Aerial of Branching 1

|↑| Aerial | Aerial of Branching

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The Branching trunk is for standard concepts.

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Academics

{toc}

• Bibliography ○𓆪
• Zotero ○›

Applications

• ❪𖣐₃ₐ’❫ Citation Managers ○

Classes

• Academic Journal ○꠹
• Citation ○꠹

Hubs

• arXiv ○➛

Accretion

Accretion Disk & {float}

• Accretion Disk Corona ○꠹

Classes

• Accretion Disk ○꠹

Common

• Advection-Dominated Accretion Flow (ADAF) ○
• Geometric Thickness ○
• Magnetorotational Instability (MRI) ○

Address

Address Space

• Kernel Space ○
• User Space ○

Classes

• Addressing Mode ○꠹

Classes of Spaces

• Address Space ○꠹

Common

• Addressability ○

Algebra

Common

• Substitution ○

Computer Algebra

• Computer Algebra System (CAS) ○꠹

Domains & Domains

• Computer Algebra ○𓆪

Exponential Function

• Exponential Function (eˣ) ○◂

Functions

• Absolute Value (┃x┃) ○◂
• Exponential Function (nˣ) ○◂
• Logarithm (logₙ₍x₎) ○◂

Functions: Multiplication

• Factorial (!) ○◂

Logarithm

• Common Logarithm (log₁₀₍x₎) ○◂
• Natural Logarithm (ln₍x₎) ○◂

Recipes: Polynomial & Long Division

• Polynomial Long Division ○◂

Rules

• Associative Property ○◂
• Commutative Property ○◂
• Distributive Property ○◂
• Polynomial Remainder Theorem ○◂
• Zero-Product Property ○◂

Rules: Binomial

• Binomial Theorem ○◂

Rules: Quadratic

• Quadratic Formula ○◂

Analysis

Common

• Frequency Domain ○
• Time Domain ○

Domains

• Fourier Analysis ○𓆪

Functions

• Delta Function ○◂
• Fourier Transform ○◂

Functions: Factorial

• Gamma Function (Γ₍x₎) ○◂

Operations

• Convolution ○◂
• Deconvolution ○◂

Architecture

{toc}

• x86 ○˒

Architectural Units

• Arithmetic Logic Unit (ALU) ○꠹
• Control Unit ○꠹
• Execution Unit ○꠹
• Instruction Unit ○꠹
• Load-Store Unit ○꠹
• Processor ○꠹

Architectural Units: Processor

• Central Processing Unit (CPU) ○꠹

Classes

• Instruction Set Architecture (ISA) ○꠹

Common

• Microarchitecture ○

Instruction Set Architectures

• ARM ○˒
• PowerPC ○˒

Sets

• ❪◑❫ Architectural Units ○
• ❪◑❫ Instruction Set Architectures ○

Arithmetic

Binary Arithmetic

• Fixed-Point Arithmetic ○
• Floating-Point Arithmetic ○

Classes

• Carry ○꠹

Common & Common

• Binary Arithmetic ○

Functions

• Greatest Common Divisor (GCD) ○◂
• Least Common Multiple (LCM) ○◂

Functions: Least Common Multiple

• Lowest Common Denominator (LCD) ○◂

Operations

• Addition (+) ○◂
• Division (÷) ○◂
• Multiplication (×) ○◂
• Root (ⁿ√x) ○◂
• Subtraction (-) ○◂

Operations: Multiplication

• Exponentiation (xⁿ) ○◂

Recipes: Division

• Long Division ○◂

Root

• Cube Root (∛x) ○◂
• Square Root (√x) ○◂

Astronomy

{toc}

• Accretion ○
• Astropy ○›
• Orbit ○꠹

Astronomical Coordinate Systems

• International Celestial Reference System (ICRS) ○˒
• World Coordinate System (WCS) ○˒

Astronomical Coordinates

• ❪𝛿’❫ Astronomical Dates ○
• Declination ○◂
• Right Ascension ○◂

Astronomical Dates

• ❪𝛿’❫ Epochs ○
• Julian Day (JD) ○◂

Astronomical Dates: Julian Day

• Heliocentric Julian Day (HJD) ○◂
• Modified Julian Day (MJD) ○◂

Astronomical Objects

• ❪◑❫ Galaxies ○
• ❪◑❫ Galaxy Clusters ○
• ❪◑❫ Nebulae ○
• ❪◑❫ Novae ○
• ❪◑❫ Star Systems ○
• ❪◑❫ Supernova Remnants ○
• ❪◑❫ White Dwarves ○

Black Hole Classes

• Astrophysical Jet ○꠹

Classes

• Astronomical Object ○꠹
• Catalog ○꠹
• Cosmic Ray ○꠹
• Epoch ○꠹
• Lagrange Point ○꠹
• Light Curve ○꠹
• Occultation ○꠹
• Stellar Wind ○꠹
• Survey ○꠹

Classes & Classes

• Color-Color Diagram ○꠹

Classes of Astronomical Instrumentation

• Astronomical Interferometer ○꠹

Classes of Astronomical Objects

• Compact Object ○꠹
• Galaxy ○꠹
• Galaxy Cluster ○꠹
• Gamma-Ray Burst ○꠹
• Nebula ○꠹
• Nova ○꠹
• Pulsar ○꠹
• Star ○꠹
• Supernova ○꠹
• Tidal Disruption Event ○꠹

Classes of Astronomical Objects: {toc}

• Black Hole ○꠹

Classes of Astronomical Objects: Active Galactic Nucleus

• Blazar ○꠹
• Quasar ○꠹

Classes of Astronomical Objects: Compact Object

• White Dwarf ○꠹

Classes of Astronomical Objects: High-Energy Astrophysics Classes

• X-Ray Binary (XRB) ○꠹

Classes of Astronomical Objects: Neutron Star

• Magnetar ○꠹

Classes of Astronomical Objects: Star

• Binary Star ○꠹
• Cataclysmic Variable Star (CV) ○꠹
• Dwarf Star ○꠹
• Star System ○꠹
• Wolf-Rayet Star ○꠹

Classes of Astronomical Objects: Supernova

• Hypernova ○꠹
• Supernova Remnant (SNR) ○꠹

Common

• Azimuth ○
• Celestial Sphere ○
• Gravitational Collapse ○
• Interstellar Medium ○
• Limb Darkening ○
• Observation ID (ObsID) ○
• Outer Space ○
• Prograde Motion ○
• Retrograde Motion ○
• Roche Lobe ○
• Roche Sphere ○
• Stellar Classification ○
• Telluric Contamination ○

Common & Common

• Color Index ○

Constellations

• Ophiuchus ○˒

Domains

• Astrometry ○𓆪
• Extragalactic Astronomy ○𓆪
• Galactic Astronomy ○𓆪
• Observational Astronomy ○𓆪
• Optical Astronomy ○𓆪

Domains: Gravitational Wave

• Gravitational-Wave Astronomy ○𓆪

Epochs

• B1950 ○◂
• J2000 ○◂

File Formats

• FITS ○˒

Functions

• Initial Mass Function (IMF) ○◂
• Mass Function ○◂

Galaxies

• Andromeda Galaxy ❍
• Large Magellanic Cloud ❍
• Milky Way ❍
• Triangulum Galaxy ❍

Galaxy Clusters

• Local Group ❍

Gravitational-Wave Observatories

• LIGO ○´
• LISA ○´

High-Energy Astrophysics Classes

• Active Galactic Nucleus (AGN) ○꠹
• Neutron Star ○꠹

High-Energy Astrophysics Instrumentation

• ❪𖣐₂’❫ Gamma-Ray Observatories ○
• ❪𖣐₂’❫ X-Ray Observatories ○

High-Energy Astrophysics Sets

• ❪◑❫ X-Ray Binaries ○

Hubs

• Astrophysics Data System (ADS) ○➛
• General Coordinates Network (GCN) ○➛
• SIMBAD ○➛
• The Astronomer’s Telegram (ATel) ○➛
• Unified Astronomy Thesaurus ○➛

Instrumentation

• ❪𖣐₂’❫ Observatories ○

Magnitude

• Absolute Magnitude ○◂
• Apparent Magnitude ○◂

Methods: Interferometry

• Very-Long-Baseline Interferometry (VLBI) ○𓆪

Novae

• T Coronae Borealis ❍

Observatories

• ❪𖣐₂’❫ Gravitational-Wave Observatories ○

Organizations

• ❪◑❫ Space Agencies ○
• American Astronomical Society (AAS) ○˒
• Center for Astrophysics (CfA) ○˒

Particulars

• International Space Station (ISS) ○´

Quantities

• ❪𝛿’❫ Astronomical Coordinates ○
• Magnitude (mag) ○◂
• Spectral Index (α) ○◂
• Velocity Curve Half-Amplitude (K₂) ○◂

Quantities: Luminosity

• Eddington Luminosity (L𝘌𝘥𝘥) ○◂

Rules

• Kepler’s Laws ○◂

Sets

• ❪◑❫ Astronomical Objects ○
• ❪◑❫ Constellations ○
• ❪◑❫ Surveys ○
• ❪◑❫ Telemetry Networks ○

Software

• DS9 ○›

Source Mass

• Primary Mass (M₁) ○◂
• Secondary Mass (M₂) ○◂

Space Agencies

• European Space Agency (ESA) ○˒
• ISRO ○˒
• JAXA ○˒
• NASA ○˒

Spectral Fitting Parameters

• Absorbing Column Density (nH) ○◂
• Redshift (z) ○◂
• Source Distance (D) ○◂
• Source Mass (M) ○◂

