sc::TwoBodyThreeCenterInt(3)

💅 NAME 💅

okay so bestie, <pink>sc::TwoBodyThreeCenterInt</pink> is literally the abstract base type for classes that compute integrals involving, yep, two electrons in three Gaussian functions. that's the whole vibe. periodt ✨

Also — this page is straight out of the MPQC manual, so keep that in mind while you scroll, k? 🫶

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🌸 SYNOPSIS 🌸

lowkey the whole shape of it:

#include <tbint.h>

Inherits sc::RefCount.

Inherited by sc::TwoBodyThreeCenterIntV3.

✨ Public Types

• enum tbint_type { eri =0, r12 =1, r12t1 =2, r12t2 =3 } — these are the types of two-body integrals that TwoBodyInt understands (yes, the class name in the original text is TwoBodyInt, not me being sloppy 💀): eri stands for electron repulsion integral, r12 stands for integrals of r12 operator, and r12t1 and r12t2 are integrals of [r12,T1] and [r12,T2] operators. iconic little enum ngl 👑

🎀 Public Member Functions

• int nbasis () const — returns the number of basis functions on center one. yes, "center one" twice, see the next one, it's a mood 😭
• int nbasis1 () const — returns the number of basis functions on center one.
• int nbasis2 () const — returns the number of basis functions on center two.
• int nbasis3 () const — returns the number of basis functions on center three.
• int nshell () const — returns the number of shells on center one.
• int nshell1 () const — returns the number of shells on center one.
• int nshell2 () const — returns the number of shells on center two.
• int nshell3 () const — returns the number of shells on center three.
• Ref< GaussianBasisSet > basis () — returns the basis set on center one.
• Ref< GaussianBasisSet > basis1 () — returns the basis set on center one.
• Ref< GaussianBasisSet > basis2 () — returns the basis set on center two.
• Ref< GaussianBasisSet > basis3 () — returns the basis set on center three.
• virtual const double * buffer (tbint_type type=eri) const — the computed shell integrals get put in the buffer that this member hands you back. 💖
• virtual void compute_shell (int, int, int)=0 — give it three shell indices and the integrals get computed and dropped into the buffer. pure virtual, so no shortcuts bestie.
• virtual int log2_shell_bound (int=-1, int=-1, int=-1)=0 — returns log base 2 of the maximum magnitude of any integral in a shell block obtained from compute_shell. also pure virtual.
• int redundant () const — if redundant is true, then keep the redundant integrals in the buffer. fr fr.
• void set_redundant (int i) — see redundant(). that's the whole description, i don't make the rules 🫠
• virtual void set_integral_storage (size_t storage) — this storage is used to cache computed integrals. cute little cache moment.
• Integral * integral () const — returns the integral factory that was used to create this object. main character factory energy 🏭✨

⭐ Static Public Attributes

• static const int num_tbint_types = 4 — the total number of such types. four. that's it. that's the number. 💀

🦋 Protected Member Functions

• TwoBodyThreeCenterInt (Integral *integral, const Ref< GaussianBasisSet > &bs1, const Ref< GaussianBasisSet > &bs2, const Ref< GaussianBasisSet > &bs3) — the constructor, protected, so it's giving "invite only" 🙈

🌈 Protected Attributes

• Integral * integral_
• Ref< GaussianBasisSet > bs1_
• Ref< GaussianBasisSet > bs2_
• Ref< GaussianBasisSet > bs3_
• double * buffer_
• int redundant_

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💜 Detailed Description 💜

bestie. it's an abstract base type for classes that compute integrals involving two electrons in three Gaussian functions. that's the tea, that's the whole tea. 🍓

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🔥 Member Function Documentation 🔥

virtual const double* sc::TwoBodyThreeCenterInt::buffer (tbint_type type = eri) const [virtual]

the computed shell integrals get put in the buffer returned by this member. and listen — some TwoBodyInt specializations have more than one buffer, so the type argument selects which buffer comes back. if the requested type isn't supported, then 0 is returned. no buffer for you, girlie 💅

virtual void sc::TwoBodyThreeCenterInt::compute_shell (int, int, int) [pure virtual]

given three shell indices, integrals get computed and placed in the buffer. the first two indices correspond to electron 1 and the second index corresponds to electron 2. (yes, that's exactly how the original words it — "the first two indices" and "the second index", i'm just the messenger 😭)

Implemented in sc::TwoBodyThreeCenterIntV3.

virtual int sc::TwoBodyThreeCenterInt::log2_shell_bound (int = -1, int = -1, int = -1) [pure virtual]

returns log base 2 of the maximum magnitude of any integral in a shell block obtained from compute_shell. an index of -1 for any argument indicates any shell. very "idk pick whatever" of it ✨

Implemented in sc::TwoBodyThreeCenterIntV3.

int sc::TwoBodyThreeCenterInt::redundant () const [inline]

if redundant is true, then keep the redundant integrals in the buffer. and the default? true. slay 💖

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🫶 Author 🫶

"Generated automatically by Doxygen for MPQC from the source code." — so nobody actually hand-wrote this one, the robots did it. still ate tho 🤖✨

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ngl this is the vibe check page: abstract base class, three Gaussian functions, two electrons, zero apologies. iykyk 👑

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and that's the page bestie!! 🎀 source says Version 2.3.1, dated Sun Oct 4 2020, and it's sc::TwoBodyThreeCenterInt(3) all day. mwah 💋💖🧚