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<manifest>
    <!-- Request legacy Bluetooth permissions on older devices. -->
    <uses-permission android:name="android.permission.BLUETOOTH"
                     android:maxSdkVersion="30" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"
                     android:maxSdkVersion="30" />

    <!-- Needed only if your app looks for Bluetooth devices.
         You must add an attribute to this permission, or declare the
         ACCESS_FINE_LOCATION permission, depending on the results when you

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########## Install NGINX ##############

# Install software-properties-common package to give us add-apt-repository package
sudo apt-get install -y software-properties-common

# Install latest nginx version from community maintained ppa
sudo add-apt-repository ppa:nginx/stable

# Update packages after adding ppa

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// Sample: download json as excel file (BOM + utf-16le encoding)
// reference: 
// https://gist.github.com/maciejjankowski/2db91642fb9eaa771111f2c0538e4560
// 
<script>
function JSON2CSV(objArray) {
    var array = typeof objArray != 'object' ? JSON.parse(objArray) : objArray;
    var str = '';
    var line = '';
    // header

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const admin = require("admin");
function getFirebaseUser(req, res, next) {
  console.log("Check if request is authorized with Firebase ID token");

  if (
    !req.headers.authorization ||
    !req.headers.authorization.startsWith("Bearer ")
  ) {
    console.error(
      "No Firebase ID token was passed as a Bearer token in the Authorization header.",

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// 1. add a executable dev.sh to run your script (example: web.js)
#!/bin/bash
node --inspect web.js

// 2. install foreman
$ npm install -g foreman

// 3. prepare your environment variables file
$ touch .env

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// Google Play API Key
// ref: http://stackoverflow.com/questions/35127086/android-inapp-purchase-receipt-validation-google-play
// ref: https://developers.google.com/android-publisher/authorization
// ref: http://google.github.io/google-api-nodejs-client/18.0.0/index.html#toc14__anchor
//
// install npm package
// ref: https://github.com/google/google-api-nodejs-client
// $ npm install googleapis --save
//
const google = require('googleapis');

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Coursera course
https://www.coursera.org/learn/machine-learning

Week 1 Note:
Partial derivative in gradient descent for two variables
https://math.stackexchange.com/questions/70728/partial-derivative-in-gradient-descent-for-two-variables/189792#189792

Gradient descent
https://www.youtube.com/watch?v=WnqQrPNYz5Q&ab_channel=AlexanderIhler

jeffhuangtw

// resend verify email
Parse.Cloud.define("ResendVerifyEmail", function(request, response) {
    var user = Parse.User.current();
    if (!user) {
        response.error("INVALID_USER");
        return;
    }
    var email = request.params.email;
    var query = new Parse.Query(Parse.User);
    Parse.Cloud.useMasterKey();

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var queryAllUser = new Parse.Query(Parse.User);
Parse.Cloud.useMasterKey();
queryAllUser.each(function(user) {
  var queryMatch = new Parse.Query(Parse.User);
  queryMatch.containedIn("offer", user.get("search"));
  return query.find().then(function(users) {
    if (users.length >0) {
      var targetList = [];
      for (i = 0; i < users.length; i++) {
        var userPointer =  Parse.Object.extend(Parse.User);

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Parse.Cloud.define("TestUpload", function(request, response) {
    var attachmentURLs = [];
    attachmentURLs.push({'name': 'gogole_logo', 'url': 'https://www.google.com.tw/intl/en_ALL/images/srpr/logo11w.png', 'content-type': 'image/png'});
    attachmentURLs.push({'name': 'yahoo_logo', 'url': 'https://www.google.com.tw/images/nav_logo225.png', 'content-type': 'image/png'});

    var promises = [];
    attachmentURLs.forEach(function(file){
        promises.push(Parse.Cloud.httpRequest({
            url: file.url,
          }).then(function(fetchedFile){