Spectral Types

• B-Type ○
• K-Type ○
• O-Type ○

Standards

• ❪◑❫ Astronomical Coordinate Systems ○

Star Systems

• Alpha Centauri ❍

Stellar Classification

• ❪◑❫ Spectral Types ○

Supernova Remnants & Nebulae

• Crab Nebula ❍

Surveys

• Sloan Digital Sky Survey ○˒

Telemetry Networks

• Deep Space Network (DSN) ○˒
• Tracking and Data Relay Satellite System (TDRSS) ○˒

Units of Length

• Astronomical Unit (AU) ○◂
• Parsec (pc) ○◂

Binary

{goofy}

• ❪𝛿₂ᵢ’❫ Units of Information ○

Bit

• Bit Numbering ○

Bit & Stream

• Bitstream ○꠹

Common

• Overflow ○
• Sign Extension ○

Sets

• ❪◑❫ Signed Number Representations ○

Signed Number Representations

• Method of Complements ○
• Sign–Magnitude ○

Signed Number Representations: Method of Complements

• Ones’ Complement ○
• Two’s Complement ○

Units of Information

• Bit (b) ○◂

Units of Information: Bit

• Byte (B) ○◂

Units of Information: Byte

• Gigabyte (GB) ○◂
• Kilobyte (KB) ○◂
• Megabyte (MB) ○◂

Black Hole

Classes of Black Holes

• Intermediate-Mass Black Hole ○꠹
• Primordial Black Hole ○꠹
• Stellar-Mass Black Hole ○꠹
• Supermassive Black Hole ○꠹

Common

• Ergosphere ○
• Event Horizon ○
• Penrose Process ○

Boolean

Classes

• Don’t-Care Term ○꠹
• Implicant ○꠹
• K-Map ○꠹
• Maxterm ○꠹
• Minterm ○꠹
• Truth Table ○꠹

Classes of Functions

• Boolean Function ○꠹

Implicant

• Prime Implicant ○꠹

Rules

• Consensus Theorem ○◂
• De Morgan’s Laws ○◂

State Classes

• State Table ○꠹

C

C Compilers & C++ Compilers

• Microsoft Visual C++ ○›

Classes of C Files

• Header File ○꠹

Libraries

• C Standard Library ○›

Libraries: SQL

• SQLite ○›

C++

{signature}

• ﹤algorithm﹥ ○›ꟲᴾᴾ
• ﹤iomanip﹥ ○›ꟲᴾᴾ
• ﹤iostream﹥ ○›ꟲᴾᴾ
• ﹤istream﹥ ○›ꟲᴾᴾ
• ﹤string﹥ ○›ꟲᴾᴾ
• Template ○꠹ꟲᴾᴾ

{toc}

• C++ Standard Library ○›
• Eigen ○›

Hubs

• cppreference.com ○➛

Calculus

{alias}

• Differentiation (d∕dx) ○◂

Classes

• Antiderivative ○꠹
• Derivative ○꠹
• Infinitesimal ○꠹
• Integral ○꠹
• Series ○꠹

Common

• Differential ○
• Gradient ○

Differential & {toc}

• Differential Equation ○꠹

Operations

• Antidifferentiation (∫) ○◂
• Limit (lim) ○◂

Operations: Summation

• Integration (ₐ∫ᵇ) ○◂

Rules

• L’Hôpital’s Rule ○◂

Series

• Power Series ○꠹
• Taylor Series ○◂

Chemistry

Chemical Elements

• Hydrogen (H) ❍
• Iron (Fe) ❍
• Oxygen (O) ❍
• Silicon (Si) ❍

Classes

• Ion ○꠹
• Isotope ○꠹
• Lewis Structure ○꠹

Classes & Classes

• Atom ○꠹

Common

• Elemental Abundance ○
• Stoichiometry ○

Hydrogen

• Tritium ❍

Physical Dimensions

• Amount of Substance (n) ○◂

Quantities: Mass

• Atomic Mass ○◂

Sets

• ❪◑❫ Chemical Elements ○

Sets & Sets

• ❪◑❫ States of Matter ○

States of Matter

• Solid ○

States of Matter & Fluids

• Gas ○
• Liquid ○
• Plasma ○

Classical Mechanics

Classes

• Harmonic Oscillator ○꠹

Common

• Inertia ○

Domains

• Dynamics ○𓆪
• Hamiltonian Mechanics ○𓆪
• Kinematics ○𓆪
• Lagrangian Mechanics ○𓆪
• Newtonian Mechanics ○𓆪
• Statics ○𓆪

Inertia & Frame of Reference

• Inertial Frame of Reference ○

Rules

• Newton’s Laws of Motion ○◂

Cloudflare

{toc}

• Wrangler ○›

Color

Classes of Spaces

• Color Space ○꠹

Common

• Spectral Color ○

Combinatorics

Classes

• Combination ○꠹
• Permutation ○꠹

Rules

• Rule of Product ○◂

Computer

{alias}

• Asynchronous I∕O ○
• Input∕Output ○

{disconnect}

• QEMU ○›

{signature}

• Binary ○꠹ꟳᴵᴸᴱ
• Field ○꠹ꟲᴼᴹᴾ
• Volume ○꠹ꟲᴼᴹᴾ

{toc}

• Computer Architecture ○
• Computer Graphics ○
• File ○꠹
• GNU ○›
• Memory ○
• Operating System ○꠹
• Unix ○›
• URL ○꠹
• Windows ○›

Applications

• ❪𖣐₃ₐ’❫ eBook Software ○
• ❪𖣐₃ₐ’❫ Office Suites ○
• ❪𖣐₃ₐ’❫ Password Managers ○
• ❪𖣐₃ₐ’❫ PDF Software ○
• ❪𖣐₃ₐ’❫ Presentation Programs ○
• ❪𖣐₃ₐ’❫ Spreadsheets ○
• ❪𖣐₃ₐ’❫ Text Editors ○
• ❪𖣐₃ₐ’❫ Web Browsers ○
• ❪𖣐₃ₐ’❫ Word Processors ○

Character

• Character Encoding ○

Classes

• Array ○꠹
• Breadcrumb ○꠹
• Character ○꠹
• Computer Language ○꠹
• Emulator ○꠹
• Environment Variable ○꠹
• Executable ○꠹
• Modal ○꠹
• Path ○꠹
• Pipeline ○꠹
• Platform ○꠹
• Program ○꠹
• Server ○꠹
• Stream ○꠹
• Turing Machine ○꠹
• Virtual Drive ○꠹
• Virtual Machine ○꠹

Classes & {toc}

• URI ○꠹

Classes of Data

• Document ○꠹
• Image ○꠹
• Table ○꠹
• Text ○꠹

Classes of Files

• Archive File ○꠹
• Hidden File ○꠹
• Object File ○꠹
• Sidecar File ○꠹

Classes of Files: Configuration

• Configuration File ○꠹

Classes of Files: Programmatic Classes

• Package ○꠹

Classes of Memory

• Non-Volatile Memory ○
• Volatile Memory ○

Classes of Memory: Non-Volatile Memory

• Flash Memory ○
• Read-Only Memory (ROM) ○

Classes of Memory: Volatile Memory

• Random-Access Memory (RAM) ○

Classes of Software

• Application Software ○꠹
• System Software ○꠹
• Utility Software ○꠹

Classes of Software & Classes of Data

• Spreadsheet ○꠹

Classes of Storage

• Disk Storage ○
• Magnetic Storage ○
• Object Storage ○
• Solid-State Storage ○

Common

• Blocking ○
• Configuration ○
• Disk Partitioning ○
• Execution ○
• Mounting ○
• Parallel Computing ○
• Storage ○
• Virtualization ○

