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outrun
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Profound problems that drive us crazy

February 21st, 2018, 7:03 pm

I read this rant about Spotify 3 times now. I can see it's probably v important but it's missing a good diagram with queues and trees. Do you understand the core issue?

"
When you add a song to your queue using Add to Queue, rather than adding it to the main queue, it's added to a special sub-queue called "Next in Queue." Next in Queue behaves drastically different than the regular queue:

1) Next in Queue remains next in queue, even if you move to another location in the queue. So if you skip to the end of an album, use Add to Queue on an album, and then skip back to the beginning of the album you were listening to, it won't play the album in the queue and then the second album. It will play the first track of the first album, then the entirety of the second album, then the rest of the first album.


2) Once a track in Next in Queue is played, it vanishes from the playback order. If a song in Next in Queue ends and you hit previous track, it won't be the song that just played, but the last song from the regular queue that played. Tracks can't be replayed unless you restart them before the end of the song.

3) Tracks in Next in Queue do not shuffle when a queue is on Shuffle play. Tracks are played in the order they were added to Next in Queue, and then shuffle will resume in the regular queue.
"
 
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Traden4Alpha
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Re: Profound problems that drive us crazy

February 21st, 2018, 7:58 pm

OK, I never listen to music so I've got zero experience with these apps.

To summarize, it seems there's two queues: 1) the main queue holding some sequence of long-term possibly shuffled favorites and 2) the next-in-queue being used for short-term listening.

Overall, the software's behavior mostly makes sense to me under the assumption of the listener has both long-term and short-term listening desires. In the long-term, the main queue sets the sequence. But in the short-term, there is the special next-in-queue

The challenge for the queue manager is in handling "Add to Queue" in some "intuitive" manner. First, does the listener expect "Add to Queue" tracks to drop into the very end of the main queue (and play hours or days after the "add" command) or should they come up sooner? If they expect short-term play, then "Add to Queue" is sort of a LIFO queue prepended to the front of the main FIFO queue. And if the listener does two or more "Add to Queues", would they expect those songs to play in order of addition or reverse order? If it's a forward order, then "Add to Queue" needs to be a second not-shuffled FIFO queue in parallel to the main possibly-shuffled FIFO queue.

That Next in Queue tracks don't show up on the playback list is strange although maybe that is a way to ensure that newly added tracks (which may be just one-time test-listens) don't crap out the history file. (If I were a listener, I'd hate to have to constantly prune the main queue of songs I tried once and did not like) Perhaps if the listener likes the "Add to Queue" track while listening, then the "Add to Queue" item goes on some more permanent list.

Or maybe it's just a bunch of silly inexperienced programmers being told to implement random hacks to fix random complaints and there's no coherent system design. Maybe "Next in Queue" is some bolt-on functionality and trying to integrate it with the main queue and playback list would be too hard.
 
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katastrofa
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Re: Profound problems that drive us crazy

February 21st, 2018, 9:25 pm

The Queue is linked list and Next in Queue is FIFO?
I once saw an article about Spotify advertising its playlists. I decided to use one of those supposed to help you fall asleep. The music was so dull and repetitive that it made me jump out of the bed and go do some work...
Last edited by katastrofa on February 21st, 2018, 10:50 pm, edited 1 time in total.
 
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Cuchulainn
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Re: Profound problems that drive us crazy

February 21st, 2018, 9:29 pm

The music was so dull and repetitive that it made me jump out of the bed and go doing some work...

Morrissey, U2, ColdPlay?
 
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katastrofa
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Re: Profound problems that drive us crazy

February 21st, 2018, 9:33 pm

I like Morrissey. His new album is as good as the old stuff.
When I was a child, I listened to The Smiths and Depeche Mode. Everybody hated me for that, which made me an ever bigger fan of those.

It's just time to pay the price
For not listening to advice
And deciding in your youth
On the policy of truth


Image
 
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outrun
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Re: Profound problems that drive us crazy

March 3rd, 2018, 10:13 pm

The automated bonsai greenhouse heater turning on study results are in
Image
 
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Traden4Alpha
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Re: Profound problems that drive us crazy

March 4th, 2018, 1:03 pm

The automated bonsai greenhouse heater turning on study results are in
Image
I'd been waiting for this!

