Luke Meyers metric-space

High-Performance Matrix Multiplication

This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).

Intro

Matrix multiplication is a mathematical operation that defines the product of

Joining CSV Tables in Haskell

This article describes a technique for joining (in an SQL-style) lists of haskell data structures.

Maybe not the fastest, maybe not the smartest, but it works.

Why I like it

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.

Effective Engineer - Notes

By Edmond Lau
Highly Recommended 👍
http://www.theeffectiveengineer.com/

What's an Effective Engineer?

prologue

Why another tutorial? Because there are other tutorials which write a server - client or maybe a client client where they have only two clients, maybe by hardcoding ips.

<rant>
  What annoys me more is, that there are 100's of same tutroials on the internet, 
 that just works for a given scenario, but guess what, I don't fucking care what works

There's a couple of ways, one way is

Get search results
- Do SPC / and type in your search string
- or SPC x S and search string - where x is your scope indicator (p for project, d for directory, etc..)
Once you have the occurences you want, hit C-c C-e inside the helm buffer to put all your match occurences and puts them into a special buffer called the edit buffer or something like that
in that buffer you can use any commands you'd normally use on a buffer
the C-c C-c to commit your changes.

	{-# LANGUAGE Arrows #-}
	{-# LANGUAGE ConstraintKinds #-}
	{-# LANGUAGE FlexibleContexts #-}
	{-# LANGUAGE FlexibleInstances #-}
	{-# LANGUAGE GADTs #-}
	{-# LANGUAGE InstanceSigs #-}
	{-# LANGUAGE LambdaCase #-}
	{-# LANGUAGE MultiParamTypeClasses #-}
	{-# LANGUAGE RankNTypes #-}
	{-# LANGUAGE ScopedTypeVariables #-}

	{-# LANGUAGE DataKinds, TypeFamilies, TypeOperators, GADTs,
	ScopedTypeVariables, TypeOperators #-}

	-- \| Type-level natural numbers and singletons, with proofs of
	-- a few basic properties.

	module BasicNat (
	-- \| Type-level natural numbers
	Nat (..)
	, type (+)

	module Main

	import Data.Vect

	-- %hide transpose

	dot : Num a => Vect n a -> Vect n a -> a
	dot va vb = foldr (+) 0 $ zipWith (*) va vb

	Matrix : (rows : Nat) -> (cols : Nat) -> Type -> Type

	//
	// Copyright 2015 Google Inc. All Rights Reserved.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software

	{-# LANGUAGE TypeSynonymInstances #-}

	import Data.Monoid
	import Data.Maybe

	-- How much water does a "histogram" hold?
	--
	-- Inspired by Guy Steele's talk "Four Solutions to a Trivial Problem"
	-- https://www.youtube.com/watch?v=ftcIcn8AmSY