Computer Engineering Sets

• ❪◑❫ Hardware Description Languages ○

Computers

• ENIAC ○´

Computers: ENIAC

• EDVAC ○´

Disk Storage

• Hard Drive (HDD) ○꠹
• Optical Disk ○꠹

Domains

• Scientific Computing ○𓆪

eBook Software

• Calibre ○›
• KOReader ○›

File Formats

• CSV ○˒
• EPUB ○˒
• ISO ○˒
• JSON ○˒
• TOML ○˒

File Formats: Office Open XML

• XLSX ○˒

File Formats: PostScript

• PDF ○˒

File Formats: XML

• Office Open XML ○˒

Information Domains

• Data Science ○𓆪

Input

• Reading ○

Input Devices

• Keyboard ○꠹

Input-Output

• Input ○
• Output ○

Interpreters

• ❪𖣐₃ⱼₐ’❫ JIT Compilers ○

Linux Distributions

• Debian ○›
• Red Hat Enterprise Linux ○›

Linux Distributions: Debian

• Ubuntu ○›

Linux Distributions: Red Hat Enterprise Linux

• CentOS ○›
• Rocky Linux ○›

Office Suites

• LibreOffice ○›
• Microsoft Office ○›

Operating Systems: Unix

• ❪𖣐₃’❫ Unix-Likes ○

Operating Systems: Windows

• ❪𖣐₃’❫ Windows Versions ○

Operations

• Pop ○◂
• Push ○◂

Operations: Division

• Modulo ○◂

Output

• Writing ○

Output Devices

• Display ○꠹

Output Devices: Display

• Monitor ○꠹

Page Description Languages

• PostScript ○˒

Password Managers

• KeePass ○›

Password Managers: KeePass

• KeePassXC ○›

PDF Software

• PDFgear ○›

Peripherals

• ❪◑❫ Input Devices ○
• ❪◑❫ Output Devices ○

Presentation Programs: LibreOffice

• LibreOffice Impress ○›

Presentation Programs: Microsoft Office

• PowerPoint ○›

Processor

• Microprocessor ○꠹

Programmatic Classes

• Markup Language ○꠹
• Programming Language ○꠹

Programmatic Sets

• ❪◑❫ Markup Languages ○
• ❪◑❫ Programming Languages ○

Random-Access Memory

• Dynamic Random-Access Memory (DRAM) ○
• Static Random-Access Memory (SRAM) ○

Read-Only Memory

• Programmable Read-Only Memory (PROM) ○

Sets

• ❪◑❫ Computer Languages ○
• ❪◑❫ Computers ○️
• ❪◑❫ Peripherals ○

Software

• ❪𖣐₃’❫ Operating Systems ○

Solid-State Storage

• Solid-State Drive (SSD) ○꠹

Spreadsheets: {disconnect}

• Excel ○›

Spreadsheets: LibreOffice

• LibreOffice Calc ○›

Standards

• ASCII ○˒
• Unicode ○˒
• USB ○˒

Standards & Standards

• IEEE 754 ○˒

System Software

• ❪𖣐₃ⱼ’❫ Windowing Systems ○

System Software: Virtualization

• ❪𖣐₃ⱼ’❫ Virtualizers ○

Text Editors

• Emacs ○›
• Vim ○›

Typographical Sets

• ❪◑❫ Page Description Languages ○

Unicode

• UTF-8 ○˒

Units

• FLOPS ○◂

Unix-Likes

• BSD ○›
• Solaris ○›

Unix-Likes: {toc}

• Linux ○›

Unix-Likes: BSD

• FreeBSD ○›

Unix-Likes: Linux

• ❪𖣐₃’❫ Linux Distributions ○

Utilities

• ❪𖣐₃ₖ’❫ Bundlers ○

Virtualization

• Hardware Virtualization ○

Virtualizers

• VirtualBox ○›

Web Browsers

• Chromium ○›

Web Browsers: Chromium

• Google Chrome ○›
• Microsoft Edge ○›

Windowing Systems

• X Window System ○˒

Word Processors: LibreOffice

• LibreOffice Writer ○›

Word Processors: Microsoft Office

• Word ○›

Computer Engineering

{signature}

• Word ○꠹ꟲᴼᴹᴾ

Classes

• Bus ○꠹
• Datapath ○꠹
• Hardware Register ○꠹
• Instruction ○꠹
• Interrupt ○꠹
• Opcode ○꠹
• Program Counter (PC) ○꠹
• Register File ○꠹

Classes of Processor Registers

• Instruction Register ○꠹
• Memory Address Register (MAR) ○꠹
• Memory Buffer Register (MBR) ○꠹
• Status Register ○꠹

Common

• Instruction Cycle ○

Hardware Register

• Processor Register ○꠹

Computer Network

{toc}

• Internet ○˒

Classes

• Hostname ○꠹
• Packet ○꠹

Sets

• ❪◑❫ Hostnames ○

Continuum Mechanics

Common

• Advection ○
• Entrainment ○

Domains

• Magnetohydrodynamics (MHD) ○𓆪

Quantities

• Buoyancy ○◂
• Stress ○◂
• Viscosity ○◂

Cosmology

Classes

• Distance Measure ○꠹
• Weakly Interacting Massive Particle (WIMP) ○꠹

Common

• Dark Energy ○
• Dark Matter ○

Data

Bin

• Binning ○

Classes

• Bin ○꠹
• Database ○꠹
• Histogram ○꠹
• Pixel ○꠹

Common

• Data Compression ○
• Data Recovery ○
• Data Reduction ○
• Digital Data ○
• Metadata ○
• Sorting ○

Data Compression

• Lossless Compression ○
• Lossy Compression ○

Programmatic Classes

• Lookup Table ○꠹

Table

• Column ○꠹
• Row ○꠹

Differential Equation

Classes

• Boundary Value Problem ○꠹

Electrical Engineering

{missingno}

• Logic Design ○𓆪

Adder

• Full Adder ○꠹
• Half Adder ○꠹

Address Classes

• Address Decoder ○꠹

Circuit Devices

• Adder ○꠹
• Comparator ○꠹
• Decoder ○꠹
• Encoder ○꠹
• Multiplexer (MUX) ○꠹
• Subtractor ○꠹

Circuits & Semiconductor Devices

• ❪◑❫ Integrated Circuits ○

Classes

• Clock Signal ○꠹
• Conductor ○꠹
• Counter ○꠹
• Dual In-Line Package (DIP) ○꠹
• Electronic Component ○꠹
• Flip-Flop ○꠹
• Insulator ○꠹
• Junction ○꠹
• Logic Level ○꠹
• Semiconductor ○꠹
• Wire ○꠹

Classes of Circuits

• Asynchronous Circuit ○꠹
• Electronic Circuit ○꠹
• Parallel Circuit ○꠹
• Series Circuit ○꠹
• Short Circuit ○꠹

Classes of Circuits & Classes of Semiconductor Devices

• Integrated Circuit (IC) ○꠹

Classes of Electronic Components

• Switch ○꠹

Classes of Electronic Components: Capacitance

• Capacitor ○꠹

Classes of Electronic Components: Resistance

• Resistor ○꠹

Classes of Electronic Components: Semiconductor

• Semiconductor Device ○꠹

Classes of High-Energy Astrophysics Instrumentation

• Charge-Coupled Device (CCD) ○꠹

Classes of Integrated Circuits

• Programmable Logic Device (PLD) ○꠹

Classes of PLDs

• Field-Programmable Gate Array (FPGA) ○꠹

Classes of Semiconductor Devices

• Diode ○꠹
• Transistor ○꠹

Common

• Aperture ○
• Circuit Simulation ○
• Combinational Logic ○
• Gain ○
• Ground ○
• Sequential Logic ○
• Vignetting ○

Domains

• Electronics ○𓆪

Domains & Domains

• Telecommunications ○𓆪

Electronic Components

• ❪◑❫ Semiconductor Devices ○

Electronic Test Equipment

• Ammeter ○꠹
• Multimeter ○꠹
• Oscilloscope ○꠹
• Voltmeter ○꠹
• Wattmeter ○꠹

Field-Effect Transistor

• MOSFET ○

Flip-Flop

• D Flip-Flop ○꠹
• JK Flip-Flop ○꠹

Integrated Circuit

• IC Power-Supply Pin ○꠹

Integrated Circuits

• ❪◑❫ 4000-Series Integrated Circuits ○

Logic Gates: Conjunction

• AND Gate ○꠹

Logic Gates: Disjunction

• OR Gate ○꠹

Logic Gates: Exclusive Disjunction

• XOR Gate ○꠹

Logic Gates: Exclusive Non-Disjunction

• XNOR Gate ○꠹

Logic Gates: Negation

• Inverter (NOT Gate) ○꠹

Logic Gates: Non-Disjunction

• NOR Gate ○꠹

Logic Gates: Sheffer Stroke

• NAND Gate ○꠹

MOSFET

• CMOS ○

Organizations

• Institute of Electrical and Electronics Engineers (IEEE) ○˒

Resistor

• Pull-Up Resistor ○꠹

Rules

• Kirchhoff’s Voltage Law ○◂
• Ohm’s Law ○◂

Sets

• ❪◑❫ Circuit Devices ○
• ❪◑❫ Circuits ○
• ❪◑❫ Electronic Components ○
• ❪◑❫ Electronic Test Equipment ○
• ❪◑❫ Logic Gates ○

Transistor

• Field-Effect Transistor (FET) ○꠹

Electricity

Electrical Engineering Concepts

• Alternating Current (AC) ○
• Direct Current (DC) ○

Physical Dimensions

• Current (I) ○◂

Quantities

• Capacitance (C) ○◂
• Charge (q) ○◂
• Conductance (G) ○◂
• Electric Potential (V) ○◂
• Electromotive Force (emf) ○◂
• Inductance (L) ○◂
• Resistance (R) ○◂

Quantities: Electric Potential

• Voltage (∆V) ○◂

Quantities: Electromagnetic Field

• Electric Field ○◂

Quantities: Flux

• Electric Flux ○◂

Quantities: Power

• Electric Power (P) ○◂

Units: Capacitance

• Farad (F) ○◂

Units: Charge

• Coulomb (C) ○◂

Units: Current

• Ampere (A) ○◂

Units: Electric Potential & Voltage & Electromotive Force

• Volt (V) ○◂

Units: Inductance

• Henry (H) ○◂

Units: Resistance

• Ohm (Ω) ○◂

Electromagnetism

{signature}

• Absorption ○ᴱᴸᴱ

{toc}

• Polarimetry ○𓆪

Common

• Light ○
• Photoelectric Effect ○
• Polarization ○

Common & Common

• Ionization ○

Ionization

• Photoionization ○

Methods

• Interferometry ○𓆪

Quantities

• Electromagnetic Field ○◂

Engineering

{missingno}

• Engineering Design ○𓆪

Classes

• Surrogate Model ○꠹
• Transfer Function ○꠹

File

Classes

• File Format ○꠹
• Filename ○꠹

Common

• File Synchronization ○

Filename

• Filename Extension ○꠹

File System

Classes

• Directory ○꠹
• Fork ○꠹ꟳᴵᴸᴱˢʸˢᵀᴱᴹ

Common

• Driver Letter Assignment ○
• File System Permissions ○

Sets

• ❪◑❫ Directories ○

Function

{signature}

• Parameter ○꠹ꟳᵁᴺꟲᵀᴵᴼᴺ

Classes

• Moment ○꠹

Common

• Argument of a Function ○
• Codomain ○
• Domain ○
• Image ○
• Range of a Function ○

