#fun stuff

Learning to learn to use Linux can be challenging, as everything from its reputation to general look can be intimidating. Having never used it before, instead using Windows both at home and for school I always saw Linux as something that was in the realm of true veteran software engineers and computer programmers.

During my first few weeks at Setfive I’ve had the chance to begin learning Linux and I have found it to be a useful and powerful tool. After learning some common and not so common commands I’ve really started to appreciate the flexibility and ease of use of the command line.

Here are 10 easy Linux “one liners” that allow us to accomplish some everyday tasks in a simple and efficient manner.

1. Sort a file

$ sort myfile.txt

This will sort the given file in numerical and alphabetical order:

Here a file, num, is being sorted alphanumerically, resulting in a sorted list.

2. Delete duplicate lines within a file

$ sort myfile.txt | uniq

This small addition to the sort command will not only sort the file but will remove any duplicates found within the file:

Here we can see the same num file being sorted, however this time the duplicates are being removed leaving us only with 1 of each entry.

3. Convert .mp3 and .wav files

$ ffmpeg -i input.mp3 output.wav

With this example we convert an .mp3 file to a .wav file, and it can be done the other way as well converting .wav to .mp3.

$ ffmpeg -i input.wav output.mp3

4. Recursively creating a directory structure

$ mkdir -p new/directory/structure/example

Using mkdir we are able to create subdirectories, however with the -p option we can tell it to create the subdirectories but also any parent directories that don’t already exist. Allowing an entire directory tree to be created with one line:

Here we can see an entire directory tree “/new/directory/example/setfive” being created.

5. Extract specific pages from a PDF

$ pdfjam pdf1.pdf 2-4 -o 2.pdf

Using the pdfjam command we are able to take pages 2, 3 and 4 from the pdf pdf1.pdf and save them in a separate file, here called 2.pdf.

6. Create a thumbnail image for a PDF

$ convert -thumbnail x80 file.pdf[0] thumb.png

Here we are using convert to create a thumbnail for a pdf, with the [0] indicating that the thumbnail will be made using the first page of the PDF file.

7. Make all file names lowercase

(Assuming you have a bash like shell)

$ for i in *; do mv "$i" "${i,,}"; done

This command will loop through the directory and use the built in case modification extension that comes with Bash to change all the file names to be lowercase.

8. Create an animated gif

$ convert -delay 20 -loop 0 *.jpg myimage.gif

This can be accomplished using the imagemagick package, which can be installed with “sudo apt-get install imagemagick”. This allows for full image manipulation including conversion and editing.

9. Create a file with some text

$ echo "a new string" >> file

It appends the string into the file, followed by a newline, if the newline is wanted then by adding the -n flag after echo will append the string without the following newline.

10. Split up a file

$ split -b 50MB verylargemovie.mp4

Split will break up a large file automatically to whatever sizes you need. Here we’re breaking up our big movie file into 50MB chunks.

Bonus: Rerun the last command, replacing part of the command

This allows for an easy method to rerun a command with the swapped string which can be useful with long commands where finding and altering a single string by hand would be tedious.

Using the convert example from above:

$ convert -delay 20 -loop 0 *.jpg myimage.gif
$ ^myimage^newimage
convert -delay 20 -loop 0 *.png newimage.gif

Will re-run the command and create an image named “newimage.gif”

Posted In: General

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Unless you’ve been living under a rock for the last couple of years, it’s clear that smartphones are kind of a big deal. Today there are close to 2.6 billion subscriptions globally, and this number stands to grow rapidly as less developed markets turn into substantial electronic consumers.

With new applications and games hitting app stores daily, it’s no surprise that people are spending more and more time with their eyes glued to the glass screens of these compact, universal media agents. Phones have single handedly changed the way that people live, becoming pivotal for people to communicate, go online, and access and share information.

The ubiquitous nature of the smartphone has opened the floodgates of opportunity, creating new markets in the process and forcing pre-existing ones to modernize or be strangled at the hands of innovation. One market in particular that has been significantly impacted by the mobile revolution is the advertising and marketing industry.

The rise of the Internet era has led to a rapid decrease in the effectiveness of traditional forms of advertising media, and have forced the hand of the industry to take the plunge into to more digital forms. Marketing companies have to continuously find new and improved ways of reaching their targets in a world where TV and print simply will not do. One unique strategy that companies have used to connect with the masses and promote brand awareness is branded Apps. Smartphone users spend close to 90% of their time on devices using apps so they offer an incredible opportunity to connect with consumers.

Recently here at Setfive we have taken a look at building some brandable tools for mobile, and looked for the most original branded apps out there for some inspiration. Here are some of the most interesting apps that we found during our quest for inspiration.

Pop Secret Perfect Pop App

This app uses your phones speakers to listen to the pops coming from the bag of popcorn in your microwave, and tells you the precise moment when your bag of popcorn is a peak popped-ness.

Charmin SitOrSquat App

This app uses a map to display available public restrooms in your area and lets you know how clean they are (hence the name SitOrSquat). Additionally this app utilizes crowd sourcing, letting users to rate and write reviews about the public bathrooms that they use.

The Snow Report by North Face

So what has the North face been up to besides making incredibly epic TV commercials? That’s easy, they’ve been building a location based mobile app that helps users check the condition on powder before they head to the slopes. Check the status of runs around you or the 10 top slopes globally.

Tide Stain Brain

When stains happen, StainBrain gives you simple solutions on the spot. Blot or soak? Cold water or hot? Get the scoop on how to rid yourself of more than 85 different stains with on-the-go tips and easy, step-by-step washing instructions from the laundry pros at Tide.

