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About

A collection of tidbits on things I learn

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Contents

There are #445 articles

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Categories

• Algorithm
• ARM
• Astronomy
• Assembler
• Books
• Build Tools
• Code Art
• Computer Architecture
• Computer Science Research
• Containers
• Crypto
• Data
• Data Structure
• Design
• Digital Design
• DSP
• Filesystem
• Frontend
• Git
• GNU
• GNU Plot
• Graphics
• HPC
• Ideas
• IRC
• Kernel
• Languages
• LLM
• Math
• Network
• Notebooks
• Origami
• Papers
• Philosophy
• Posix
• Platforms
• Postgresql
• Psychology
• Quantum
• RFC
• SIMD
• Sqlite
• Tools
• Unix
• Vim
• Web

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Algorithm

• Boyer–Moore algorithm
• Boyer–Moore–Horspool algorithm
• XOR Shift Rotate
• Kadane
• Chaitin-Briggs coloring
• Chow’s priority coloring
• Bresenham’s line algorithm
• Cooley–Tukey FFT Algorithm

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ARM

General Purpose ARM Devices

• Apple M1

Embedded ARM Based Devices

• Raspberry PI
• PI Boot Config

ARM Thumb

• ARM Thumb

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Astronomy

• Jansky(Jy)
• uv plane
• TaQL
• ephemerides
• Astronomical unit
• Fanaroff Riley Classification

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Assembler

CPU Instruction Sets

• x86
• ARM

Other ISAs

• PTX

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Books

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Build Tools

Makefile

• Makefile
• Makefile Auto Variables
• Make foreach
• Make parallel builds
• Make reading shell output
• Make string functions
• Echoing commands
• Include other makefile

CMake

• CMake Fetch
• CMake Dependency
• CMake Release Type
• CMake Flags per Release
• CMake Specify Compiler

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Code Art

• Code Art Secrets
• Avatar Generator
• Glider

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Computer Architecture

• CPU Features
• Branch Prediction
• Resident Set Size
• Cache Coherence
• Sandy Bridge Pipeline

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Computer Science Research

• Sorting Networks
• Vectorizing Complex Multiplication
• Z3 Theorm Prover

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Containers

• Using perf within containers
• Docker prevent permission issue with files created inside container

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Crypto

• Constant time cryptography
• Hashcash

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Data

• k means
• Quantization
• CNN
• RNN
• Fine tuning

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Data Structure

• Disjoint Set
• Segment Tree

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Design

• Covariance and Contravariance
• Law of Demeter.md

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Digital Design

Bus

• AXI
• Wishbone
• Getting started
• Verilog
• HLS
• AXI Stream
• LUT
• PCI-Express
• DDR
• JTAG
• Litex
• OpenOCD
• Memory Controller
• NoC
• GTKWave
• Open Hardware
• OpenOCD Chipyard
• Decoupling
• Differential Signalling
• KiCad
• Power On Reset
• Sync and Async Reset
• DDR
• Bambu HLS
• 8b10b encoding
• Formal Verification
• DFI Controller
• MIG 7 series

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DSP

• Random Signals
• Filters

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Frontend

React

• React Froward Ref

Core Web

• Request Animation Frame

Core CSS

• Flex Box
• Bounding Client Rectangle
• Before After Pseudo Elements
• Linear Gradient
• Multiclass Selectors
• CSS Matrix Transforms

Frontend Tools

• Emmet Abbreviations

  CSS Tricks

• Pure CSS Triangles

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Filesystem

• FAT Filesystem

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Git

• Co authoring Commits
• Update branch with upstream
• Check out a PR
• Create patch from commits
• Delete git submodule
• Git bisect
• Git tag types
• Git submodule Update
• Git force update detection

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GNU

• dejagnu
• gperf
• recutils
• texinfo

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GNUPlot

• gnuplot color theme
• gnuplot output terminals
• gnuplot fitting

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Graphics

• Three JS
• Creating a trapezoid
• OBJ format
• Wavefunction Collapse
• Signed Distance Function