Geometric Concepts

• Graph of a Function ○

Geometry

Classes

• Angle ○꠹
• Conic Section ○꠹
• Coordinate System ○꠹
• Curve ○꠹
• Fractal ○꠹
• Grid ○꠹
• Line ○꠹
• Parabola ○꠹
• Plane ○꠹
• Solid Angle ○꠹

Common

• Collinearity ○
• Euclidean Distance ○
• Isotropy ○
• Origin ○
• Parallel ○
• Position ○
• Radius ○
• Standard Basis ○

Domains

• Euclidean Geometry ○𓆪
• Topology ○𓆪

Sets

• ❪◑❫ Shapes ○

Shapes

• Circle ○꠹
• Parralelogram ○꠹
• Polygon ○꠹
• Quadrilateral ○꠹
• Square ○꠹
• Torus ○꠹
• Triangle ○꠹

Spaces

• 1D ○◂
• 2D ○◂
• 3D ○◂

Structures: Circle

• Unit Circle ○◂

Structures: Square

• Unit Square ○◂

Units: Angle

• Degree (°) ○◂
• Radian (rad) ○◂

Units: Solid Angle

• Steradian (sr) ○◂

GNU

Applications & Domain-Specific Languages

• GNU Octave ○›

Compilers

• ❪𖣐₃ⱼₐ’❫ GNU Compiler Collection ○

GNU Compiler Collection & C Compilers

• GCC ○›

GNU Compiler Collection & C++ Compilers

• G++ ○›

GNU Compiler Collection & Fortran Compilers

• GFortran ○›

GNU Debuggers

• GNU Debugger (GDB) ○›

GNU Shells: Bourne Shell

• Bash ○›

Libraries: C Libraries

• glibc ○›

Utilities & File Formats

• gzip ○›

Graphics

{offcase}

• Ray Tracing ○𓆪ᴳᴿᴬᴾᴴᴵꟲˢ

Classes & Classes

• Plot ○꠹

Common

• 3D Computer Graphics ○
• Raster Graphics ○
• Vector Graphics ○

Statistical Classes

• Scatter Plot ○꠹

High-Energy Astrophysics

{signature}

• Effective Area ○◂ᴴᴱᴬ
• Event ○꠹ᴴᴱᴬ
• Image ○꠹ᴴᴱᴬ
• Light Curve ○꠹ᴴᴱᴬ
• Point Spread Function ○◂ᴴᴱᴬ
• Spectrum ○꠹ᴴᴱᴬ

{tbd}

• Disk Fraction (f) ○◂
• RMS Amplitude of QPO (a) ○◂
• RMS Power of PDS (r) ○◂

{toc}

• CIAO ○›
• HEASoft ○›

ACIS

• Continuous Clocking Mode ○

Channel Error =

• Channel Error (σ₍I₎≈√C₍I₎) ○￩

Chi-Squared =

• Chi-Squared (χ²=Σ₍C₍I₎-Cₚ₍I₎₎²∕σ₍I₎²) ○￩ᴴᴱᴬ

Classes

• Hardness-Intensity Diagram (HID) ○꠹
• Response Matrix ○꠹

Classes of High-Energy Astrophysics Data

• Events List ○꠹
• Source List ○꠹

Classes of X-Ray Binaries

• High-Mass X-Ray Binary (HMXB) ○꠹
• Low-Mass X-Ray Binary (LMXB) ○꠹
• X-Ray Burster ○꠹

Classes of X-Ray Binaries: Low-Mass X-Ray Binary

• Z Source ○꠹

Classes of X-Ray Binaries: Quasar

• Microquasar ○꠹

Common

• Event Grade ○
• Pileup ○
• Quasi-Periodic Oscillation (QPO) ○
• Spectral Hardening ○

diskbb-norm =

• diskbb-norm (₍R𝘪𝘯∕D₁₀₎²cos₍i₎) ○￩

Domains

• Gamma-Ray Astronomy ○𓆪
• X-Ray Astronomy ○𓆪

File Formats

• ARF ○˒
• PHA ○˒
• PI ○˒
• RMF ○˒

Functions

• Instrumental Response (R₍I,E₎) ○◂
• Model Spectrum (f₍E, p1, p2, …₎) ○◂
• Source Spectrum (f₍E₎) ○◂

Gamma-Ray Observatories

• Compton GRO ○´
• Fermi ○´

Hardness Ratio =

• Hardness Ratio (HR=₍C₂-C₁₎∕₍C₂+C₁₎) ○￩

HEASoft

• XSELECT ○›
• XSTAR ○›

HMXB

• 4U 1543−475 ❍
• A0620-00 ❍
• Cygnus X-1 ❍
• Cygnus X-3 ❍
• GRO J0422+32 ❍
• GRO J1655−40 ❍
• GRS 1009-45 ❍
• GRS 1124-683 ❍
• GRS 1915+105 ❍
• GS 1354-64 ❍
• GS 2000+25 ❍
• GX 339-4 ❍
• H 1705-25 ❍
• LMC X-1 ❍
• LMC X-3 ❍
• M33 X-7 ❍
• Swift J1727.8-1613 ❍
• V404 Cygni ❍
• V4641 Sagittarii ❍
• XTE J1118+480 ❍
• XTE J1550−564 ❍
• XTE J1650−500 ❍
• XTE J1859+226 ❍

Hubs

• CALDB ○➛
• Chandra Source Catalog (CSC) ○➛
• HEASARC ○➛

Instrumentation

• ❪𖣐₂’❫ X-Ray Detectors ○

LMXB

• Hercules X-1 ❍
• MAXI J1820+070 ❍
• Swift J1753.5-0127 ❍

Mass Function =

• Mass Function (f₍M₎≡P𝘰𝘳𝘣K₂³∕2πG=M₁sin³i∕₍1+q₎²) ○￩

Mass Ratio =

• Mass Ratio (q≡M₂∕M₁) ○￩

Math Sets

• Good Time Interval (GTI) ○◂

Observed Counts =

• Observed Counts (C₍I₎=∫f₍E₎⋅R₍I,E₎⋅dE) ○￩

Particulars

• Lynx ○˒

Photon Counts

• Observed Counts (C₍I₎) ○◂
• Predicted Counts (Cₚ₍I₎) ○◂

Quantities

• ❪𝛿’❫⁺ Spectral Fitting Parameters ○
• Channel Error (σ₍I₎) ○◂
• Count Rate ○◂
• Hardness Ratio ○◂
• Instrument Channel (I) ○◂
• Mass Ratio (q) ○◂
• Photon Counts (C) ○◂
• Viscosity Parameter (α) ○◂

Quasi-Periodic Oscillation

• High-Frequency QPO (HFQPO) ○
• Low-Frequency QPO (LFQPO) ○

Sets

• ❪◑❫ X-Ray States ○

Software

• ❪𖣐₃’❫ Spectral Fitting Packages ○️

Software: IXPE

• ixpeobssim ○›

Units

• Crab ○◂

X-Ray Binaries

• ❪◑❫ HMXB ○
• ❪◑❫ LMXB ○

X-Ray Detectors: Chandra

• ACIS ○´
• HRC ○´

X-Ray Detectors: NuSTAR

• FPMA ○´
• FPMB ○´

X-Ray Detectors: RXTE

• All-Sky Monitor (ASM) ○´
• Proportional Counter Array (PCA) ○´

X-Ray Detectors: Swift

• BAT ○´
• XRT ○´

X-Ray Detectors: XMM-Newton

• EPIC ○´

X-Ray Detectors: XPoSat

• XSPECT ○´

X-Ray Observatories

• Ariel 5 ○´
• ASCA ○´
• BeppoSAX ○´
• Chandra ○´
• EXOSAT ○´
• Ginga ○´
• Granat ○´
• IXPE ○´
• MAXI ○´
• NICER ○´
• NuSTAR ○´
• RXTE ○´
• Swift ○´
• Uhuru ○´
• XMM-Newton ○´
• XPoSat ○´
• XRISM ○´

X-Ray States

• ❪◑❫ Intermediate States ○
• Hard State ○
• Quiescent State ○
• Soft State ○
• Steep Power Law State ○

XRT

• Photon Counting Mode ○
• Windowed Timing Mode ○

HTML

JavaScript Libraries

• rehype ○›

Information

Classes

• Archive ○꠹
• Language ○꠹

Common

• Information Retrieval ○
• Publishing ○
• Readability ○️

Domains

• Coding Theory ○𓆪
• Information Science ○𓆪
• Information Theory ○𓆪

Language

• Natural Language ○꠹

Instrumentation

Classes of High-Energy Astrophysics Instrumentation

• Gas Counter ○꠹
• Proportional Counter ○꠹

Common

• Photon Counting ○

Internet

Domain Name System

• Resource Record (RR) ○˒

Internet Protocol Suite

• Domain Name System (DNS) ○˒
• File Transfer Protocol (FTP) ○˒
• HTTP ○˒
• Internet Message Access Protocol (IMAP) ○˒
• MIME ○˒
• Post Office Protocol (POP) ○˒
• Secure Sockets Layer (SSL) ○˒
• SSH ○˒

