Core Wiki

angular

Anonymous (anonymous@undisclosed.example.com) — 2019-10-04T12:52:05+0000

Angular CLI Commands Generate module/service/component ng g m path/NAME --routing ng g s path/NAME --module=path/NAME2 ng g c path/NAME --module=path/NAME2 Building dist with/without hashing ng build --prod --build-optimizer ng build --prod --build-optimizer --output-hashing=all

apache

Anonymous (anonymous@undisclosed.example.com) — 2020-01-27T11:31:24+0000

Apache .htaccess Redirect requests to https RewriteEngine on RewriteCond %{HTTPS} !=on RewriteRule ^/?(.*) https://%{SERVER_NAME}/$1 [R,L] Rewrite domain.com/index.php?page=X routes as domain.com/X RewriteEngine on RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule (.*) index.php?page=$1 [QSA]

articles

Anonymous (anonymous@undisclosed.example.com) — 2020-03-14T18:22:39+0000

Articles Articles/videos Domain Driven Design (DDD) * Code design should be understandable to non developers * Communicate design in the code * Types are for type checking and as domain modelling tool (“a good static type system is like having a compile-time unit tests

aws

Anonymous (anonymous@undisclosed.example.com) — 2020-03-22T11:28:40+0000

Server Management Resources * Github, AWS S3, CloudFront purge pipeline * AWS Load Balancer, SSL, EC2 Create and Mount external volume Mount a volume xvdf to folder /newvolume lsblk sudo mkfs -t ext4 /dev/xvdf sudo mkdir /newvolume sudo mount /dev/xvdf /newvolume/ pm2 Starting node server with pm2 sudo npm install pm2 -g pm2 start npm -- start pm2 status

chinese

Anonymous (anonymous@undisclosed.example.com) — 2020-03-08T20:04:32+0000

Chinese Mandarin beautiful - 美丽 (mei li）[mei vi] charming - 迷人 (miren) good morning - 早上好 (zǎo shàng hǎo) good night - 晚安 (Wan an) good night cutie - 晚安, 小可爱 (wan an xiao ke ai) [wan an shio ke ai] haha - 哈哈 (haha)

css

Anonymous (anonymous@undisclosed.example.com) — 2020-03-27T11:37:31+0000

/* shortcut */ justify-content: flex-start | flex-end | center | space-between | space-around | space-evenly | start | end | left | right ... + safe | unsafe; align-items: stretch | flex-start | flex-end | center | baseline | first baseline | last baseline | start | end | self-start | self-end + ... sa…

data_structures

Anonymous (anonymous@undisclosed.example.com) — 2020-03-08T09:44:59+0000

Data Structures Big O * Finding all subsets of a set O(2^n) * Finding all permutations of a string O(n!) * Binary search O(log n) * Sorting using mergesort O(n log(n)) * Iterating over all cells of a matrix (m,n) O(m*n) Linked Lists Singly Linked List time complexities

dgraph

Anonymous (anonymous@undisclosed.example.com) — 2020-04-01T12:47:47+0000

Dgraph References * Dgraph docs Terminology Mutation - adding/removing data Mutation formats * RDF (Resource Description Framework) * JSON (JavaScript Object Notation) Mutation paterns * blank UID reference <_:michael> * explicit UID reference

golang

Anonymous (anonymous@undisclosed.example.com) — 2020-04-02T06:58:39+0000

Golang General * Docs * Effective Go * String formating CLI go build hello.go go run hello.go go mod init example.com/user/hello #creating module go install example.com/user/hello # builds executable hello and installs in $HOME/go/bin/hello export PATH=$PATH:$(dirname $(go list -f '{{.Target}}' .)) # appending path, we can now call ''hello'' go clean -modcache # remove all downloaded modules go test # runs unit tests for *_test.go files go test ./platform/newsfeed go test ./...

