/dpt/ - Daily Programming Thread

first for python :D

My erection

What's your favorite git hosting service /dpt/?

Pi has a finite number of digits.

Reminder: OCaml is your god. OCaml is your salvation.

>>52564337
Alright m8, keep up the pretence. It's pretty clear that you're an idiot.

>>52564419
The fact that you've never compared by address is clear sign you've never worked with any serious code

>>52564414
>/sci/

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154KB, 604x900px

What's your favourite programming language, /dpt/?

>>52564419
OK pajeet.

How can I declare the types of scoped constants in haskell?

Has-type notation doesn't seem to work inside a function.

>>52564437
>feminist
>funny
pick one

File: 1452960196836.jpg (54KB, 418x359px) Image search: [Google]

54KB, 418x359px

>>52564437
not this again

>>52564439
I really like Go. That said, I'm starting to get more and more annoyed by those fucking error checks the more I use it.

>>52564439
based php

>>52564419
lol this is ridiculous. Are you aware, assembly, the most fundamental language that isn't machinecode has compare instructions all over the place?

>>52564467
Go: all the flaws of C without any of its benefits, none of erlang's benefits beside channels. Add a set of custom flaws to the mix, and you have yourself a Go.

>>52564437
Man this shit sure triggers me

>>52564360
Lazily learning functional programming at a corporate internship where I baaaaaarley get any work

Life's gud

>>52564419
In a game, if you want to see if the item/enemy you're targeting is the same item/enemy something or someone else is targeting, you would compare by address. Comparing references should NOT automatically compare the values of the thing they're pointing to. That is idiotic and will leave people wondering why their code doesn't work. To say comparing by value is the only important way to compare 2 things is clear sign you've only ever dealt with small scripts

rate my bubblesort

void bubblesort(unsigned *arr, unsigned size)
{
    while (!is_sorted(arr, size))
    {
        unsigned i;
        for (i = 0; i < size - 1; i++)
        {
            int state = compare(arr[i], arr[i+1]);
            if (state > 0)
                swap(arr+i, arr+i+1);
            else
                continue;
        }
    }
}

>>52564514
>barley
I oat to report you for this.

>>52564525
Presumably, is_sorted is doing a full array traversal on each iteration, making this algorithm O(n!) in time complexity instead of the usual O(n2).

So it's fucked.

File: juu.gif (992KB, 500x376px) Image search: [Google]

992KB, 500x376px

>tfw people call me a noob for using Ubuntu

I don't want to spend an hour setting everything up in Arch, ok?

>>52564510
There're some neat features in Go like a GC, reflection, goroutines, channels, easy cross compilation and a static compiled ABI.
It's a shame that they made some horrible mistakes by not using generics (muh generic dynamic array) and a proper way of handling errors.

>>52564390
My vps

>>52564582
noob

>>52564582
It's faster to have a working arch than a working buntu.

>>52564525
Now do it using recursion.

>>52564565
is_sorted() returns 0 as soon as it finds an unsorted pair
worst case is it goes through the whole array without a hitch and returns 1.

>>52564582
ubuntu is fine, just don't use unity

>>52564611
Ok, mate.

>>52564443
Anybody?

>>52564609
>worst case is it goes through the whole array without a hitch and returns 1.

Hence why that step is O(n)

>>52564439
haskell :3

>>52564609
You could count how permutation you do each pass. If it's zero your list is sorted.

>>52564656
>>52564647
what's a better way to do it then?

int is_sorted(unsigned *arr, unsigned size)
{
    int sorted = 1;
    unsigned i;
    for (i = 0; i < size - 1; i++)
    {
        int state = compare(arr[i], arr[i+1]);
        if (state > 0)
            return 0;
    }
    return sorted;

How does this logic check out for a the Farmer, Wolf, Goat, Cabbage problem?

