Velocity is an important tool in Agile. Let me explain a little about what it is and why we find it useful.
Speed equals distance over time
One of the challenges when planning each two weeks’ sprint is working out how much work we can realistically commit to. That’s where estimates and velocity work together.
Since we estimate each task (using ideal hours), at the end of each sprint we can count up the values of all the tasks that we completed (only those that landed safely in the DONE column in Trello—that is tasks that have been both completed and successfully tested) to reveal our velocity for that sprint: how much value we were able to deliver to the project (or projects) during that two weeks’ timebox.
In theory that should then tell us how much we ought to expect to complete during the next sprint.
When I returned home from St Andrews this evening the whole of Anstruther was in darkness. There was a town-wide power cut. It turns out the power cut extended right down the Fife coast, as far as Leven, someone reported.
It was really quite eerie. Most houses were in complete darkness, a few had the flickering glow from candles at the windows. A couple of people were walking down the street using torches (‘flashlights’ for American readers).
The sky was spectacular: a blanket of pin holes. I had never seen so many stars while standing outside my house.
I walked into the house and found everyone walking around with torches. There were a couple of candles lit on the dinner table.
“We can’t find your bike light!” a tiny voice exclaimed in the darkness.
“It’s under my bed,” I replied. “I charged it over night.”
I handed Reuben and Isaac my keys and they went racing up the stairs to find it. The small LED torch on my keyring lighting the way. (I always carry a torch with me!)
I walked upstairs, ducked under my desk for a moment and then asked Isaac to switch on my desk lamp.
Suddenly the room was bathed in light from a 7.5 watt 3000K LED bulb.
“How did you do that?!” Isaac quizzed.
“Aha!” I said, “I have an uninterruptable power supply. It’s like a giant battery.”
We saw out the rest of the power cut sitting in my study: the only room in the house with any electric light.
I opened my curtains to show off to the neighbours that we had electricity.
Uninterruptible power supply
Uninterruptible power supply
A few years ago we experienced quite a few power cuts here in the East Neuk. I got fed up of my PC suddenly dying when the power went out, even just with short blips in power. So I bought myself a UPS, an unterruptible power supply.
As I said, it’s like a giant battery into which you plug your equipment. It monitors your power supply and if the voltage suddenly drops out then the UPS immediately kicks you over to battery power. It announces it with a satisfying ‘click’, and sometimes even a ‘beep’.
The UPS I have — the APC Back-UPS ES-700VA — which cost me about £80 a few years ago, doesn’t have a massive amount of power but it does give me a few minutes to save my work and shut down my PC safely.
But this evening it occurred to me that I could simply plug in my 7.5W desk lamp into it and get maybe over two hours out of it.
I certainly recommend getting a UPS or two, not just to safeguard your data but look how handy it is in a power cut.
I wake up most mornings to Planet Rock radio on my beloved Pure Evoke-1XT Marshall DAB radio. But that’s in my bedroom, I don’t currently have a DAB radio in my study and Screamer Radio no longer works for Planet Rock.
Which got me thinking: could I somehow convince my digital music player of choice, MusicBee, to stream Planet Rock? It seems to handle pretty much everything else I throw at it.
The answer is yes; this is how in three easy steps.
1. Find the Stream URL
The first thing to find is the URL to stream Planet Rock. This one currently works for me:
Next, we need to tell MusicBee to use that stream.
File > Open Stream
That’s as simple as opening the menu and selecting:
File > Open Stream.
Then paste in the URL and click OK.
Paste the URL then click OK
This may take a few seconds while MusicBee connects to the streaming audio feed and then BINGO! you’ll suddenly be listening to Planet Rock on your PC.
Don’t go setting your watch, though, to the streamed version. It can have a few seconds delay between broadcast and it emerging from your PC’s speakers. (My PC stream is currently 1 minute 25 seconds behind my DAB radio broadcast.) This is due to the software buffering enough data to ensure continuous playback, so that if some data goes missing and has to be re-requested from the server or if there is a local data bottleneck the audio doesn’t suddenly drop out.
What’s nice is if you use the first URL (the one ending /planetrock.m3u) then MusicBee will also display the name of the track currently playing:
Now playing…
3. Save the stream as a playlist
The final thing we need to do is tell MusicBee to remember this station. It would be a bit of a hassle to have to find, copy and paste that URL every time you want to listen to the radio.
Again, that’s simple.
Right-click the name of the track
From the context-menu select: Add to Playlist > <New Playlist>.
A new playlist will be created in the Playlists panel, with the edit caret waiting for you to give it a name.
Enter a meaningful name, mine says Planet Rock DAB.
Then press Enter to save it.
Conclusion
That’s all there is to it.
While I usually listen to MusicBee using the compact player view, when listening to streamed radio I prefer the mini player view which also pulls in the current track’s artwork.
Screenshot of code from The Guardian website with WE ARE HIRING written in ASCII art
This evening I was reading an article by Giles Fraser on The Guardian website and I was intrigued to understand how they coded the drop-cap at the top of the article:
.drop-cap > .drop-cap__inner
So being versed in the ways of the web developer I highlighted the letter, right-clicked and selected Inspect (I’m using Google Chrome, other browsers are also available). This opens a code inspector where you can poke around the HTML, CSS and JavaScript that builds a webpage, and it even allows you to edit it in situ to better understand how it all fits together.
I smiled when I saw, at the top of the HTML code, written in a comment in a combination of text and ASCII art: