The Whiteboard

Jimmy Hoffa

12:03 AM

@MichaelT Race for the Galaxy?

psr

boardgamegeek.com/boardgame/28143/race-galaxy

Ampt

looks fun

user55340

12:24 AM

@JimmyHoffa (and @Ampt) - a very good AI implementation: keldon.net/rftg

user55340

12:51 AM

@Telastyn the real problem is when you have crazy billionaires going after trophy animals. I'm sure that one was one of a kind... well, maybe.

Telastyn

?

user55340

Steven Spielberg (of Jurassic Park) next to a trophy triceratops?

Telastyn

what is that in reference to me saying?

jane

@MichaelT as I was asking... about that uibezierpath, is it possible to put some gesture responder once it's drawn in the screen?

user55340

I think it was about the Facebook rant the other day... though I might have misread it (small mobile screen and what not)

jane

12:53 AM

@MichaelT and thanks for the note :)

Telastyn

oh, whatsname was talking more about it

user55340

(and I can't edit it now... sorry... @whatsisname pretend that was for you instead)

user55340

@jane I want to say yes, though I haven't done that level / depth of Cocoa coding in a long time. If it isn't possible to get that UI Object bound, it might be possible to test if something is within it via containsPoint.

user55340

Another approach would be to use it as a clipping path on something else (via addClip) and have that something else have the responder.

Nick Alexeev

I saw a website, which cataloged software design patterns. The curious thing was that it also showed how frequently each pattern was used. The scale had 3 gradations: rare, moderate, frequeny. Of course, this indicator was rough and relative.

I can't seem to find this site again, unfortunately. p.s. Found it

jane

1:01 AM

@MichaelT, clipping path is interesting, I would try that. thanks for the advice!

user55340

And old objective C project of mine: github.com/shagie/MacSums

user55340

(note that it was written back in 2010 - so its a bit older than that first commit)

user55340

Its meant to help solve Killer Sudoku puzzles. "I've got a region of four cells that sums to 22, - it must have a 4 and can't have a 5 - what are the possible combinations?"

user55340

I got stuck with porting it to iOS at the time. The button bar that I use on Mac can have multiple selects - the iOS one couldn't. So I was going to have to implement a custom control and then moved on to other projects.

whatsisname

1:22 AM

yes, I was originator of the facebook rant yesterday

user55340

1:43 AM

And I wish I got refunds on close votes or deleted posts. programmers.stackexchange.com/questions/291246/… -- that just wasted one.

user55340

user55340

Ahh! That's why. His IP address is in the original history.

user55340

2:10 AM

You need to identify exactly what your question is. Is it implementation, getting around firewalls (or what to do when you find yourself on one), attempting to mask your identify, asking about what to do with the C&D that you got, or the fine print in the TOS when your ISP drops you, or something else. You really need to describe your question and stop being so coy about it. — MichaelT 1 min ago

user55340

OK - let me delete this one and re-ask. Thanks! Very much appreciated. — Steve 34 secs ago

user55340

That will be a third question, which at this point I will guess will likely be closed too... which will make for the three recent questions being down voted, closed, and/or deleted... question bans start somewhere around there IIRC.

user55340

I really wish I had refunds on close votes on deleted questions.

user55340

That's four close votes that have disappeared to the pink background already... 2.5h in from vote reset.

user55340

2:21 AM

user55340

And another from an hour ago.

user55340

33

Q: Refund close votes for questions deleted on the same day

When a question is deleted the same vote-day as it was closed, refund the close votes cast on the question. There are three situations where this comes up: Question has a close vote or two, a comment tells the OP that this is off topic (or about issues with the question) and the OP self delete...

enderland

Hazmat Highway to Hell with High Pressure Gas Cylinders (No Music)

►

user55340

Flying Semi Truck Crash Caught On Camera In Indiana

►

enderland

@MichaelT that guys reaction is kind of funny

Robert Harvey

2:54 AM

@MichaelT [Watches truck crash videos for next half hour... Can't look away]

user55340

@RobertHarvey Don't you want to live in Russia now?