Internet Protocol Suite: HTTP

• HTTPS ○˒

Internet Protocol Suite: Secure Sockets Layer

• Transport Layer Security (TLS) ○˒

MIME

• MIME Type ○꠹

Resource Record

• CNAME Record ○˒

Standards

• ❪◑❫ Internet Protocol Suite ○

Java

Software

• Java ○›

Software: Java

• Java Development Kit (JDK) ○›
• Java Runtime Environment (JRE) ○›

JavaScript

{toc}

• Bun ○›
• Node.js ○›

Classes & String Interpolation

• Template Literal ○꠹

JavaScript Bundlers

• esbuild ○›
• tsup ○›

Libraries

• Luxon ○›
• Moment.js ○›
• PDF-LIB ○›
• PDF.js ○›

Particulars

• CommonJS ○˒
• v8 ○›

LaTeX

Hubs

• CTAN ○➛
• Overleaf ○➛

Particulars

• BibTeX ○›

Linear Algebra

{float}

• Minor ○◂

Classes of Spaces

• Column Space ○
• Null Space ○꠹
• Row Space ○

Common

• Eigenvalue ○
• Eigenvector ○
• Linear Combination ○
• Linear Independence ○
• Linear Span ○
• Rank ○
• Row Echelon Form ○
• Trace ○

Hamming Codes

• Hamming(7,4) ○◂

Linear Codes

• ❪∂₂’❫ Hamming Codes ○

Recipes

• ❪∂₂’❫ Linear Codes ○
• Gaussian Elimination ○◂

Linux

{toc}

• APT ○›

Linux File Systems

• ext4 ○˒

Standards

• Network Block Device (NBD) ○˒

Logic

{signature}

• Absorption ○ᴸᴼᴳᴵꟲ
• Completeness ○ᴸᴼᴳᴵꟲ
• Literal ○꠹ᴸᴼᴳᴵꟲ
• Simplification ○ᴸᴼᴳᴵꟲ

Classes

• Boolean ○꠹

Logical Connectives

• Conjunction (AND) ○◂
• Disjunction (OR) ○◂
• Negation (NOT) ○◂
• Non-Disjunction (NOR) ○◂
• Sheffer Stroke (NAND) ○◂

Logical Connectives: Disjunction

• Exclusive Disjunction (XOR) ○◂

Logical Connectives: Non-Disjunction

• Exclusive Non-Disjunction (XNOR) ○◂

Operations

• ❪∂₁ₐ’❫ Logical Connectives ○

Quantities

• False ❍
• True ❍

Loose

{float}

• ❪◑❫ Graphing Calculators ○
• ❪◑❫ Scientific Calculators ○
• ISO 8601 ○˒

{loose}

• TI-Nspire ○´

Machine Learning

{float}

• TensorFlow ○›

{signature}

• Transformer ○ᴹᴸ

{toc}

• PyTorch ○›

Chatbots

• ChatGPT ○˒
• Claude ○˒

Classes

• Autoencoder ○꠹
• Large Language Model ○꠹

Common

• Artificial Intelligence ○
• Dimensionality Reduction ○
• Hyperparameter Optimization ○
• Principal Component Analysis ○

Neural Network

• Recurrent Neural Network ○꠹

Sets

• ❪◑❫ Chatbots ○

Magnetism

Quantities: Electromagnetic Field

• Magnetic Field ○◂

Quantities: Flux

• Magnetic Flux ○◂

Markdown

{toc}

• Obsidian ○›

JavaScript Libraries

• remark ○›

Utilities

• Quartz ○›

Mathematics

{signature}

• Parameter ○꠹ᴹᴼᴰᴱᴸ

{tbd}

• Statement ○꠹

{toc}

• Arithmetic ○𓆪
• Binary (n₂) ○
• Combinatorics ○𓆪
• Function ○꠹
• Matrix ○꠹
• Vector ○꠹

Classes

• Algorithm ○꠹
• Canonical Form ○꠹
• Coefficient ○꠹
• Constant ○꠹
• Contour Line ○꠹
• Equation ○꠹
• Expression ○꠹
• Formula ○꠹
• Graph ○꠹
• Identity ○꠹
• Identity Element ○꠹
• Inequality ○꠹
• Law ○꠹
• Mathematical Object ○꠹
• Mathematical Structure ○꠹
• Model ○꠹
• Multiplicative Inverse ○꠹
• Numeral System ○꠹
• Operator ○꠹
• Polynomial ○꠹
• Quantity ○꠹
• Sum ○꠹
• Theorem ○꠹
• Time Series ○꠹
• Value ○꠹
• Variable ○꠹

Classes of Functions

• Binary Function ○꠹
• Gaussian Function ○꠹
• Identity Function ○꠹
• Inverse Function ○꠹
• Involution ○꠹
• Loss Function ○꠹
• Mapping ○꠹
• Monotonic Function ○꠹
• Operation ○꠹
• Periodic Function ○꠹
• Transformation ○꠹
• Unary Function ○꠹

Classes of Functions: Quadratic

• Quadratic Function ○꠹

Classes of Matrices

• Augmented Matrix ○꠹
• Elementary Matrix ○꠹
• Identity Matrix ○꠹
• Inverse Matrix ○꠹
• Square Matrix ○꠹
• Transformation Matrix ○꠹
• Zero Matrix ○꠹

Classes of Matrices: Coefficient

• Coefficient Matrix ○꠹

Classes of Matrices: Square Matrix

• Triangular Matrix ○꠹

Classes of Matrices: Transformation Matrix

• Rotation Matrix ○꠹

Classes of Numbers

• Complex Number ○꠹
• Fraction ○꠹
• Imaginary Number ○꠹
• Integer ○꠹
• Negative Number ○꠹
• Positive Number ○꠹
• Real Number ○꠹

Classes of Operations

• Binary Operation ○꠹
• Unary Operation ○꠹

Classes of Polynomials

• Binomial ○꠹
• Quadratic ○꠹

Classes of Sets

• Index Set ○꠹
• Interval ○꠹
• Space ○꠹

Classes of Spaces: Parameter

• Parameter Space ○꠹

Classes of Spaces: Vector

• Vector Space ○꠹

Common

• Abscissa ○
• Approximation ○
• Calculation ○
• Computation ○
• Equality ○
• Order of Operations ○
• Ordinate ○
• Positional Notation ○
• Radix ○
• Rounding ○
• Sign ○
• Simplification ○
• Truncation ○

Constants

• Euler’s Number (e) ❍
• Imaginary Unit (i) ❍
• Pi (π) ❍

Domains

• Numerical Analysis ○𓆪
• Optimization ○𓆪

Equation

• Linear Equation ○꠹
• Parametric Equation ○꠹
• System of Equations ○꠹

Geometric Classes

• Euclidean Vector ○꠹
• Geometric Transformation ○꠹

Infinities

• Infinity (∞) ○◂

Integers

• -1 ❍
• 0 ❍
• 1 ❍
• 10 ❍
• 16 ❍
• 2 ❍
• 8 ❍

Linear Classes

• Linear Transformation ○꠹

Math

• ❪∂’❫ Symbols ○

Numbers

• ❪𝛿₁’❫ Integers ○

Numeral Systems

• Decimal (n₁₀) ○
• Hexadecimal (n₁₆) ○
• Octal (n₈) ○

Operations

• ❪∈₁’❫ Sequence Operations ○

Sequence Operations: Addition

• Summation (Σ) ○◂

Sequence Operations: Multiplication

• Sequence Multiplication (∏) ○◂

Sets

• ❪◑❫ Numeral Systems ○

System of Equations & Linear Classes

• System of Linear Equations ○꠹

Types

• Number ○꠹
• Scalar ○꠹
• Sequence ○꠹
• Set ○꠹
• Tensor ○꠹
• Tuple ○꠹

Matrix

Operations

• Matrix Exponential ○◂
• Transpose ○◂

Mechanics

{toc}

• Rotation ○

Common

• Mass Distribution ○

Force =

• Force (F=m⋅a) ○￩

Quantities

• Acceleration (a) ○◂
• Force (F) ○◂
• Momentum (p) ○◂
• Pressure (p) ○◂
• Speed (v) ○◂
• Velocity (v) ○◂
• Weight (W) ○◂
• Work (W) ○◂

Quantities & Quantities

• Displacement (s) ○◂

Velocity

• Radial Velocity ○◂

Work =

• Work (W=F⋅s) ○￩

Memory

{toc}

• Memory Address ○

Common

• Memory Management ○

Methodology

Classes

• Best Practice ○꠹

Common

• Heuristics ○
• Simulation ○

Domains

• Design ○𓆪

Metrology

{toc}

• Instrumentation ○𓆪

Calibration

• Cross-Calibration ○

Classes

• Unit ○꠹

Common

• Accuracy ○
• Calibration ○
• Precision ○
• Significand ○
• Significant Figures ○
• Unit Conversion ○