farmer = 8
wolf = 4
goat = 2
cabbage =1

        virtual bool isGoalState(){
            return (state & 8 && state & 4 && state & 2 && state & 1);
        }

        virtual int* succStates(){
            int *states = new int[8];
            int i = 0;

            if(!(state & 8)){
                //farmer is west
                if(( (state & 4) || (state & 2) ) && ( (state & 2) || (state & 1) )){
                    states[i] = state + 8;
                    i++;
                }

                if(!(state & 4) && !(!(state & 2) && !(state & 1))){
                    //wolf is west
                    states[i] = state + 12;
                    i++;
                }
                if(!(state & 2)){ 
                    //goat is west
                    states[i] = state + 10;
                    i++;
                }
                if(!(state & 1) && !(!(state & 4) && !(state & 2))){ 
                    //cabbage is west
                    states[i] = state + 9;
                    i++;
                }
            }

>>52564680
I left some code out

        virtual int* succStates(){
            int *states = new int[8];
            int i = 0;

            if(!(state & 8)){
                //farmer is west
                if(( (state & 4) || (state & 2) ) && ( (state & 2) || (state & 1) )){
                    states[i] = state + 8;
                    i++;
                }

                if(!(state & 4) && !(!(state & 2) && !(state & 1))){
                    //wolf is west
                    states[i] = state + 12;
                    i++;
                }
                if(!(state & 2)){ 
                    //goat is west
                    states[i] = state + 10;
                    i++;
                }
                if(!(state & 1) && !(!(state & 4) && !(state & 2))){ 
                    //cabbage is west
                    states[i] = state + 9;
                    i++;
                }
            }

            if(state & 8){
                //farmer is east
                if(( !(state & 4) || !(state & 2) ) && ( !(state & 2) || !(state & 1) )){
                    states[i] = state - 8;
                    i++;
                }

                if(state & 4 && !(state & 2 && state & 1)){
                    //wolf is east
                    states[i] = state - 12;
                    i++;
                }
                if(state & 2){ 
                    //goat is east
                    states[i] = state - 10;
                    i++;
                }
                if(state & 1 && !(state & 4 && state & 2)){ 
                    //cabbage is east
                    states[i] = state - 9;
                    i++;
                }
            }

            while(i < 8){
                states[i] = -1;
                i++;
            }

            return states;
        }

>>52564439
It's Idris now I guess, but it's nowhere near production ready at this point, so I'd have to go with OCaml for getting actual work done and Scheme as a close second.

>>52564609

void bubblesort(uint32_t *arr, size_t size)
{
    int sorted;
    int state;
    size_t i;

    do {
        sorted = TRUE;

        for (i = 0; i < size; ++i) {
            state = compare(arr[i], arr[i+1]);
            if (state > 0) {
                swap(&arr[i], &arr[i+1]);
                sorted = FALSE;
            }
        }
    } while (!sorted)
}

>>52564676

void bubblesort(unsigned *arr, unsigned size)
{
    int n = 1;
    while (n)
    {
        n = 0;
        unsigned i;
        for (i = 0; i < size - 1; i++)
        {
            int state = compare(arr[i], arr[i+1]);
            if (state > 0)
                swap(arr+i, arr+i+1);
                ++n;
            else
                continue;
        }
    }
}

>>52564676
Don't use that function at all. You know bubbles sort is done when it goes through the whole list without swapping.

>>52564676

template <class d>
void swap(d& one, d& two)
{
    d d;
    d = one;
    one = two;
    two = d;
}

//Works with Arrays and Vectors
template <class d>
void bubblesort(d &temp, int n)
{
    bool sorted = false;
    int i = 0, j = 1;
    
    while (!sorted) {
        sorted = true;
        for (i = 0; i < n - j; i++) {
            if (temp[i] > temp[i + 1]) {
                swap(temp[i], temp[i + 1]);
                sorted = false;
            }
        }
        j++;
    }
}

>>52564680
If you're going to do binary comparisons, then use the notation. Your code looks a mess

>>52564713
I guess this would be better with a do-while, but you get the point

>>52564733
are you talking about bit shifting? You can't do bit shifts if trying to change the bits the way I am.