Robert Harvey

In Soviet Russia, truck crashes you.

user55340

The most dangerous traffic light in th world ( Rus

►

Robert Harvey

@MichaelT LOL youtu.be/RRGG2g00Rzo?t=6m8s

user55340

@RobertHarvey the 'yep, thats two wheeling' woman?

user55340

2:59 AM

btw, if you want an entire site of... fun: /r/catastrophicfailure

user55340

355-foot 700 Ton Ship Flips

►

user55340

(background)

user55340

(and video - at 2:20 is quite interesting for a view of the galley)

user55340

3:20 AM

Did you know that Budweiser makes a line of mineral water? Its called Bud Light.

user55340

Thats four votes to the pink background tonight.

user55340

overexchange

3:37 AM

for sequential data model, we have linear/binary search algo to search data.

are there any other search algo for sequential data models? array/linkedlist

Duga

4:12 AM

Your question is off-topic here. Perhaps Programmers or Software Recommendations — Ajoy 40 secs ago

user114359

I know this is a duplicate of something but I cannot find it. Maybe @gnat can find it?

user114359

-1

Q: Advantage of generic base class

What's the advantage of having a generic base class and a derived class having itself as the generic parameter on the base class. e.g. public abstract class MyBase<T> {} public MyDerived : MyBase<MyDerived> {}

c# generics

jane

12:06 PM

Good evening! :)

Thomas Owens

Happy Coffee Day!

jane

Oh yea, happy Coffee Day! :)

Jimmy Hoffa

12:30 PM

Happy coffee day

Thomas Owens

The cafeteria once again has "(non-alcoholic) coffee liqueur flavored coffee".

Jimmy Hoffa

@whatsisname I don't understand why people are ranting about this... did they just now realize that there's a bunch of rich assholes going around shooting wild animals just because they can? It's an industry, it didn't just pop up because this one jerkface. Last time I checked tagging an animal didn't make it any more important than the other countless ones people hunt

@ThomasOwens how was the coffee flavored coffee yesterday? And it's coffe liqueur flavored? That's curious

Thomas Owens

@JimmyHoffa I didn't get any yesterday. They were brewing it when I went down for my last cup and I didn't want to wait.

Jimmy Hoffa

BTW, I know this is old, but always worth another larf thedailywtf.com/articles/The_Brillant_Paula_Bean

Atwood is from (or went to school in?) Boulder? Who knew

enderland

1:11 PM

@JimmyHoffa one of the bloggers I follow lives out there (well close)

@MichaelT that's where I got that video from in the first place ;) though that ship is intentionally doing that, I think I've seen taht video before

Ampt

1:33 PM

Happy Coffee Day!

@MichaelT that's hardly fair, it was clearly meant to do that :P

Jimmy Hoffa

yeah, I need to get better about that... I keep delaying making my pot in favor of getting shit done right when I get in

Ampt

Remember, a coffee day is a productive day!

user55340

@Ampt now put on an engineer hat and design the toilet in there.

Ampt

Contemplates taking out ads for coffee day quotes...

@MichaelT Makes sign for bathroom saying only available during horizontal alignment

user55340

Or the galley with the coffee pots.

Jimmy Hoffa

1:38 PM

@Ampt We have HiLine coffee ship us our coffee at home - every package has a business card in it with a different coffee quote - right here I have on my desk "MAY YOUR COFFEE BE STRONG AND YOUR WORKDAY BE SHORT."

Ampt

shit.... that is a problem

user55340

(Hint, it's at 2:20 in the second video)

user55340

FLIP marine research vessel

►

user55340

Actually you can see it there.

Ampt

Can you imagine designing the load members on that long rod supporting the top half of the ship?

Jimmy Hoffa

1:40 PM

...if an entire room; walls, floors, cieling, swivel on a gyroscope like one big box, and the one next to it the same....how could you get from one to the next?

user55340

Hmm. Ask a real engineer. Hey, @GlenH7 what do you think?

user55340

@JimmyHoffa the doors are on the walls and floors

Ampt

they likely have two sets of halls and stairways - one for each orientation

user55340

Rotate, ceiling becomes wall, wall becomes floor.

Ampt

the rooms themselves don't rotate, only things in the rooms

Jimmy Hoffa

1:42 PM

@MichaelT you mean in that vessel? That vessel doesn't operate like I mentioned - the floors and walls and cielings move

Ampt

rotating rooms adds a whole new level of hell haha

Jimmy Hoffa

@Ampt I am asking about an alternative solution - how would you solve for the spaces between? Oh hell maybe the real solution would be to only have one big cube with all the rooms on one big gyroscope...

