sc::MolecularHessian(3)

💖 sc::MolecularHessian — an MPQC manual page, bestie edition 💖

okay so real talk, this is a page from the MPQC manual set, and it's all about sc::MolecularHessian. buckle up, it's giving "abstract base class with main character energy" 🧚✨

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🌸 NAME 🌸

sc::MolecularHessian — listen. MolecularHessian is an abstract class that computes a molecule's second derivatives of the energy with respect to changes in the nuclear coordinates. that's the whole vibe. that's what she does. 💅

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✨ SYNOPSIS ✨

#include <hess.h>

she inherits from sc::SavableState. 🫶

and she gets inherited by sc::DiagMolecularHessian, sc::FinDispMolecularHessian, sc::GuessMolecularHessian, and sc::ReadMolecularHessian. a whole little family tree, iconic. 🌈

🎀 Public Member Functions

• MolecularHessian(const Ref<KeyVal> &) — the MolecularHessian KeyVal constructor, which is used to generate a MolecularHessian derivative object from the input, no cap.
• MolecularHessian(StateIn &) — the other constructor, taking a StateIn. slay.
• void save_data_state(StateOut &) — saves the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them.
• RefSCDimension d3natom() — returns a RefSCDimension. that's it, that's the whole job. ✨
• Ref<SCMatrixKit> matrixkit() const — returns the matrix kit, const and everything.
• virtual RefSymmSCMatrix cartesian_hessian()=0 — returns the cartesian hessian. note the =0, she is pure virtual, so like... you can't instantiate her, bestie. she's a concept. 😭
• virtual void set_energy(const Ref<MolecularEnergy> &energy) — some MolecularHessian specializations require a molecular energy object, so here's the hook for that.
• virtual MolecularEnergy * energy() const — this returns a MolecularEnergy object, if it's used by this specialization.

⭐ Static Public Member Functions

• static RefSCMatrix cartesian_to_symmetry(const Ref<Molecule> &m, Ref<PointGroup> pg=0, Ref<SCMatrixKit> kit=0) — finds the transformation matrix from cartesian to symmetry coordinates. look at those defaults, pg=0 and kit=0, gorgeous. 💜
• static void write_cartesian_hessian(const char *filename, const Ref<Molecule> &m, const RefSymmSCMatrix &hess) — writes the hessian in a simple text format.
• static void read_cartesian_hessian(const char *filename, const Ref<Molecule> &m, const RefSymmSCMatrix &hess) — reads the hessian from a simple text format. yes bestie, they're a matched set, we love symmetry. 🦋

🧚 Protected Attributes

• Ref<Molecule> mol_
• RefSCDimension d3natom_
• Ref<SCMatrixKit> matrixkit_

💫 Additional Inherited Members

(the usual inherited goodies, nothing extra to report — she's a SavableState girlie)

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🔥 Detailed Description 🔥

so, again, because it bears repeating: MolecularHessian is an abstract class that computes a molecule's second derivatives of the energy with respect to changes in the nuclear coordinates. literally the entire personality. periodt. 👑

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🍓 Constructor & Destructor Documentation 🍓

sc::MolecularHessian::MolecularHessian(const Ref<KeyVal> &)

the MolecularHessian KeyVal constructor is used to generate a MolecularHessian derivative object from the input. it reads the keywords below. 👇

• molecule — type Molecule, default none, description: The Molecule object. that's the one keyword. she's lowkey minimal and I respect it. ✨

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💀 Member Function Documentation 💀

virtual MolecularEnergy* sc::MolecularHessian::energy() const [virtual]

this returns a MolecularEnergy object, if used by this specialization. otherwise null is returned. 🙈

Reimplemented in sc::FinDispMolecularHessian.

void sc::MolecularHessian::save_data_state(StateOut &) [virtual]

saves the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them. and heads up bestie: this must be implemented by the derived class if the class has data. no skipping. 😤

Reimplemented from sc::SavableState.

Reimplemented in sc::DiagMolecularHessian, sc::GuessMolecularHessian, and sc::ReadMolecularHessian.

virtual void sc::MolecularHessian::set_energy(const Ref<MolecularEnergy> & energy) [virtual]

some MolecularHessian specializations require a molecular energy object. the default implementations of this ignore the argument. she's literally just vibing and not listening, and honestly? same. 💅

Reimplemented in sc::FinDispMolecularHessian.

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👑 Author 👑

generated automatically by Doxygen for MPQC from the source code. she wasn't hand-written, she was born this way. 🎀

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friendly reminder that this is Version 2.3.1, dated Sun Oct 4 2020 — the Sun Oct 4 2020 is the date on the page and 2.3.1 is the version, fr fr. 🤍

okay that's the whole page, you ate it up, go read the derived classes next bestie 🫶💖✨