>>52564694
>>52564694

virtual int* succStates() {
    int *states = new int[8];
    int i = 0;

    if (!(state & 8)) {
        //farmer is west
        if (( (state & 4) || (state & 2) ) && ( (state & 2) || (state & 1) ))
            states[++i] = state + 8;
        //wolf is west
        if (!(state & 4) && !(!(state & 2) && !(state & 1)))
            states[++i] = state + 12;
        //goat is west
        if (!(state & 2))
            states[++i] = state + 10;
        //cabbage is west
        if (!(state & 1) && !(!(state & 4) && !(state & 2)))
            states[++i] = state + 9;
    }

    if (state & 8) {
        //farmer is east
        if (( !(state & 4) || !(state & 2) ) && ( !(state & 2) || !(state & 1) ))
            states[++i] = state - 8;
        //wolf is east
        if (state & 4 && !(state & 2 && state & 1))
            states[++i] = state - 12;
        //goat is east
        if (state & 2)
            states[++i] = state - 10;
        //cabbage is east
        if (state & 1 && !(state & 4 && state & 2))
            states[++i] = state - 9;
    }

    while (i < 8)
        states[++i] = -1;

    return states;
}

>>52564766
I'm talking about using binary notation rather than 8 4 2 1

>>52564482

How useful is it to learn Assembly. I took a systems class at my school and I hated it, but mostly had to do with professor being a dildo. I took the second level and I loved it, but it was mostly C stuff and the prof was really good (hard assignments but gave good lectures and helped students along the way without giving out answers).

>>52564588
>no dynamic libraries
This is enough to stay the fuck away from go
>muh return-value errors
And this should kill any remaining supporters.

>>52564467
I want to try it out, but have no idea what I could make with it that is useful and that doesn't need third-party frameworks.

Same with C actually, I have wanted to play with it, but I don't want to just make shitty tutorial programs.

>>52564792
I don't think that will make that big of a difference. How hard is it to visualize 8, 4, 2, 1 in bits

Threadly reminder that you should not refer to the act of programming as coding. It is improper and makes you look like a 16 year old

You are a programmer, not a coder

Software Alchemist is GOAT
Developer is okay
Magician is okay
Software Magus is okay
Software Engineer is okay
Software Architect is okay
Code Guru is okay


Archmage is reserved for only the most senior of programmers

Writing in HTML and CSS is not programming, therefore it should be referred to as designing

>>52564713
won't this terminate on the first loop regardless of what happens?

>>52564796
Essentially useless outside of writing compilers and vulnerability analysis.

>>52564810
Doesn't matter what you think. You had 2 choices and you chose the shit one

>>52564819
I generally refer to myself as a Datamancer, due to the nature of my work.

>>52564819
here's your reply lonely looser

>>52564809
Most folk use Go for network heavy programs.
Maybe some crawler stuff.

>>52564819
If it's not Computer Magus, it might as well be called Rajesh.

File: 1443657082930.jpg (65KB, 567x561px) Image search: [Google]

65KB, 567x561px

>>52564819

>>52564824
How so? If any swaps occur, n will be a nonzero number by the time it reaches the top of the while loop again

>>52564680
>( (state & 4) || (state & 2) ) && ( (state & 2) || (state & 1) )
can be collapsed to:

(state & 6) && (state & 3)

>!(!(state & 2)
what's with the double negation?
might have made sense if you needed to force to be exactly 0 or 1, but since you're just testing the 'truthiness' of it it's not needed.

>>52564826
It's actually better because I don't need to use a different data type

>>52564437
I was with her until she said white man. Now I realise women in the workplace are the enemy.

>>52564846
I've seen it mentioned, yeah. Still have no idea what I'd do with that kind of stuff in my free time, but I guess it's a starting point.

>>52564877
6 | 3 == 7
so it could be further reduced to (state & 7)

>>52564439
Forth for the pure enjoyment of playing around in it (especially implementing it from scratch without even an OS or kernel).
C for getting practical things done.

>>52564588
>reflection
Not as awesome as you think. In fact type erasure and reflection are the shittiest way to make type generic code. AND the programmer has to do that unsafe shit by himself instead of the implementation handling it for him. Go is somehow worse than Java in that regard. They better add reification soon or I'm going to shoot myself.