Ampt

@JimmyHoffa rooms have to be cylinders if you want to flip the whole room, otherwise the corners would bash together

huge waste of space designing for whole rooms to rotate

Jimmy Hoffa

@Ampt unless there was sufficient gap

Ampt

packing efficiency becomes packing inefficiency very quickly

Jimmy Hoffa

1:44 PM

If you had the engine - or a secondary engine - also driving the gyroscope, you could make it sufficiently large and functional to maintain a very large set of rooms in one segmented box - or orb - even at all times. Would that however be seaworthy though?

Ampt

the optimal way to do it would be to have each room rotate individually so that you only need tan(45)n from the center of your room to the outside wall of the next

the video states that the ship has no propulsion - it's probably a very hard problem to solve, turning an engine on it's side like that

especially one large enough to power a ship

user55340

@Ampt btw, generators tend to only work in one orientation... Right?

Ampt

all your oil ends up feeding one cylinder

@MichaelT eh... smaller ones not so much, especially if you just fuel inject them

not enough pressure difference from the top to the bottom I would think

Jimmy Hoffa

@Ampt interesting...

user55340

300 kW iirc.

Ampt

1:47 PM

remember, pressure is not linear with depth

300kW is... 400hp

easily doable with a small block v8

and that you could mount on a trunion, if you even needed to

again, not sure if the pressure differential on that scale would hurt too much

or you could just design for it - maybe use an old allison v12 from WWII

those are made for essentially any angle

Jimmy Hoffa

could that drive a small-building-sized gyroscope?

....from inside the gyroscope?

Ampt

> The V-1710 has 12 cylinders with a bore and stroke of 5.5 by 6 inches (140 by 150 mm) in 60° V-format, for 1,710.6 cu in (28.032 L) total displacement

> The initial rating of 1,000 hp (750 kW) was incrementally increased; the final V-1710-143/145(G6R/L) was rated for 2,300 hp (1,700 kW)

one of my favorite WWII era engines

I'm gonna go out on a limb and say yeah, it could

Jimmy Hoffa

Then the only question I guess is... would such a structure as a small building sized gyroscope with a small building held level inside...be seaworthy?

Ampt

you would just need to give it some external attachment at the center of rotation and a ton of gearing

enderland

@Ampt sub diesels were the best

Jimmy Hoffa

1:52 PM

@Ampt I'm imagining a 4 story building, where the first story is entirely the gas tank for that thing to do it's business

Ampt

it may be more comfy since it's all gyroscopically stable

@JimmyHoffa you're not far off with a compression of only 6.5:1

Jimmy Hoffa

@Ampt comfy yes, but how well would the whole structure stand up to the stresses of the sea?

Ampt

@enderland until you turned them on while you were below the surface. Whoops! There goes all your breathable air in 2 seconds or less!

enderland

@Ampt they had snorkels by the end of the war

but you still had to be pretty close to the surface

Ampt

@JimmyHoffa after seeing that they managed to lift the business end of that entire thing up out of the water on that little pillar, I'm guessing they could design around the stresses, yes

your ship would be noticably larger though

@enderland can you imagine hydrolocking one of those engines?

Jimmy Hoffa

1:55 PM

@Ampt screw space engineers, ship engineers needs to be a thing now

Ampt

you'd shoot a rod straight out your hull

@JimmyHoffa I hear they're adding planets soon. throw in some water and flotation mechanics and we're pretty much there!

enderland

submariners in WWII era were crazy

Jimmy Hoffa

@enderland pshaw, submarines in the civil war FTW.

enderland

casualty rates were crazy high for submariners in WWII (though I guess the rate was high in Civil War, too. ha)

durron597

@ThomasOwens @MichaelT intro-to-programming

Jimmy Hoffa

1:59 PM

@enderland considering how long the story existed merely as a myth, I'm going with it was 100%

durron597

Also good morning progs! Happy coffee day

Ampt

crazy mofos trying to stick bombs on the bottoms of ships.... seriously they were nuts

durron597

@JimmyHoffa This person came into an SO chatroom to ask for help, is there a solution to your knowledge?