Bosch Unit Converter: Professional converter for over 50 units

The Bosch Professional Unit Converter turns a smartphone into a universal unit converter. The ideal app for quick conversions on the building site or in the workshop. Completely free of charge and ads.

Posted In: General

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Picture the scene, it’s Friday night, you’ve got friends over and everyone wants to listen to some great music. The problem is everyone wants to jam to something different and you’re not thrilled to sit by your laptop all night. Enter, the TxtyJukebox.

TxtyJukebox lets you setup an event which creates you a unique number which users can text in song requests to. As TxtyJukebox receives song requests, it searches YouTube for music videos and then places the videos into your event’s queue. And then if you hook up TxtyJukebox to a TV you’ll be able to jam to videos on a big screen with big room sound. But wait, there’s more! If you have a Chromecast you can connect TxtyJukebox to your Chromecast via our app. The Chromecast app will launch from within http://jukebox.setfive.com/ so there’s nothing to download or setup.

So how does TxtyJukebox work under the hood? Well sit tight, technical details lay ahead. The webapp itself is a standard Symfony2 app along with the usual suspects – Bootstrap, Underscore, and a sprinkling of jQuery. Along with that, we’re using Twillio’s REST API to handle SMS along with a “webhook” from Twillio to the webapp to recieve messages. In addition, we’re leveraging the YouTube API to search and load videos which are then loaded into an iframe. Finally, the Chromecast app is HTML/CSS/JS powered by jQuery and underscore.

Building TxtyJukebox was a lot of fun and we’re thrilled that it’s been positively received. An awesome surprise was that Ryan over at Makeusof.com found it and incldued it in his post of How to Share Music from Multiple Devices to a Chromecast. As always, let us know if you have any questions or comments.

Posted In: Launch

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Labor day has come and gone so summer is officially over. We sat down with our intern Phil to chat about his time interning at Setfive.

Favorite Part About Interning At Setfive?

My favorite part about interning at Setfive was being introduced to so many different programming tools, and having the ability to increase my programming skill set. This summer I learned about PHP, the Symfony 2 Framework, MYSQL, I improved my JavaScript skills, learned some Angular.js, and even learned how to write unit tests. I was exposed to so many new things that everyday was fun and no two days were ever the same.

The environment here encouraged questions, and allowed me to ask and receive answers to anything I wanted to know more about. Some of the guys would even go out of their way to send me related documentation about something if they felt that they couldn’t confidently answer it themselves.

Working under the guys here was an incredible experience, I was given the freedom to make mistakes and figure out problems on my own, but at the same time was given sufficient structure to make consistent progress. It was awesome to have the comfort of knowing I had a smart, qualified person to guide me in the right direction if I ever got too stuck on any one problem.

Most important thing that you learned?

The most important skill that I learned was definitely an improved conceptual understanding of MVC, and that while sometimes using this pattern slows down your programming, in the long run it helps you create readable, modular code.

I also learned that installation is just the worst.

Most Memorable Moment?

The most memorable moment of the summer was the first time we used the Txty Jukebox in the office. It didn’t quite work the first time around, however, watching people use and get enjoyment out of something that I helped to create was something that I’ will never forget.

Where do you want to go from here?

From here I definitely want to continue building custom applications. I’ve spent the last part of the summer teaching myself objective-c, and the skills that I’ve learned here will definitely help me make the transition into developing iOS applications.

Top 5 Things To Eat

  1. Buffalo Soulja – Darwins (Only available on Thursdays)
  2. Mango Bubble Tea – Dosa Factory
  3. Steak Sammy – Orinoco
  4. Burger topped with shortrib meat – Charlies Beer Garden
  5. Chicken Pad Thai – Thelonious Monkfish
  6. Honorable Mention: Cuban Sammy – Plough and Stars

Posted In: General

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A couple of months ago I decided to use Scala with the Play Framework for a Bitcoin related project. The decision to use Play was motivated primarily by the goal of implementing a “pure” Bitcoin application, leveraging bitcoinj to interact with the Bitcoin network as opposed to a third party service. Overall, everything was pretty straightforward but one thing that stuck out was how the Play framework handles parsing JSON.

Coming from loosely typed PHP I knew that handling serializing and unserializing of JSON data was going to be different but Play’s approach is a completely new paradigm. If you use Play with Scala, you can handle parsing JSON input back into objects using Scala’s Parser Combinators syntax. I’m going to butcher this description so check the wikipedia entry but the idea is that parser combinators let you “build up” increasingly complex parsers by combining functions that recognize smaller inputs. If you’ve taken a compilers or programming language class, Scala’s parser combinators end up looking a lot like Backus–Naur Form for the input you want to recognize.

Anyway in an effort to learn Scala a bit better and take Parser Combinators for a spin I decided to build out a small project. What I ended up building is a really simple implementation of a Turtle Graphics system. You basically feed it a series of “turtle” commands and it’ll move the “turtle” around on a Swing window drawing some graphics.

Here’s an examples of the input and output:

Which was generated by:

Overall, parser combinators seem to be a really powerful Scala feature that would make developing domain specific languages relatively straightforward. Compared to messing around with a parser generator, using parser combinators seems to more closely mirror what the formal grammar of a language would be.

The entire project is available on GitHub. If you clone that project, there’s a runnable JAR which you can run with:

java -jar logoparser.jar /home/ashish/workspace_java/logo-parser/samples/face.txt

You’ll need to provide an absolute path for the “filewatcher” to work. Once the app starts, if you modify the file you specify it’ll repaint the canvas with your updates. Note: I’m not sure why but certain text editors don’t seem to register in the Java “filewatcher” interface so if your updates aren’t showing up try using a different editor.

Anyway, as always I’d love any feedback!

Posted In: Scala

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