But does it mean what it seems to mean??? On a warm day, the heater never turns on (count of 0). On a cool day it turns on, warms up quickly, and turns off multiple times (high count). But on a very cold day, the heater turns on and never turns off (count of no more than 1). Heater count as a function of ambient temperature is a second order curve with two zeros.

Total on-time per day would be a better measure than frequency of on-events.

Note: a more detailed analysis of the pattern of on-off transitions could probably detect the cycling of the main heating system for the house. And an analysis of heater timing relative to the diurnal cycle could determine whether the bonsai is in a east, south, west, or north window. And an even more careful analysis could probably determine the geo-coordinates of the bonsai from the inferred fingerprint of sunny vs. cloudy days and a search of weather records in likely locations (e.g., a cold December means the bonsai is in the northern hemisphere and the diurnal cycle in UTC estimates the longitude to narrow the search space).
 
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bearish
Posts: 4510
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Re: Profound problems that drive us crazy

March 4th, 2018, 2:19 pm

Perhaps the tree itself should have a say in the matter? Something along the lines of this study (apologies to easily offended vegans): Learning by Association in Plants.
 
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Traden4Alpha
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Joined: September 20th, 2002, 8:30 pm

Re: Profound problems that drive us crazy

March 4th, 2018, 3:43 pm

Perhaps the tree itself should have a say in the matter? Something along the lines of this study (apologies to easily offended vegans): Learning by Association in Plants.
This is proof that vegans massacre and consume sentient beans!

(I feel most sorry for sprouts. They are the innocent infants of the plant world. All they want is a bit of clean soil, fresh rain, warm sun, and some room to grow. Instead, they are raised under atrocious crowding, ripped up by the thousands to be scattered on the leaves of dead adult plants, and only get to see the sun for a few minutes before going into the slavering cavernous maw of the voracious vegan.)
 
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Cuchulainn
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Re: Profound problems that drive us crazy

March 4th, 2018, 3:56 pm

And mushrooms: kept in the dark and fed sh*t.
 
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Traden4Alpha
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Joined: September 20th, 2002, 8:30 pm

Re: Profound problems that drive us crazy

March 4th, 2018, 4:43 pm

And mushrooms: kept in the dark and fed sh*t.
Not only that but one is eating the sex organs of the creature. How rude!
 
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outrun
Topic Author
Posts: 4573
Joined: April 29th, 2016, 1:40 pm

Re: Profound problems that drive us crazy

March 4th, 2018, 8:19 pm

The automated bonsai greenhouse heater turning on study results are in
Image
I'd been waiting for this!

But does it mean what it seems to mean???  On a warm day, the heater never turns on (count of 0).  On a cool day it turns on, warms up quickly, and turns off multiple times (high count).  But on a very cold day, the heater turns on and never turns off (count of no more than 1).  Heater count as a function of ambient temperature is a second order curve with two zeros.

Total on-time per day would be a better measure than frequency of on-events.

Note: a more detailed analysis of the pattern of on-off transitions could probably detect the cycling of the main heating system for the house.  And an analysis of heater timing relative to the diurnal cycle could determine whether the bonsai is in a east, south, west, or north window.  And an even more careful analysis could probably determine the geo-coordinates of the bonsai from the inferred fingerprint of sunny vs. cloudy days and a search of weather records in likely locations (e.g., a cold December means the bonsai is in the northern hemisphere and the diurnal cycle in UTC estimates the longitude to narrow the search space).
Very good analysis. I agree we need to try and contact this guy about the information erasure of counting number of heating moments rather than ISO  joules or heating time. Another reason to log heating time statistics rather than number of daily heating event is that he/she would be better able to hedge the energy consumption for his Bonsai heating system with heating degree day weather futures at the CME.
 
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Cuchulainn
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Re: Profound problems that drive us crazy

January 23rd, 2019, 9:56 am

Before the Big Bang there was NOTHING.

But what is NOTHING? I suppose only physicists understand this.

Is it bordering on Alchemy?
 
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FaridMoussaoui
Posts: 364
Joined: June 20th, 2008, 10:05 am

Re: Profound problems that drive us crazy

January 23rd, 2019, 10:30 am

As you like boundary conditions, and using space-time, here an answer from Hawking.
 
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Cuchulainn
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Re: Profound problems that drive us crazy

January 23rd, 2019, 10:51 am

That's gobbelly gook!

So, the universe is a Cauchy problem? 

The NBC (No Boundary Condition) means you only need to know when t = 0. 

But when t < 0? 
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