Ampt

@MichaelT did you hear? the new intellij 15 preview has native hidpi support now. Trying it now

step 1: format your hard drive to remove any trace of haskell.
step 2: download java

Jimmy Hoffa

@durron597 there likely is but I don't know one - though he's basically asking to do something that has been well and truly obsoleted industry wide - WebSockets replace what he's asking to do, and there's definitely WebSocket support in the modern haskell web frameworks

Ampt

2:04 PM

@MichaelT it's glorious! it only took them 9 months and all

Jimmy Hoffa

holding the HTTP connection alive was the mega-alpha version of WebSockets when people were first trying to use HTTP for server side push behaviours... He should just use WebSockets

durron597

@JimmyHoffa Can you put that into a comment? They've already left the SO room I think.

Thanks

Jimmy Hoffa

Just use WebSockets - you don't want to do classic long-lived HTTP connection for server side pushes, WebSockets were standardized to replace this kludge. Googling Haskell WebSockets brings up this immediately, though I'm willing to bet the major web frameworks all have their own WebSocket support — Jimmy Hoffa 19 secs ago

durron597

@JimmyHoffa Tyvm!

Jimmy Hoffa

Anti-rolling gyro

Ship stabilising gyroscopes are a technology developed in the 19th century and early 20th century and used to stabilise roll motions in ocean-going ships. It lost favour in this application to hydrodynamic roll stabiliser fins because of reduced cost and weight. However, more recently (since the 1990s) a growing interest in the device has reemerged for low speed roll stabilisation of vessels. The gyroscope does not rely on the forward speed of the ship to generate a roll stabilising moment and therefore has shown to be attractive to motor yacht owners for use whilst at an anchorage. One of the...

but that's a completely different device than I refer to - that is simply a gyroscope in the vessel acting as an active counter balance

durron597

2:18 PM

@MichaelT @GlenH7 I don't want to edit this up to the front page. Can has delete votes pls

user55340

@durron597 mine is already there. It's old close - any 10k can cast away on it.

durron597

@MichaelT Yeah but I don't even have 4k

I forgot that I can't see delete votes, I've been spending a lot of time on SO recently.

Robert Harvey

So that "passing an exception through an out parameter" question. Which would be preferable, returning an exception via an out parameter, or converting it to some sort of error code?

For some reason, the idea of returning an exception makes me uncomfortable. Is there something evil that the caller could do with an exception? Isn't a stack trace too much information to be leaking?

And swallowing an exception doesn't seem like a good thing either.

Jimmy Hoffa

pfleh. This is why I prefer the Exception monad to this try catch garbage

Robert Harvey

Does the Exception monad propagate through the call stack like an exception does, or do you capture it in an object and return it?

Jimmy Hoffa

2:28 PM

monads act as a barrier - nothing comes out without you deciding how to handle the barrier - in the exception monad that decision is "Was there an error or not? If so X, otherwise Y"

Robert Harvey

It sounds like what she needs is an Exception monad in C#.

Or simply an object that returns error information.

Jimmy Hoffa

...in C#, just throw the exception...

The exception monad gives the same behaviour as a throw but without losing extensibility

Robert Harvey

Yeah, she's eliminated that possibility, and logging.

durron597

@RobertHarvey I answered it too just now, fwiw.

Robert Harvey

@durron597 If you used an anonymous type or a tuple, you could eliminate the need to add another class.

Ah, never mind. Yeah, a new class is probably the right way to go. If you're going to do that, though, you might as well throw those two things in a class with the collection, and just return everything together.

durron597

2:36 PM

@RobertHarvey Perhaps

Robert Harvey

That way you can avoid declaring an out parameter.

Which was my objection in the first place.

durron597

@RobertHarvey I would probably create two classes and compose the exception class into it, because I don't want exception behavior in the same class as useful behavior

Robert Harvey

Well, you're going to get crap back anyway, if the exception is thrown.

Thomas Owens

@durron597 I have no idea what you're going on about now.

durron597

@ThomasOwens STCI. It's basically a tag like learning

@RobertHarvey I edited with this conversation in mind.

Thomas Owens

2:42 PM

@durron597 There's nothing to do there, though.

durron597

@ThomasOwens Ah. Right.

Thomas Owens

:P

Duga

3:00 PM

Your question might be a better fit on Programmers. This is an architecture question, not a programming question. — theMayer 57 secs ago

Jimmy Hoffa

3:26 PM

@durron597 I presume your answer about that thing involved creating a class with a T and an Exception -> You're halfway to the exception monad right there. All you need to do now is add a function:

public WhateverClass<U> Next<U>(Func<T, WhateverClass<U>> thingToDo) { return this.Exception != null ? new WhateverClass<U>(default(U)) : thingToDo(this.Value); }

Ampt

@JimmyHoffa sorry, you had me up til monad.