Domains

• Telemetry ○𓆪

Sets

• ❪◑❫ Metric Prefixes ○

Standards

• ❪◑❫ Systems of Measurement ○

Systems of Measurement

• CGS Units ○˒
• International System of Units (SI) ○˒
• MKS Units ○˒

Network

Classes

• Communication Protocol ○꠹

Classes & {toc}

• Computer Network ○꠹

Domains

• Network Theory ○𓆪

Networks

Classes & Classes

• Neural Network ○꠹

Node.js

{toc}

• npm ○›

Utilities

• nvm ○›

Obsidian

{offcase}

• Homepage ○›ᴼᴮˢᴵᴰᴵᴬᴺ

{toc}

• Dataview ○›
• DataviewJS ○˒
• Templater ○›

Plugins

• AlphaBullet ○›
• BRAT ○›
• Dataview Serializer ○›

Operating System

{offcase}

• Kernel ○꠹ᴼˢ

{signature}

• Event ○꠹ꟲᴼᴹᴾ
• Sandbox ○ᴼˢ

Classes

• Access Token ○꠹
• Access-Control List (ACL) ○꠹
• Application Binary Interface (ABI) ○꠹
• Command-Line Interface (CLI) ○꠹
• Driver ○꠹
• Graphical User Interface (GUI) ○꠹
• Lock ○꠹
• Process ○꠹
• Symbolic Link ○꠹
• System Call (syscall) ○꠹
• System Resource ○꠹
• Thread ○꠹

Classes & {toc}

• File System ○꠹

Classes of File Systems

• Hierarchical File System ○꠹
• Journaling File System ○꠹

Classes of Software

• Shell ○꠹

Common

• Clipboard ○
• Focus ○
• Inter-Process Communication (IPC) ○
• Privilege ○
• Scheduling ○
• Superuser ○

Process

• Child Process ○꠹

Standards & Standards

• ❪◑❫ File Systems ○

Orbit

Quantities

• Orbital Inclination (i) ○◂

Quantities: Period

• Orbital Period (P𝘰𝘳𝘣) ○◂

Quantities: Rotational Frequency

• Orbital Frequency ○◂

Photometry

Quantities

• Luminous Intensity (Iᵥ) ○◂

Quantities: Flux

• Luminous Flux (Φᵥ) ○◂

Physics

{float}

• Phase Shift ○

{offcase}

• Coherence ○ᴾᴴʸˢ

Classes

• Particle ○꠹
• Physical Field ○꠹
• Physical Object ○꠹
• Physical Quantity ○꠹
• Redshift ○꠹
• Wave ○꠹

Classes & Classes

• Cycle ○꠹

Classes of Constants

• Physical Constant ○꠹

Classes of Radiation: Blackbody & Thermal Radiation

• Blackbody Radiation ○꠹

Classes of Radiation: Spectroscopic Classes

• Gamma Ray ○꠹
• X-Ray ○꠹

Classes of Radiation: Synchrotron & Relativistic Classes

• Synchrotron Radiation ○꠹

Common

• Attenuation ○
• Diffraction ○
• Frame of Reference ○
• Radiation ○
• Reflection ○

Common & Common

• Dimension ○
• Distance ○
• Flux ○
• Oscillation ○
• Resonance ○

Constants

• Gravitational Constant (G) ❍
• Speed of Light (c) ❍

Continuum Mechanics Classes

• Fluid ○꠹

Continuum Mechanics Sets

• ❪◑❫ Fluids ○

Diffraction & {float}

• Diffraction Grating ○꠹

Electromagnetic Classes

• Electromagnetic Radiation ○꠹

Gravity & Relativistic Classes

• Gravitational Wave ○꠹

Methods

• Ray Tracing ○𓆪

Parameter & Resonance

• Parametric Resonance ○

Particle

• Particle Accelerator ○꠹

Particle Accelerator

• Synchrotron ○꠹

Physical Dimensions

• Length (l) ○◂

Quantities

• ❪𝛿’❫⁺ Physical Dimensions ○
• Density (ρ) ○◂
• Energy (E) ○◂
• Frequency (f) ○◂
• Period ○◂
• Power (P) ○◂

Quantities & Quantities

• Area (A) ○◂
• Volume (V) ○◂

Quantities: Area & Density

• Area Density (ρ𝐴) ○◂

Quantities: Physical Dimensions

• Mass (m) ○◂

Radiation & Pressure

• Radiation Pressure ○◂

Relativistic Concepts

• Relativistic Reflection ○

Sets

• ❪◑❫ Fundamental Forces ○

Space & Relativistic Concepts

• Spacetime ○

Thermodynamic Classes

• Thermal Radiation ○꠹

Units of Energy

• Electronvolt (eV) ○◂
• Erg ○◂
• Joule (J) ○◂

Units of Length

• Meter (m) ○◂

Units of Mass

• Dalton ○◂

Wave

• Soliton ○꠹

Polarimetry

Common

• Plane of Polarization ○

Quantities

• ❪𝛿’❫ Stokes Parameters ○

Probability

Chi-Squared Distribution & Hypothesis Test

• Chi-Squared Test ○꠹

Classes

• Cumulative Distribution Function (CDF) ○꠹
• Moment Generating Function (MGF) ○꠹
• Probability Density Function (PDF) ○꠹
• Probability Distribution ○꠹
• Probability Mass Function (PMF) ○꠹
• Random Variable ○꠹

Domains

• Bayesian Probability ○𓆪
• Frequentist Probability ○𓆪

Exponential Distribution =

• Exponential Distribution (Exp₍β₎=₍1∕β₎⋅exp₍-x∕β₎) ○￩
• Exponential Distribution (Exp₍λ₎=λ⋅exp₍-λx₎) ○￩

Functions

• ❪∂₁’❫ Probability Distributions ○
• Likelihood (p₍X┃θ₎) ○◂
• Marginal Likelihood (p₍X₎) ○◂
• Posterior (p₍θ┃X₎) ○◂
• Prior (p₍θ₎) ○◂

Methods

• Bayesian Inference ○𓆪
• Frequentist Inference ○𓆪

Posterior =

• Posterior (p₍θ┃X₎=p₍X┃θ₎⋅p₍θ₎∕p₍X₎) ○￩
• Posterior (p₍θ┃X₎∝p₍X┃θ₎⋅p₍θ₎) ○￩

Probability

• Conditional Probability ○

Probability Distributions

• Bernoulli Distribution (Bernoulli₍p₎) ○◂
• Beta Distribution (Beta₍α,β₎) ○◂
• Binomial Distribution (B₍n,p₎) ○◂
• Cauchy Distribution ○◂
• Gamma Distribution (Gamma₍α,β₎) ○◂
• Geometric Distribution (Geom₍p₎) ○◂
• Hypergeometric Distribution (Hypergeom₍N,K,n₎) ○◂
• Inverse Gamma Distribution (InvGamma₍α,β₎) ○◂
• Negative Binomial Distribution (NB₍r,p₎) ○◂
• Normal Distribution (N₍μ,σ²₎) ○◂
• Poisson Distribution (Pois₍λ₎) ○◂
• Uniform Distribution (U⦋a,b⦌) ○◂

Probability Distributions: Gamma Distribution

• Chi-Squared Distribution (χ²₍k₎) ○◂
• Exponential Distribution (Exp₍λ₎) ○◂

Rules

• Bayes’ Theorem ○◂

Programming

{alias}

• C＃ ○˒

{signature}

• Array ○꠹ᴾᴿᴳᴿᴹ
• Boolean ○꠹ᴾᴿᴳᴿᴹ
• Class ○꠹ᴾᴿᴳᴿᴹ
• Constant ○꠹ᴾᴿᴳᴿᴹ
• Date ○꠹ᴾᴿᴳᴿᴹ
• Expression ○꠹ᴾᴿᴳᴿᴹ
• Function ○꠹ᴾᴿᴳᴿᴹ
• Identity ○ᴾᴿᴳᴿᴹ
• Literal ○꠹ᴾᴿᴳᴿᴹ
• Map ○◂ᴾᴿᴳᴿᴹ
• Method ○꠹ᴾᴿᴳᴿᴹ
• Number ○꠹ᴾᴿᴳᴿᴹ
• Object ○꠹ᴾᴿᴳᴿᴹ
• Operation ○꠹ᴾᴿᴳᴿᴹ
• Operator ○꠹ᴾᴿᴳᴿᴹ
• Parameter ○꠹ᴾᴿᴳᴿᴹ
• Property ○꠹ᴾᴿᴳᴿᴹ
• Scalar ○꠹ᴾᴿᴳᴿᴹ
• Set ○꠹ᴾᴿᴳᴿᴹ
• Statement ○꠹ᴾᴿᴳᴿᴹ
• Tuple ○꠹ᴾᴿᴳᴿᴹ
• Value ○꠹ᴾᴿᴳᴿᴹ
• Variable ○꠹ᴾᴿᴳᴿᴹ

{toc}

• C ○˒
• C++ ○˒
• CSS ○˒
• Fortran ○˒
• HTML ○˒
• JavaScript ○˒
• Lua ○˒
• Markdown ○˒
• Python ○͒
• R ○˒
• VS Code ○›
• YAML ○˒