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IRC

• IRC Cheatsheet
• IRC Relay

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Ideas

• sqlite t-digest
• busybox httpd

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Kernel

• namespaces
• sched_yield
• menuconfig
• vfs

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Languages

Bash

• Bash Check if env variable present
• Bash getopts
• Bash params
• Bash pass env variable to subcommand
• Bash read config file and store value from config file
• Bash get script directory
• Bash subcommand
• Bash convert to upper case
• Bash check platform
• Bash declare
• Bash array
• Bash for loop
• Bash auto completions

C

• Function as Argument with function pointer
• Optargs for cli arg parsing
• Setting OpenSSL in Makefile
• Default Argument
• Static Method
• CWeb

CPP

• Initializer List
• Copy Constructor
• Move Contructor
• Trailing Return Type
• auto and decltype
• Remove Reference
• const member function
• vectors
• Run-Time Type Information
• Rule of Five and One
• C++ Modules
• C++ override ostream
• Likely Attribute
• Inline

Fortran

• GPU Fortran

Go

• Using C Libraries in Go
• Using Go Libraries in C
• Compiling Go for ARM

Perl

• Read line by line
• Perl run modes

Python

• Closing plots in matplotlib
• Downloading from Google Collab
• Fault handler

Tex

• MathJax

Typescript

• Typescript Conditional Typing

Java

• JAR Packing Java

JS

• Yarn Berry
• Convert from hex to UTF-8 in Node
• Incresing libuv Thread pool

Guile

• Guile Assoc List
• Guile CLI Application
• Guile Macros

OCaml

• OCaml Learning Resources

HPC

• Domain Decomposition
• GPU Acceleration
• OpenMP
• ASIC
• FPGA
• Cuda
• Optimizing x86 code
• LLVM MCA
• MPI Bindings
• CUDA Direct
• Thrust

Generic

• Data structure alignment
• Backpressure in Streams
• BLAS
• ABI
• Alias Analysis
• Bitwise Tricks

C/CPP Compilers

• What is dSYM
• Ignore unused var in C/C++
• Creating a Shared Library
• Include Guards in C
• Setup for LLDB
• Pragma once
• restrict
• File as Flag
• Frame Pointer
• Compilation Flags
• Auto Vectorization
• Compact Unwinding
• DWARF
• Stack Unwinding
• Common Subexpression Elimination
• IRA algorithm
• Loop Distribution
• Profile Guided Optimization
• Output ASM
• Pragmas in define
• Struct Packing
• Inline ASM
• Offloading PTX
• AVX
• POD
• C Compiler fast math
• C Compiler FORTIFY_SOURCE
• Cost of integer division
• FFTW libraries
• Offloading
• CPP Dialect

GCC Specific

• GCC specific auto vectorization features
• Tree SSA
• Function Multiversioning

Clang Specific

LLVM

• LLVM passes
• LLVM tools
• LLVM IR

Clang

• Clang specific auto vectorization features
• Clang specific flags
• clangd compile options
• Range constraint of Multiplication and Division
• Clang time trace

MLIR

• Dialects
• Filecheck
• Tablegen

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LLM

• Embedding
• Vector Stores
• LLM
• LLM Glue Benchmark
• LLM for TDD

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Math

Automata

• Abelian Sandpile
• Game of Life

Category Theory

• Category Theory
• Catesian Closed Categories
• Curry Howard Isomorphism

Engineering Math

Fractals

• Chaos Game
• Iterated Function Systems

Geometry

• Rhombile Tiling
• Stellation
• Affine Transform
• 3D Rotation

Linear Algebra

• Normal Equations
• Einstein Notation
• Penrose Notation

Number Theory

• Ortho Latin Square
• Perlin Noise
• Kummer’s Theorm
• Wilson’s Theorm
• Pisano period
• Zeckendorf’s Theorm
• De Bruijn sequence
• Chinese remainder theorem
• Euler’s theorm
• Euler’s totient function
• Farey Sequence
• Stern Brocot Tree
• Extended Euclidean Algorithm
• Euclidean Algorithm
• Prime Number Theorm
• Mobius Function
• Chakravala Method
• Fibonnaci Matrix