ios

Anonymous (anonymous@undisclosed.example.com) — 2020-04-02T20:23:01+0000

UI Toolkit References * Official UIKit * xCode 11 with no storyboard Controllers * UINavigationController Snippets UICollectionViewCell - element inside a controller (can be a friend entry in whatsapp/messenger) class FriendCell: UICollectionViewCell { override init(frame: CGRect) { super.init(frame: frame) setupViews() } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } func setupViews() { …

javascript

Anonymous (anonymous@undisclosed.example.com) — 2020-03-13T13:17:46+0000

Javascript References * Utility types Popular code styles * Airbnb * Standard * Google Functional aspects find Function find() returns the first value of an array satisfying a given condition. let array1 = [1,4,6,8,12]; let found = array1.find(el => { return el > 10 } ); //found = 12

keras

Anonymous (anonymous@undisclosed.example.com) — 2019-11-10T17:31:24+0000

Keras MNIST example import tensorflow as tf mnist = tf.keras.datasets.mnist (x_train, y_train), (x_test, y_test) = mnist.load_data() x_train, x_test = x_train / 255.0, x_test / 255.0 model = tf.keras.models.Sequential([ tf.keras.layers.Flatten(input_shape=(28, 28)), tf.keras.layers.Dense(128, activation='relu'), tf.keras.layers.Dense(10, activation='softmax') ]) model.compile(optimizer='adam', loss='sparse_categorical_crossentropy', metrics=['accuracy']) …

machine_learning_todo

Anonymous (anonymous@undisclosed.example.com) — 2020-03-01T11:07:23+0000

Machine Learning Insights / Concepts * 1710.05381 Regarding performance of different methods for addressing imbalance, in almost all of the situations oversampling emerged as the best method * 1506.02640 You Only Look Once: Unified, Real-Time Object Detection (Original YOLO paper)

mathematica

Anonymous (anonymous@undisclosed.example.com) — 2020-02-14T13:14:28+0000

Mathematica Functional aspects Equivalent ways to apply function f to every element of the list {a,b,c} Map[f, {a, b, c}] f[#]&/@{a, b, c} Plotting Options Fonts LabelStyle -> {FontFamily -> "FONT_NAME", SIZE, COLOR} LabelStyle -> {FontFamily -> "Roboto Condensed Light", 18, GrayLevel[0]}

node

Anonymous (anonymous@undisclosed.example.com) — 2019-11-27T09:51:20+0000

node Useful packages dotenv

php

Anonymous (anonymous@undisclosed.example.com) — 2020-01-07T08:01:06+0000

PHP URL Rewrite with GET variables In order to rewrite links such as domain.com?one=var1&two=var2 into domain.com/var1/var2 with Apache, set .htaccess file to RewriteEngine On RewriteBase / RewriteEngine On Options All -Indexes RewriteBase /directoryname/ RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^(.*)$ index.php?url=$1 [QSA,L]

python

Anonymous (anonymous@undisclosed.example.com) — 2020-03-24T09:07:16+0000

Python Virtual environment Creating and sourcing python virtual environment virtualenv NAME source NAME/bin/activate which python To deactivate deactivate Functional Equivalent ways of filtering a list list(filter(lambda n: n % 2 == 0, range(10))) [n for n in range(10) if n % 2 == 0]

pytorch

Anonymous (anonymous@undisclosed.example.com) — 2020-03-15T18:19:18+0000

Pytorch Standard Imports import torch import torch.nn as nn import torch.nn.functional as F Tensor data type Depending on the construction tensor data could be copied or shared in memory data = np.array([1,2,3]) t1 = torch.Tensor(data) t2 = torch.tensor(data) t3 = torch.as_tensor(data) t4 = torch.from_numpy(data) data[0] = 0 data[1] = 0 data[2] = 0 print(t1) # [1,2,3] print(t2) # [1,2,3] print(t3) # [0,0,0] print(t4) # [0,0,0]