Applications

• ❪𖣐₃ₐ’❫ IDEs ○

Architectural Classes

• Branch Predictor ○꠹

Assignment

• Parallel Assignment ○

Class

• Inner Class ○꠹

Classes

• Application Programming Interface (API) ○꠹
• Attribute ○꠹
• Block ○꠹
• Branch ○꠹
• Breakpoint ○꠹
• Command ○꠹
• Comment ○꠹
• Data Type ○꠹
• Delimiter ○꠹
• Docstring ○꠹
• Escape Sequence ○꠹
• Generator ○꠹
• Identifier ○꠹
• Include Directive ○꠹
• Instance ○꠹
• Integrated Development Environment (IDE) ○꠹
• Label ○꠹
• Library ○꠹
• Loop ○꠹
• Macro ○꠹
• Mask ○꠹
• Metasyntactic Variable ○꠹
• Name-Value Pair ○꠹
• Pointer ○꠹
• Read-Eval-Print Loop (REPL) ○꠹
• Reference ○꠹
• Regular Expression (Regex) ○꠹
• Runtime System ○꠹
• Stack Trace ○꠹
• Standard Streams ○꠹
• Translator ○꠹
• Wildcard ○꠹

Classes & Translator

• Assembler ○꠹
• Compiler ○꠹
• Interpreter ○꠹

Classes of Algorithms

• In-Place Algorithm ○꠹
• Sorting Algorithm ○꠹

Classes of Programmatic Functions

• Anonymous Function ○꠹
• Constructor ○꠹
• Function Object ○꠹
• Hash Function ○꠹
• User-Defined Function ○꠹
• Wrapper Function ○꠹

Classes of Programmatic Functions: Wrapper Function

• Helper Function ○꠹

Classes of Programmatic Objects

• Callable Object ○꠹
• File Object ○꠹
• Immutable Object ○꠹

Classes of Programmatic Operations

• Bitwise Operation ○꠹

Classes of Programmatic Operations: String

• String Operation ○️꠹

Classes of Programmatic Statements

• Conditional ○꠹
• Return Statement ○꠹

Classes of Programming Languages

• Domain-Specific Language ○꠹
• General-Purpose Programming Language ○꠹
• High-Level Programming Language ○꠹
• Low-Level Programming Language ○꠹

Classes of Programming Languages: High-Level Programming Language

• Scripting Language ○꠹

Classes of Programming Languages: Low-Level Programming Language

• Assembly Language ○꠹

Classes of Software

• Package Manager ○꠹

Classes of Spaces

• Namespace ○꠹

Common

• Aliasing ○
• Assignment ○
• Code Completion ○
• Command History ○
• Comparison ○
• Concatenation ○
• Control Flow ○
• Coupling ○
• Debugging ○
• Documentation ○
• Evaluation ○
• Exception Handling ○
• Find and Replace ○
• Foobar ○
• Garbage ○
• Globbing ○
• Iteration ○
• Just-In-Time Compilation ○
• Lint ○
• Logging ○
• Name Binding ○
• Name Collision ○
• Pretty Printing ○
• Programming Style ○
• Pseudocode ○
• Recursion ○
• Refactoring ○
• Scope ○
• Semantics ○
• Serialization ○
• Syntax ○
• Typing ○
• Vectorization ○

Computer Engineering Classes

• Stack Machine ○꠹

Computer Engineering Sets

• ❪◑❫ Assembly Languages ○

Data Types

• Collection ○꠹
• Container ○꠹
• List ○꠹
• Priority Queue ○꠹
• Stack ○꠹
• String ○꠹

Data Types: {signature}

• Integer ○꠹ᴾᴿᴳᴿᴹ

Data Types: Array

• Associative Array ○꠹

Data Types: Associative Array

• Dictionary ○꠹

Data Types: Number

• Floating-Point Number (Float) ○꠹

Data Types: Priority Queue

• Heap ○꠹

Debugging

• Debugger ○꠹
• Debugging Information ○

Domain-Specific Languages

• ❪◑❫ Query Languages ○
• S ○˒

Domains

• Modular Programming ○𓆪
• Object-Oriented Programming ○𓆪

Evaluation

• Lazy Evaluation ○

File Formats: Markup Languages & {toc}

• SVG ○˒

Function

• Function Overloading ○
• Function Prototype ○꠹

Garbage

• Garbage Collection ○

General-Purpose Languages

• Ada ○˒
• Go ○˒
• Java ○˒
• Julia ○˒
• Lisp ○˒
• Perl ○˒
• Rust ○˒
• Tcl ○˒

General-Purpose Languages: {toc}

• TypeScript ○˒

General-Purpose Languages: C

• ❪◑❫ C-Family Languages ○

Global Scope & Variable

• Global Variable ○꠹

Hardware Description Languages

• VHDL ○˒

Hubs

• GitHub ○➛

Hubs: {float}

• Stack Overflow ○➛

Library

• Shared Library ○꠹
• Standard Library ○꠹
• Static Library ○꠹

List

• List Comprehension ○

Literal

• String Literal ○꠹

Local Scope & Variable

• Local Variable ○꠹

Loop

• For Loop ○꠹
• While Loop ○꠹

Markup Languages

• ❪◑❫ Style Sheet Languages ○

Markup Languages & {toc}

• XML ○˒

Markup Languages: Typesetting Systems & {toc}

• LaTeX ○›

Markup Languages: XML & HTML

• XHTML ○˒

Object

• Object Composition ○
• Object Copying ○
• Object Lifetime ○

Object Copying

• Deep Copy ○
• Shallow Copy ○

Operations: Array

• Array Slicing ○◂

Programming Languages

• ❪◑❫ Domain-Specific Languages ○
• ❪◑❫ General-Purpose Languages ○

Query Languages

• SQL ○˒

Reference

• Handle ○꠹

Scope

• Global Scope ○
• Local Scope ○

Semantics

• Static Semantics ○

Stack

• Call Stack ○꠹
• Stack Underflow ○

Stack & Overflow

• Stack Overflow ○

String

• Empty String ○
• String Interpolation ○

Style Sheet Languages: {toc}

• Sass ○˒

Python

{offcase}

• argparse ○›ᴾʸ
• builtins ○›ᴾʸ
• collections ○›ᴾʸ
• copy ○›ᴾʸ
• csv ○›ᴾʸ
• dataclasses ○›ᴾʸ
• datetime ○›ᴾʸ
• enum ○›ᴾʸ
• getpass ○›ᴾʸ
• glob ○›ᴾʸ
• hashlib ○›ᴾʸ
• io ○›ᴾʸ
• itertools ○›ᴾʸ
• json ○›ᴾʸ
• logging ○›ᴾʸ
• math ○›ᴾʸ
• operator ○›ᴾʸ
• os ○›ᴾʸ
• pathlib ○›ᴾʸ
• pickle ○›ᴾʸ
• platform ○›ᴾʸ
• pprint ○›ᴾʸ
• re ○›ᴾʸ
• shutil ○›ᴾʸ
• signal ○›ᴾʸ
• site ○›ᴾʸ
• sqlite3 ○›ᴾʸ
• string ○›ᴾʸ
• subprocess ○›ᴾʸ
• sys ○›ᴾʸ
• textwrap ○›ᴾʸ
• threading ○›ᴾʸ
• time ○›ᴾʸ
• traceback ○›ᴾʸ
• typing ○›ᴾʸ
• unittest ○›ᴾʸ
• urllib ○›ᴾʸ
• venv ○›ᴾʸ

{toc}

• Beautiful Soup ○›
• dateutil ○›
• dotenv ○›
• Matplotlib ○›
• NumPy ○›
• pandas ○›
• pip ○›
• Python Standard Library ○›
• Requests ○›
• SciPy ○›

Classes & String Interpolation

• f-string ○꠹

Hubs

• PyPI ○➛
• Python.org ○➛

Libraries: {float}

• Boto3 ○›

Libraries: {toc}

• PyMuPDF ○›

Organizations

• Python Packaging Authority (PyPA) ○˒

Python Interpreters

• CPython ○›

Python JIT Compilers

• PyPy ○›

Quantum Mechanics

Classes

• Axion ○꠹

Common

• Bremsstrahlung ○
• Compton Scattering ○
• Observer Effect ○
• Pair Production ○

Compton Scattering

• Inverse Compton Scattering ○

Elementary Particles & Bosons

• ❪◑❫ Gauge Bosons ○

Elementary Particles & Fermions

• ❪◑❫ Leptons ○

Fermions & Subatomic Particles

• Neutron ❍
• Proton ❍

Gauge Bosons

• Photon ❍

Leptons

• Neutrino ❍

Leptons & Subatomic Particles

• Electron ❍

Quantities

• Photon Energy (E) ○◂

Sets

• ❪◑❫ Subatomic Particles ○

Spectral Fitting Parameters

• Electron Temperature ○◂

Subatomic Particles

• ❪◑❫ Bosons ○
• ❪◑❫ Elementary Particles ○
• ❪◑❫ Fermions ○

Radiometry

{toc}

• Photometry ○𓆪

Quantities

• Albedo ○◂
• Intensity ○◂
• Luminosity (L) ○◂
• Radiance ○◂
• Radiant Energy (Qₑ) ○◂