2

durron597

@JimmyHoffa Do you try to make code unreadable on purpose?

enderland

@durron597 no he just writes haskell ;)

Ampt

Poor Jimmy, just trying to help us write better code, and we just shit on his love for functional programming.

2

Jimmy Hoffa

4:04 PM

@Ampt you can't shit on my love for functional programming, it's immutable; you can only shit on copies of it.

9

psr

Is it worth writing tests for my Mercury HTML generating code? It's a bunch of stuff like return h('div',{classname:item.IsHidden ? 'hidden' :''},[h('div',[item.text])]); It seems like they would be fragile enough that they would be more trouble than it's worth.

Ampt

4:19 PM

@JimmyHoffa rather I would create a new copy in which I construct it with the shit on top of it, no?

durron597

So my third party API returns a class that looks like this:

Ampt

@psr you should use regex!

durron597

public class ThirdOuterStructure {
  List<ThirdObject> firstList;
  List<ThirdObject> secondList;
}

I want to wrap this class, and I want to provide all the information available, but I don't want clients to depend on ThirdObject

ThirdObject is just a POJO

Ampt

convert it and then wrap your converted class?

not sure how performant it has to be, that may not be the best option

durron597

@Ampt That's exactly what I'm worried about

Ampt

4:27 PM

can you convert it as it's received?

Jimmy Hoffa

@durron597 what is the purpose of this structure? Are you writing zippers in Java?? O_o no, certainly not. You must be drunk

durron597

I'm thinking about lazy loading

Ampt

or is there a third party library doing the receiving/packaging

durron597

@JimmyHoffa It's an order book

Jimmy Hoffa

@durron597 why does it have a first and second list?

oh they aren't a list sequence

they're different types of lists

Ampt

4:28 PM

I'm just thinking that maybe you can recoup the cost of putting it in the POJO in the first place and use that time to put it into an object you want

durron597

@JimmyHoffa It's the bid and ask of a particular product.

I could totally rebuild the list structure with my wrapper object

I mean, maybe it's fast enough

Jimmy Hoffa

right. So why don't you just create a decorator if that's what you want? Would that cause people to rely on the POJO?

durron597

I'd like to be able to just wrap the whole thing without actually changing the underlying data structure

I think I'm going to have to reimplement List.

Ampt

are you giving them access to the underlying objects?

or are you providing methods to do that for them

Jimmy Hoffa

public class WhatPeopleShouldRelyOn { private ThirdOuterStructure _bla; /* information you want to provide */ } ??

what's wrong with the above?

Ampt

4:30 PM

I believe the second means that there aren't any dependencies on ThirdObject

durron597

I need to provide getBids().iterator() for instance

@Ampt Yes, that is the biggest thing. I don't want any dependencies on ThirdObject

Ampt

yeah, you'll just make a decorator list then

durron597

ThirdObject is actually IPriceLevel, which has a method getPrice() which returns third.party.library.ScaledDecimal which I also don't want to depend on.

If we agree the right thing to do is reimplement List with their List as a backing object then I can do the rest myself, I'm just not sure that's the right thing to do.

Ampt

hey, I'm just a sock, I accept no responsibilities on the correct answer.

but there you just add the overhead of the extra layer of abstraction, which is negligible. so if performance is your problem, that should solve it.

durron597

@Ampt What if you're a 1970's labor union leader?

Ampt

4:34 PM

@durron597 I suspect the answer is the same

Jimmy Hoffa

@durron597 The right thing to do is have their List as a backing object. What's not clear however is what interfaces your object should provide; you suggest List, this is likely the right interface to provide to consumers - but the real question is what interface is going to be best for consumers ? Think about POLA and all the other important points to note regarding deciding on the design of the interface you'll provide to consumers. List may be the correct one to provide; I don't know.

durron597

@JimmyHoffa Yeah...

I think list is correct but I will think about it more.

Jimmy Hoffa

@durron597 thinking is good; trying is also good. Put it together real quick- try to consume it, see what you think of it then. Extensions to the interface you find missing for the consumers? Pitfalls you see the consumers will fall into? Find it feels perfect? Etc.

durron597

@JimmyHoffa Well I'm currently sending an unwrapped object to different parts of my system.