react

Anonymous (anonymous@undisclosed.example.com) — 2020-03-18T09:34:26+0000

React References * React-Typescript cheatsheet Starter commands yarn create react-app projectName --template typescript yarn add node-sass react-router-dom @types/react-router-dom @types/react-dom .htaccess RewriteEngine On RewriteBase / RewriteRule ^index\.html$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.html [L]

ros

Anonymous (anonymous@undisclosed.example.com) — 2019-11-04T16:20:27+0000

ROS Basic commands To work with ROS one needs to source the environmental setup source /opt/ros/melodic/setup.zsh rospack find NAME rospack find roscpp roscd NAME roscd turtle rosls NAME rosls turtle rospack depends NAME rospack depends1 NAME rospack depends1 rospy

rust

Anonymous (anonymous@undisclosed.example.com) — 2020-03-15T20:59:31+0000

Rust Resources * Half an hour to learn Rust * Rust Cheat Sheet General Rust uses snake case convention: * functions and variables all lower case with _ separating words * function parenthesis after function name Printing data structures is possible using annotations #[derive(Debug)] struct Rectangle { width: u32, height: u32, } let rect1 = Rectangle { width: 30, height: 30, }; println!("{:?}", rect1); // inline println!("{:#?}", rect1); // multiline

scraping

Anonymous (anonymous@undisclosed.example.com) — 2020-02-28T09:55:08+0000

Scraping Dynamic class names If class names change to subCategory_ import re from bs4 import BeautifulSoup base_url = "https://trustpilot.com" def get_soup(url): return BeautifulSoup(requests.get(url).content, 'lxml') data = {} soup = get_soup(base_url + '/categories') for category in soup.findAll('div', {'class': re.compile('subCategory___')}): name = category.find('h3', {'class': re.compile('subCategoryHeader___')}).text name = name.strip() data[name] = {} sub_…

shell

Anonymous (anonymous@undisclosed.example.com) — 2022-10-16T08:33:25+0000

Shell commands Download file with curl curl https://norvig.com/big.txt --output big.txt curl -O -J https://norvig.com/big.txt Call the same route 100 times curl http://localhost:3000/transactions/populate\?\[1-100\] curl file upload curl http://localhost:3000/inventory -F "file=@warhol.jpg" -vvv

ssl

Anonymous (anonymous@undisclosed.example.com) — 2020-01-15T11:56:47+0000

SSL Certificates Let's Encrypt Generating Let's Encrypt private key and certificate. sudo apt-get install certbot certbot certonly --manual This will ask to create a file in location ./.well-known/acmechallenge/FileNameString. The file has to be accessed over http to verify owner of the domain. To do so create a server in the root directory to access the file at required path.

start

Anonymous (anonymous@undisclosed.example.com) — 2020-04-03T12:32:40+0000

Development * Go * Javascript * Mathematica * Python * PHP * Rust * Swift * Shell commands Front End * Angular * React * CSS * iOS * Swift UI Machine Learning * Keras * Pytorch * Knowledge Docs, Software & Tools * Apache * Articles * Data Structures * Dgraph * ROS * Server Management * SSL Certificates Languages * Chinese

swift

Anonymous (anonymous@undisclosed.example.com) — 2020-04-13T10:02:02+0000

Swift References * Swift Docs * let guard vs let if In Swift structs are value types whereas classes are reference types. When you copy a struct, you end up with two unique copies of the data. When you copy a class, you end up with two references to one instance of the data. It's a crucial difference, and it affects your choice between classes or structs.

swiftui

Anonymous (anonymous@undisclosed.example.com) — 2020-04-14T11:19:08+0000

Swift UI References * Move screen on Keyboard entry * Accessing view geometry * State, ObservedObject, EnvironmentObject * iOS Design guidelines * Tips and Tricks * Search Bar * UserDefaults Customisation * TabView * BottomBar animated API To enable networking add to plist.info: App Transport Security Settings and inside of it Allow Arbitrary Loads Navigation View Dynamic list generation NavigationView { List { ForEach(categories.keys.sorted(), id: \.self)…