ref< KeyVal > &. also slay.
• 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.
• virtual void update (const RefSymmSCMatrix &hessian, const Ref< Function > &, const RefSCVector &xnew, const RefSCVector &gnew)=0 — this one ends in =0, so it’s pure virtual. The actual update behavior has to come from somewhere else, bestie.
• virtual void set_inverse () — sets the inverse. The page gives us the signature and not much else, and honestly same.
• virtual void apply_transform (const Ref< NonlinearTransform > &) — takes a const Ref< NonlinearTransform > &. that’s the whole tea for this line.

💜 Protected Attributes 💜

• int inverse_hessian_ — this is the int that the detailed description below is talking about.

🫶 Additional Inherited Members 🫶

There are extra inherited members, but this page doesn’t list them. We stay respectful of the mystery. 🫡

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🦋 Detailed Description 🦋

The HessianUpdate abstract class is used to specify a hessian update scheme. It’s the base-class blueprint for that whole situation.

It is used, for example, by QNewtonOpt objects. Based on the value of inverse_hessian_, x and g may be reversed (see Schlegel, Ab initio Methods in Quantum Chemistry I, 1987, p 10).

bestie, that’s the exact reference and page number — do not lose it, it’s iconic. 🎀

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🔥 Member Function Documentation 🔥

void sc::HessianUpdate::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::SavableState.

Reimplemented in sc::PowellUpdate, sc::BFGSUpdate, and sc::DFPUpdate.

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🎀 Author 🎀

Generated automatically by Doxygen for MPQC from the source code.

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and that’s the whole vibe: MPQC source, version 2.3.1, dated Sun Oct 4 2020 — cute little footer energy, sign-off complete, bye bestie 💖✨🦋