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Weka is a collection of machine learning algorithms for data mining tasks. The algorithms can either be applied directly to a dataset or called from your own Java code. Weka contains tools for data pre-processing, classification, regression, clustering, association rules, and visualization. It is al...

Let's say there's a collection called Todos and the autopublish package is added. Here is the basic component. import { createContainer } from 'meteor/react-meteor-data'; import React, { Component, PropTypes } from 'react'; import Todos from '/imports/collections/Todos'; export class List exte...

If your application is going to run on different devices, it's going to need to render to different ViewPorts, based on the device size. You can deal with this in two ways: with javascript rules, or CSS media styles. If you've been using a MVC or MVVM library, such as Angular or Ember (or Blaze, for...

Before you compile your app and run it on your device, you'll need create some icons and splash screens, and add a mobile-config.js file to your app. App.icons({ // iOS 'iphone': 'resources/icons/icon-60x60.png', 'iphone_2x': 'resources/icons/[email protected]', 'ipad': 'resources/icons...

You'll need to separate out your application layer from your database layer, and that means specifying the MONGO_URL. Which means running your app through the bundle command, uncompressing it, setting environment variables, and then launching the project as a node app. Here's how... #make sure you...

Then go into the mongo shell and initiate the replica set, like so: mongo > rs.initiate() PRIMARY> rs.add("mongo-a") PRIMARY> rs.add("mongo-b") PRIMARY> rs.add("mongo-c") PRIMARY> rs.setReadPref('secondaryPreferred')

The replica set will need an oplog user to access the database. mongo PRIMARY> use admin PRIMARY> db.addUser({user:"oplogger",pwd:"YOUR_PASSWORD",roles:[],otherDBRoles:{local:["read"]}}); PRIMARY> show users

The --url flag can be tricky to use. There is a 60 second window to authenticate, and then the username/password randomly resets. So be sure to have robomongo open and ready to configure a new connection when you run the command. # get the MONGO_URL string for your app meteor mongo --url $METEOR...

Run meteor, open another terminal window, and run the following command. mongoexport --db meteor --collection foo --port 3001 --out foo.json

Importing into a default Meteor instance is fairly easy. Note that you can add a --jsonArray option if your json file is exported as an array from another system. mongoimport --db meteor --port 3001 --collection foo --file foo.json

Preallocation. Mongo sets aside disk-space in empty containers, so when the time comes to write something to disk, it doesn't have to shuffle bits out of the way first. It does so by a doubling algorithm, always doubling the amount of disk space preallocated until it reaches 2GB; and then each preal...

Did you know about the --url flag? Very handy. meteor mongo --url YOURSITE.meteor.com

They're not easily accessible. If you run the 'meteor bundle' command, you can generate a tar.gz file, and then run your app manually. Doing that, you should be able to access the mongo logs... probably in the .meteor/db directory. If you really need to access mongodb log files, set up a regular mo...

Gotta rotate those log files, or they'll eventually eat up all of your disk space. Start with some research... mongodb-log-file-growth rotate-log-files Log files can be viewed with the following command... ls /var/log/mongodb/ But to set up log-file rotation, you'll need to do the following.....

db.posts.find().forEach(function(doc){ db.posts.update({_id: doc._id}, {$set:{'version':'v1.0'}}, false, true); });

db.posts.find().forEach(function(doc){ if(doc.arrayOfObjects){ // the false, true at the end refers to $upsert, and $multi, respectively db.accounts.update({_id: doc._id}, {$unset: {'arrayOfObjects': "" }}, false, true); } });

db.originalName.renameCollection("newName" );

With the power of regex comes great responsibility.... db.posts.find({'text': /.*foo.*|.*bar.*/i})

db.posts.find().forEach(function(doc){ if(doc.commentsBlobId){ var commentsBlob = db.comments.findOne({'_id': commentsBlobId }); db.posts.update({_id: doc._id}, {$set:{'comments': commentsBlob }}, false, true); } });

db.posts.find().forEach(function(doc){ if(doc.foo === 'bar'){ db.posts.update({_id: doc._id}, {$set:{'foo':'squee'}}, false, true); } });