This is the last dependency on their objects that gets outside of the wrapper package

Jimmy Hoffa

This is where practice-practice-practice comes in key to doing this shit right, the practice makes you faster at whipping up design attempts - so you can try these things quickly and see how they'll actually play

I'm constantly writing up entire design prototypes and attempting to change designs - two, three, five times before I settle on which approach seems right.

durron597

4:45 PM

The problem with reimplementing List is that it has so many methods

It's hard to whip one up quickly, that's why I let the unwrapped version make it to production

I'd have to reimplement Iterator too

Ampt

5:20 PM

can't you just basically pass the methods on to the sublist?

durron597

@Ampt ThirdDifferentObject = ThirdObject.getData() and I don't want a dependency on that, either.

Ampt

public Iterator<Object> getIterator() {
    return firstList.getIterator();
}

durron597

public Iterator<ThirdObject> getIterator() {
    return firstList.getIterator();
}

@Ampt See?

Ampt

BAM! problem solved

kicks feet up on desk

I think we're done here, folks

psr

@durron597 What about Cast<IEnumerable<ThirdObject>,IEnumerable<ObjectILike>>

Ampt

5:30 PM

implicit casting = best casting

Jimmy Hoffa

@psr because Java would ever have useful generic facilities

psr

@JimmyHoffa You had me at "because Java"

durron597

@psr I don't know how to do that in Java, but I'm not sure it's impossible... maybe it is?

psr

@durron597 Cast to scala? I have no idea.

durron597

Well, wait, it's not Cast so much as Transform

Ampt

5:32 PM

Cast<IEnumerable<Java>,IEnumerable<Scala>>

psr

@Ampt Should work.

Ampt

Ship it!

durron597

lazy evaluation would be so good here. maybe i'll rewrite the whole codebase in haskell

Ampt

you know, if you do your transformation from java to scala in python, you can just duck type it!

Thomas Owens

Hmm. I have a problem that I'm sure should have been solved hundreds of times before. I have a directory structure that contains a whole bunch of files. Ultimately, these files can be grouped into two different types, each of which represent a certain collection of files.

Ampt

5:34 PM

recursion

use recursion. It'll work, trust me

Jimmy Hoffa

@durron597 ironically - you work on software that is been really the main stay of what Haskell has been used for in industry - trading desk software.

Thomas Owens

@Ampt Uhm. That's a good way to navigate the directory structure. But I was thinking more about creating the objects.

Ampt

@ThomasOwens no, no. You need to use recursion inside the folder too. Maybe sprinkle a little regex on there to make it really fly.

Thomas Owens

@Ampt That's...not helpful. :\

durron597

@Ampt and some HTML parsing

@ThomasOwens He's a sock, what do you expect?

Jimmy Hoffa

5:35 PM

Most all of the real functional programming language use in the industry is in financial instrument software because quants are all mega mathy and so it's natural to them to write their algorithms as such

Ampt

@ThomasOwens it's lunchtime on thursday, I ran out of helpfulness early this week.

1 hour ago, by Ampt

hey, I'm just a sock, I accept no responsibilities on the correct answer.

durron597

@Ampt brb, celebrating coffee day

Robert Harvey

A Cautionary Tale of Learning to Code

Why Learning To Code is So Damn Hard

Ampt

@ThomasOwens you want to seperate them?

Jimmy Hoffa

@ThomasOwens you have a set with a partition. Define the partition conditional...

psr

5:37 PM

@Ampt Regex worked great for my unit testing! I wrote a regex that matches everything and ran it against the source code. 100% coverage in just a few seconds of test writing.

durron597

> Choose one language to learn: JavaScript, Ruby, or Python.

or Java or C# or Haskell or PHP or ...

Thomas Owens

@Ampt No, I just want to make objects that point to the files and have a little bit of metadata.

Ampt

durron597 quickly runs out of breath and dies

Thomas Owens

@JimmyHoffa I don't know what you mean by that.

Ampt

@ThomasOwens I'm not seeing the problem yet

Thomas Owens

5:38 PM

These two objects are parent-child, too.

Jimmy Hoffa

@ThomasOwens you have a set (of files?) that should be partitioned into N sets (of files?)

Thomas Owens

No, no.

Jimmy Hoffa

you didn't describe your problem well, what's in this folder, and what type of data structure do you expect to represent it as?

Thomas Owens

OK. Let me start from the top.