Quantities: Flux

• Radiant Flux (Φₑ) ○◂

Relativity

Common

• Coordinate Time ○

Dimensionless Spin =

• Dimensionless Spin (a∗=a∕R𝘨) ○￩

Domains

• General Relativity ○𓆪
• Special Relativity ○𓆪

Gravitational Radius =

• Gravitational Radius (R𝘨≡GM∕c²) ○￩

High-Energy Astrophysics Concepts

• Innermost Stable Circular Orbit (ISCO) ○

ISCO Radius =

• ISCO Radius (R𝘪𝘴𝘤𝘰=6R𝘨) ○￩

Quantities

• Black Hole Angular Momentum (J) ○◂
• Gravitational Radius (R𝘨) ○◂
• ISCO Radius (R𝘪𝘴𝘤𝘰) ○◂
• Lorentz Factor ○◂
• Schwarzschild Radius (R𝘴) ○◂
• Spin (a) ○◂

Rules

• No-Hair Theorem ○◂

Schwarzschild Radius =

• Schwarzschild Radius (R𝘴=2R𝘨) ○￩

Spectral Fitting Parameters

• Dimensionless Spin (a∗) ○◂

Spin =

• Spin (a=J∕cM) ○￩

Structures

• Kerr Metric ○◂
• Schwarzschild Metric ○◂

Rotation

Quantities: Force

• Torque (τ) ○◂

Quantities: Frequency

• Angular Frequency (ω) ○◂
• Rotational Frequency (ν) ○◂

Quantities: Momentum

• Angular Momentum (L) ○◂

Set Theory

Classes

• Indexed Family ○꠹
• Partition ○꠹

Common

• Complement ○
• Counting ○
• Enumeration ○

Operations

• Union ○◂

Signal Processing

{offcase}

• Coherence ○ˢᴵᴳᴺᴬᴸ

Classes

• Analog Signal ○꠹
• Digital Signal ○꠹

Common

• Noise ○
• Sampling ○

Sets

• ❪◑❫ Waveforms ○

Signal & Noise

• Signal-to-Noise ○

Waveforms

• Sawtooth Wave ○꠹
• Square Wave ○꠹

Waveforms: Sine

• Sine Wave ○꠹

Software Engineering

{offcase}

• Pipeline ○꠹ˢᵂᴱ
• Sandbox ○ˢᵂᴱ

{toc}

• Git ○›

Classes

• Design Pattern ○꠹
• Repository ○꠹

Common

• Unit Testing ○
• Version Control ○

Software: Version Control

• ❪𖣐₃’❫ Version Control Systems ○

Spectral Fitting

{float}

• PyXSPEC ○›

{signature}

• Chi-Squared (χ²) ○◂ᴴᴱᴬ

{toc}

• Spectral Fitting ○𓆪

Sets

• ❪◑❫ Spectral Fitting Models ○

Spectral Fitting Normalization Parameters: diskbb

• diskbb-norm ○◂

Spectral Fitting Normalization Parameters: gauss

• gauss-norm (K) ○◂

Spectral Fitting Normalization Parameters: Nthcomp

• nthcomp-norm ○◂

Spectral Fitting Normalization Parameters: powerlaw

• powerlaw-norm (K) ○◂

Spectral Fitting Normalization Parameters: simpl

• Scattered Fraction (f𝘴𝘤) ○◂

Spectral Fitting Packages

• ISIS ○›
• SPEX ○›

Spectral Fitting Packages: {toc}

• XSPEC ○›

Spectral Fitting Packages: CIAO

• Sherpa ○›

Spectral Fitting Parameters

• ❪𝛿’❫ Spectral Fitting Normalization Parameters ○
• Inner-Disk Radius (R𝘪𝘯) ○◂
• Inner-Disk Temperature (T𝘪𝘯) ○◂
• Line Energy (E𝘭) ○◂
• Line Width (σ) ○◂
• Mass Accretion Rate (M˙) ○◂
• Photon Index (Γ) ○◂

Spectral Fitting Parameters: Spectral Hardening

• Spectral Hardening Factor (f𝘤𝘰𝘭) ○◂

Spectral Fitting Statistics

• Cash Statistic ○◂

Spectroscopy

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• Color ○

Classes

• Spectral Line ○꠹
• Spectrum ○꠹

Colors

• Black ○
• White ○

Common

• Spectral Broadening ○

High-Energy Astrophysics Concepts

• Fe Kα Line ○

Sets

• ❪◑❫ Colors ○

X-Ray

• Hard X-Ray ○꠹
• Soft X-Ray ○꠹

State

Classes

• Finite-State Machine ○꠹
• State Diagram ○꠹

Common

• Hysteresis ○

Statistics

{offcase}

• Collinearity ○ˢᵀᴬᵀˢ
• Error ○꠹ˢᵀᴬᵀˢ
• Kernel ○ˢᵀᴬᵀˢ

Chi-Squared

• Reduced Chi-Squared (χᵥ²) ○◂

Classes

• Confidence Interval ○꠹
• Hypothesis Test ○꠹
• Markov Chain ○꠹
• Mean ○꠹
• Monte Carlo Method ○꠹
• Percentage ○꠹
• Power Law ○꠹
• Quantile ○꠹
• Residual ○꠹
• Statistic ○꠹

Classes of Constants

• Normalizing Constant ○꠹

Classes of Functions

• Window Function ○꠹

Classes of Matrices

• Covariance Matrix ○꠹
• Scatterplot Matrix ○꠹

Common

• Correlation ○
• Covariance ○
• Estimation ○
• Fisher Information ○
• Goodness of Fit ○
• Normalization ○
• Null Hypothesis ○
• Significance ○
• Uncertainty ○
• Weighting ○

Correlation

• Autocorrelation ○

Correlation & Coefficient

• Correlation Coefficient ○꠹

Markov Chain & Classes of Algorithms

• Markov Chain Monte Carlo (MCMC) ○꠹

Mean

• Weighted Mean ○꠹

Quantile & Normalization

• Quantile Normalization ○

Quantities

• ❪𝛿’❫ Statistics ○
• Degrees of Freedom ○◂
• Root Mean Square ○◂
• Standard Deviation (σ) ○◂
• Variance (σ²) ○◂

Statistic

• Test Statistic ○꠹

Statistics: Chi-Squared Distribution

• Chi-Squared (χ²) ○◂

Statistics: Correlation Coefficient

• Pearson’s r ○◂

Statistics: Pearson’s r

• Spearman’s ρ ○◂

System

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• State ○

Common

• Feedback ○
• Scalability ○

Thermodynamics

Classes

• Blackbody ○꠹

Physical Dimensions

• Temperature (T) ○◂

Time

Classes

• Calendar ○꠹
• Clock ○꠹
• Date ○꠹
• Day ○꠹
• Timer ○꠹

Physical Dimensions

• Time (t) ○◂

Trigonometry

Classes

• Trigonometric Function ○꠹

Functions

• Cosine (cos₍x₎) ○◂
• Sine (sin₍x₎) ○◂

TypeScript

Particulars

• tsc ○›

Typography

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• TeX ○›

Classes

• Newline ○꠹
• Ruby Character ○꠹

Common

• Letter Case ○
• Subscript ○
• Superscript ○

Letter Case

• Camel Case ○
• Kebab Case ○
• Snake Case ○

Software

• ❪𖣐₃’❫ Typesetting Systems ○

Unix

Classes

• File Descriptor ○꠹
• Inode ○꠹

Classes & {offcase}

• Pipeline ○꠹ᵁᴺᴵˣ
• Signal ○꠹ᵁᴺᴵˣ

Classes of Unix Files

• Device File ○꠹

Classes of Unix Files: Hidden File

• Dotfile ○꠹

Common

• Unix Filesystem ○

Standards

• Filesystem Hierarchy Standard (FHS) ○˒
• POSIX ○˒

Unix Shells

• Bourne Shell (sh) ○›
• C Shell (csh) ○›
• Z Shell (zsh) ○›

Unix Shells: C Shell

• tcsh ○›

Utilities & File Formats

• tar ○›

URL

Classes

• Clean URL ○꠹
• Slug ○꠹

Vector

Operations

• Dot Product ○◂

VS Code

Plugins

• Edit CSV ○›
• Rainbow CSV ○›
• Ruff ○›

Windows

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• I∕O Completion Port ○꠹
• I∕O Request Packet (IRP) ○꠹

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• Chocolatey ○›
• winget ○›
• WSL ○›

Classes

• Security Descriptor ○꠹
• Security Identifier (SID) ○꠹

Classes & Shared Library

• Windows Shared Library ○꠹

Classes of Windows Files

• Batch File ○꠹
• Windows System File ○꠹

File Formats

• VHD ○˒

File Formats: VHD

• VHDX ○˒

Hubs

• Sysinternals ○➛

Particulars

• Alternate Data Stream (ADS) ○˒
• Component Object Model (COM) ○˒
• File Explorer ○›
• Mandatory Integrity Control (MIC) ○˒
• Mark of the Web ○˒
• Task Scheduler ○›
• Windows API ○˒
• Windows Registry ○˒

Utilities: Sysinternals

• Process Explorer ○›
• Process Monitor ○›

Windows API

• Windows Native API ○˒

Windows Debuggers

• WinDbg ○›

Windows File Systems

• FAT ○˒
• NTFS ○˒

Windows Shared Library

• Dynamic-Link Library (DLL) ○˒

Windows Shells

• Command Prompt ○›
• PowerShell ○›

Windows Versions

• Windows 11 ○›
• Windows 2000 ○›
• Windows NT ○›
• Windows Server 2003 ○›
• Windows XP ○›

Windows Versions: Windows NT

• Windows NT 4.0 ○›

WSL

Particulars

• wslu ○›

XML

Particulars

• XPointer ○˒

Zotero

Plugins

• Better Notes ○›

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