Why Care Block:
Yo yo, what’s up my Stata-ites! DJ Control+D is in the house because today we’re talking about making music with Stata. There’s a big trend in today’s age involving visualizations, but truth be told, visualizations are so last season. You’ve always been able to see your data, yet have you ever wanted to hear your data? “That’s absurd, I don’t need that.”
Yeah, you’re probably right... but today, this post is for the slacker: from the undergraduate struggling through their Stata homework, to the professional who’s bored with the day-to-day grind, our new command composer is there to brighten up your day and aid with your ever evolving procrastination techniques.
What is composer? It’s a way to create music. How is that music generated? You write a string of notes that get converted to the midi file format. Why did we do this? I’m still asking myself that same question while introspectively reevaluating my life. Truth be told, I love music. Not in the traditional sense, but in the very traditional sense – classical music and music theory has always been a passion of mine and this has been a passion project for a long time now.
Composer makes music in two separate ways. You can write songs from the command line and from a dataset. The command line approach is faster and is especially meant for ad hoc procrastination. The dataset approach is a more methodical way of creating music and actually allows for multiple tracks and multiple instruments.
Take our command line approach:
composer "D, 384D, A, A, B, B, *2A, G, G, F#, F#, E, E, *.25r, *.25Db, 768D" using tt.mid, play replace
We could have also written this first part as D, D, A, A, B, B, 768A, but it’s good to see the variations of this command. First we have notes: A, B, C, D, E, F, and G. Each note can be modified using a # (sharp) or a b (flat) which directly follows the note.
A number before the note shows the duration of the note. The quarter note takes the value 384 (3*2^7). This way it can be halved up to seven times with 384 representing a quarter note, 192 representing an eight note, 96 a sixteenth note, and so on. Rather than specify a value, you may also multiply the note by a number to modify the value of the quarter note.
Any number following your note denotes which octave or pitch your note will take. You may also change the instrument using a number or a named instrument available in the composer help file. For instance, say we wrote:
local n1 = "F#,A,E6,D6,E6,D6,A,D6" local n2 = "E,A,E6,D6,E6,D6,A,D6" local n3 = "F#,B,E6,D6,E6,D6,B,D6" local n4 = "G,A,E6,D6,E6,D6,A,D6" composer "`n1',`n1',`n2',`n2',`n3',`n3',`n4',`n4'" using ls.mid, play replace instrument("Pizzicato") bpm(240)
See if you can identify the song!
Now take our data set approach. It’s just like the command line approach, except the command now takes sets of three variables: time duration, note, and octave. Notes can be played simultaneously by adding another track (three more variables). This way we can build chords and add volume to our masterpieces just like Beethoven. But unlike Beethoven, we’re not creating classical masterpieces, we’re recreating pop music. If you weren’t able to pinpoint the song before, here’s the dataset aided version of our previous track.
use http://www.wmatsuoka.com/uploads/2/1/4/6/21469478/ls.dta, clear composer pizzdur pizznote pizzoct p1dur p1note p1oct p2dur p2note p2oct voicedur voicenote voiceoct using ls.mid, play replace bpm(120) instrument(Pizzicato Pizzicato Pizzicato Voice)
And there we have it, a fairly easy way to write music in Stata. Is this interesting? I hope so, especially if you’ve made it this far. I’m sure you’re wondering how useful this is though. Truth be told, this is probably one of the only things on this blog that I haven’t found a general use for but perhaps you can find some sort of practical application and share your thoughts. There will be one more post about music soon which deals with the actual analysis of music which will use composer. Until then, good luck and stay creative future Stata maestros!
Will Matsuoka is the creator of W=M/Stata - he likes creativity and simplicity, taking pictures of food, competition, and anything that can be analyzed.