Jimmy Hoffa

foo.txt, bar.txt, quux.log - you wanted text files and log files? Or?

durron597

5:40 PM

@JimmyHoffa yeah, cv-pls unclear what you're asking

Thomas Owens

I have 28 different file types, organized in some arbitrary way. These files represent one or more images and views. The relationship is that a view is made up of images. But the directory structure may or may not reflect this, so I need to scan each and every file (recursively from a specified starting point). However, I need to build some number of View and Image objects to represent each view and image that I come across.

Ampt

(I told you recursion was the solution)

Thomas Owens

As I scan each file, though, it may be part of an existing View or Image or I may need to create a new View or Image to hold it.

But until I've read all of the files associated with a particular View or Image, it may be in an incomplete state.

It seems like this should be a solved problem that's probably really simple.

Jimmy Hoffa

@ThomasOwens so you gather all the files, then apply a partitioning function to them: You have X in your name -> Go to Partition (view) X, after applying that to all files you will have N sets of files that have been partitioned by (name?) your partitioning function - which was written to separate files by their view.

Thomas Owens

@JimmyHoffa I can't rely on the name. I need to look at the binary content.

I would prefer to do that once, since the files are large enough and there may be so many that I can't keep the binary content in memory.

Jimmy Hoffa

5:46 PM

@ThomasOwens whatever. That's the job of the partition function, it's got business logic that knows how to decide the partition it belongs in.

@ThomasOwens you would only look at one file at a time...

Robert Harvey

@ThomasOwens I assume you know how to create the recursive structure that holds your file pointers, metadata, type and status?

Thomas Owens

@RobertHarvey Yeah. That's defined.

Jimmy Hoffa

public ViewIdentifier PartitionFile(string fileName) { /* figure out which view this file belongs in */ }
Dictionary<ViewIdentifier, fileName> partitionedFiles = allFiles.ToDictionary(PartitionFile);

Thomas Owens

How do I create my View or Image object, though?

I need to keep track of which ones I've come across and easily determine if a matching View or Image exists.

Ampt

hash table?

Jimmy Hoffa

5:49 PM

ohhh

no you want

Thomas Owens

With 1000-5000 Images?

It just seems like the lookup would grow insane slow.

Ampt

hence the hashing, right?

Jimmy Hoffa

allFiles.GroupBy(PartitionFile) this will return a Grouping<ViewIdentifier, string> which has a Key property of type ViewIdentifier and an IEnumerable<string> which is a collection of file names

Ampt

use the image name or identifier as the key?

Jimmy Hoffa

@ThomasOwens haha no. what? Psh. What do you think hashtables/dictionaries are for? Constant time lookup. They slow down with hash duplication.

Thomas Owens

5:50 PM

@Ampt Hmm. Yeah. I could use the View identifier and the Image identifier as the key.

I should probably create a wrapper around the four values that are used to uniquely identify an Image.

Ampt

I think one thing you want to be careful with here is collisions

probably choose a hashtable that has built in collision detection and mitigation

Thomas Owens

Yeah. Collisions would be bad.

Ampt

you don't want two sets of images grouped together

so after you calculate it, you should look at what's already there and make sure they both match

Jimmy Hoffa

allFiles.GroupBy(PartitionFileByView).ToDictionary(group => group.Key, group => group.ToDictionary(PartitionFileByImageIdentifier))

^-- Dictionary<ViewIdentifier, Dictionary<ImageIdentifier, string>>

Thomas Owens

This becomes easier since every file identifies both the View and Image that it belongs to.

I've got to run, but I want to quick prototype this today. This should work well.

Jimmy Hoffa

5:57 PM

oh you want a single read of the file -> public ViewAndImageIdentifier PartitionFileByViewAndImage(string fileName) where ViewAndImageIdentifier must be something that is a composite key usable for comparisons so if it's a custom class implement IEquatable<ViewAndImageIdentifier> interface on it and override GetHashCode() alternatively - just use a string delimiter and make it a composite string

durron597

6:12 PM

@RobertHarvey Did you ever get any swag for your 100k on programmers?

Ampt

@durron597 he celebrated coffee day extra hard that day.

durron597

@Ampt really? i thought it was just a coincidence

Robert Harvey

@durron597 Yes. I now have a cup with EnsureCoffee() code on it, and a Programmers cup.

And a few stickers. And a couple of T shirts.