Statistics

• Kuiper Test
• Chi-squared test
• Kullback Leibler Divergence

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Network

• Gopher Protocol
• Data URL
• Preflight Request
• WSDL
• CGI Interface

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Notebooks

• CASA Imaging
• Visualising FFT
• Normal Equations
• Searching the Sky
• Sky Coordinates
• Measurement Set
• 2D Guassian Fitting
• Understanding W-Sampling
• Reading FITS Header cfitsio
• Reading FITS Header astropy
• WCS
• Understanding Random Forest
• Power Spectral Density
• R2C FFT, C2C FFT, IFFT through FFT
• Analysing Linear Polarisation
• Exploring MSv4

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Origami

Units

• Litte Unit
• Nick Robinson’s Trimodule
• Oxi Unit
• Sonobe Unit
• TSU Unit

Cubes

• Gyroscope

Intersectional planes

• XYZ

Fractals

• Menger Sponge

Icosahedron

• Gallery
• Sonobe Icosahedron
• Trimodule Icosahedron

Tesslations

• Clover Tesslation
• Square Interlace Tesslation

Spiral

• Navel Shell

Curlicue

• Curlicue

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Papers

• The Design and Implementation of FFTW3
• Source Finding
• H1 21cm Absorption
• MG-J0414+0534

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Philosophy

• Mu
• Absurdism
• Existentialism

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POSIX

• regex

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Physics

• Barycenter
• Radial Velocity

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Psychology

• Pygmalion Effect

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Platforms

DOS

• Setting PATH in DOS
• Job File Table
• COM file defaults
• Check for input

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Postgresql

Postgresql

• pg_ctl
• Template Databases
• Explain on sort
• Explain on Join
• Extended Statistics
• Trust Authentication

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Quantum

• cnot gate
• entanglement
• quantum-circuit
• qubit
• quantum teleportation
• toffoli gates

Notebooks

• Bell State
• Full Adder
• GHZ State
• W State

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RFC

• RFC 1122 Communication Layer
• RFC 7578 multipart/form-data
• RFC 2068 HTTP/1.1
• RFC 2616 HTTP/1.1
• RFC 7807 Problem Details in HTTP API

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SIMD

• Intrinsics reference
• Intrinsics Learning Resources and Blogs

x86

• AVX Cmp
• SSE2
• AVX512

Neon

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Sqlite

• Execute Single Query In Sqlite Cli
• Change default separator
• Output Queries to File
• sqlite import csv
• Run script on sqlite DB

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Tools

apr

• apr

ab

• Apache Benchmark

apropos

• apropos

Clang Format

• Clang Format

convert

• Resize Image with Convert
• Tint Image with Convert

cURL

• cURL POST
• cURL Format

  dc

• DC Calculator

dd

• dd

Dracula

• Dracula

ffmpeg

• Convert Video format with ffmpeg

gpg

• gpg

hexdump

• Hexdump

i3

• i3wm

imagemagik

• mogrify compress image

jot

• jot

locate

• locate

Lynx

• Lynx Print HTML

m4

• m4

nm

• nm

nmap

• Scanning local network IPs with NMap

otool

• otool

pactl

• pactl

perf

• perf

pkg-config

• pkg-config

ppm

• ppm

rlwrap

• rlwrap

rs

• rs

seq

• seq

snap

• snap

tar

• tar

tmux

• tmux copy pane content
• tmux rename window

wget

• wget

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Unicode

• Block elements
• Box drawing
• Dingbat
• Geometric Shapes
• Mathematical Operations

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Unix

• ar
• Cron
• Difference between glibc and libc6
• Difference between guneabi vs gnueabihf
• SSH Identity
• Systemd
• xargs
• Generate Locale
• Changing Ownership
• Setting path of dynamic libraries
• Change Shell
• Understanding Wifi
• Ansi Colors
• Users and Groups
• Shebang
• IO Uring
• SSH key creation and sharing
• Static IP in local network
• Mach O
• tid and pid
• Cpu Info
• SSH Disable password login
• shm
• sshfs
• Energy Consumption
• Protection rings
• List devices
• Reading Serial Port
• Ghost Script
• TFPT
• Kernel Modules
• Codesign

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Vim

• How to exit vim
• Vim packages
• Find and Replace
• Visual Mode
• Copy To Clipboard in MacOS
• Paste From Clipboard in MacOS
• Vim marks
• Replace and Change

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Web

• Standard SubResource Integrity - SSRI

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Credits

Inspired by

• yoshuawuyts
• jbranchaud

You can find other similar repos in RichardLitt’s meta-knowledge list