Is this:

        CollectionItemType item;

        for (var ii = 0; ii < collection.Count(); ii++)
        {
              item = collection[ii];
              // Do something with item
        }

equivalent to this?

        foreach (item in collection)
        {
             // do something with item
        }

durron597

6:27 PM

@RobertHarvey Nice

Robert Harvey

They're big mugs, too. About 12 ounces.

Ampt

@RobertHarvey yes

durron597

@RobertHarvey I guess the diamonds here have swag too, I wonder how many they've made of some of the smaller graduated sites

@enderland Do you have The Workplace swag?

Ampt

the proper notation is for (MyClass myIstance : myList) {}

at least in java

enderland

@durron597 yeah, I think I got a tshirt when the site graduated (and a red stapler lol)

durron597

6:29 PM

@enderland So THAT's where my stapler went

enderland

29

Q: Workplace Stack Exchange - Top User Swag (With A Surprise!)

As a thank you for being awesome by working so hard to launch a successful site, if you are on page 1 or 2 of: http://workplace.stackexchange.com/users?tab=reputation&filter=all ... I'll be reaching out to you this week to get your information to send you a little care package. What's in this s...

discussion

Jimmy Hoffa

> Choose one language to learn: JavaScript, Ruby, or Python.

ugh

wth is this guy doing giving advice to people on learning to code when he's been doing it for...what, a year and a half? Maybe? Pfleh.

durron597

55 mins ago, by durron597

> Choose one language to learn: JavaScript, Ruby, or Python.

user20683

6:46 PM

@durron597 or Lua or Perl even

user20683

or Racket

Ampt

Or Java?

maybe?

no?

ok :(

user20683

@Ampt Note that the listed languages are all dynamically typed. You know what Java isn't?

user55340

Woo woo! Winning people over with Hudson plugins. Got one click deployment working for a project.

user20683

standard.co.uk/news/celebritynews/…

user20683

6:51 PM

Amazon signs the Top Gear guys

user20683

Also White Lasers:

user20683

asunews.asu.edu/20150728-worlds-first-white-laser

Jimmy Hoffa

@Ampt considering what you're doing right now, I think I'd be happy with batch scripting... (confession: I actually like batch scripting, it's truly surprising what you can do with it)

@Ampt any forward movement yet on the whole "I want a career not a pidgeon hole" goal?

user20683

@JimmyHoffa I once saw someone's post about how they effectively out speed Hadoop with Bash

Jimmy Hoffa

bash is gross, I said batch

bash is a seriously troubling script which people do awful awful things with

user20683

6:52 PM

@JimmyHoffa Macs don't come in batches

user20683

though soon that will change

Jimmy Hoffa

@WorldEngineer that's ok, mac's aren't meant to be useful, they're just Art; they're their to be looked at, and while providing no functional use whatsoever people pay large sums of money for them anyway.

durron597

@Ampt LOLCODE

user20683

@JimmyHoffa hence my soon to be windows box (with something akin to a real graphics card even)

user20683

@JimmyHoffa there are a few things they are handy for

Jimmy Hoffa

6:54 PM

@WorldEngineer boat anchor?

user20683

@JimmyHoffa frontend land

Jimmy Hoffa

Crash Different - The Original

►

user20683

that place beyond the howling maelstrom of Javascript and Photoshop

Jimmy Hoffa

@WorldEngineer myth. All that software runs on mac or PC, and the hardware is near identical between mac and PC

user20683

@JimmyHoffa outside of Iris, it's identical

user20683

6:56 PM

or it can be

Ampt

@WorldEngineer I'm not sure I agree with the idea of learning dynamic typing before static. I would think it makes error catching and debugging much harder on the coder

user20683

@Ampt not harder, just different

Jimmy Hoffa

@Ampt I'm of the mind type systems should be taught well before any language...

"This is a type, this is what a type is for, this is how it works, these are the types of relationships people can create with types. Relationship A is mutually exclusive with relationship B, but relationship C is available regardless of whether relationship A or B is chosen, but cannot exist without one of those two."

user20683

Windows 10 Privacy Defaults Guide

Telastyn

@RobertHarvey - no, not quite. In C# at least, if you're screwing with the collection, foreach is not viable. Also, the Count() is evaluated each loop, so if you're adding to it, the counter can go infinite.

There's probably also trickery with casting during the enumeration due to .NET 1.0 legacy stuff

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