>>52564903
The only people who use Go are those who enjoy 2k lines of backtraces that actually don't say anything when a connection closes unexpectedly.

>>52564912
>C
>getting practical things done
Choose exactly one.

>>52564894
You don't have to use a different data type for binary, what the fuck are you on?

>>52564909
>6 | 3 == 7
>so it could be further reduced to (state & 7)
No, that would be: (state & 6) || (state & 3)
which would fire if any of the lowest for bits was set.
(state & 4) || (state & 2) ) && ( (state & 2) || (state & 1)
means he wants either of the two upper bits AND either of the two lower bits, which is only 4 total combinations out of the 15 possible from 4 bits (yours would accept all 15 combinations).

>>52564923
I choose both.

>>52564916
It's always good to know what hipsters are using, even if it's shit.
It could even get good in a few years.

>>52564819
> I'm a code slinger
> My main language of choice is Hypertext Markup Language and Cascading Style Sheets, or HTML plus CSS as I've taken to calling it.

>>52564986
>It could even get good in a few years.
Not while pike's at the helm.

>>52564914
True, reflection is used in places where generics could've been a better solution. The interface{} is a dirty hack imo.
Why is it so hard to make a decent programming language senpai? C++ is std::ugly, C# is the pet of MS and D is too obscure.

>>52564923
You can get practical things done if you aren't an idiot.

>>52564925
How do you use bit notation? The only way I see is to use a new type or use c++14 which I can't.

>>52564858
Well I guess that's a better way of putting it.
Thanks anon!

>>52565017
So what are you doing here?

So does anybody have any idea why this code isn't working?

main ∷  IO ()
from ∷  String → [Int]

from = map fromEnum

main = do
    print "Enter message: "
    message ←  readLn
    print "Enter shift number: "
    n ←  readLn
    print $ map toEnum∘(+n)∘from message

>>52565011
literally 0b for bit and 0x for hex

>>52565010
Yeah, like hello world, and fizzbuzz, and high/low, and even, if you're an expert, perhaps heads or tails! What a fantastic language!
Now if you'll excuse me, I have real work to do, which involves performing expensive computations across 27 machines of 4 GPUs each.

>>52565011
Congrats, you're clinically retarded!

>>52565026
No problem, I'd just recommend rewriting it as a do-while and putting

int n = 0;

inside the do-while. It's much cleaner that way

>>52565031
>→
>←
>∘

>>52565079
Ignore the graphical-syntax sugar, it's there for readability.

>>52565048
>Now if you'll excuse me, I have real work to do, which involves performing expensive computations across 27 machines of 4 GPUs each.
How about 16 000 machines, each with two xeons and three xeon phis for a total of ~3 million compute cores?
It's running on a platform written in C.

Think I'll go watch anime.

Any suggestions?

>>52565048
I'd say the Linux kernel is pretty practical :^)

>>52565104
Dagashi Kashi is bretty gud.

>>52565104
C and Python or Ruby

>>52565001
Go has a good base: sane OOP, good GC, excellent routine scheduler and features, but the designers decided that compiler complexity outside of those areas is not acceptable and made the rest of the language shitty. I'm sure if someone forked Go and made 'Good' that it would be God's chosen language.

For right now, C++ is ugly and complicated, but feature-wise I think it's very good for a systems language.

how do i set up dlna on linux?

>>52565074
I tested both on an array of size 214748364 and their performance is nearly identical.
>is_sorted

real    0m0.410s
user    0m0.340s
sys    0m0.076s

>while (n)

real    0m0.414s
user    0m0.340s
sys    0m0.076s

>>52564529
not this shit a grain

>>52565169
sudo apt-get install minidlna

>>52564819
Code monkeys who glorify their shitty webdev jobs with those titles make me sick. I know someone who calls himself "Code Whisperer", after teaching himself basic Web languages and memeshit like node.js.

And "software engineer" is reserved for actual engineers.

>>52565031
define 'isnt working'

>>52565171
With an actual randomly generated array?

>>52565189
engineers are held liable if their creations collapse and kill people

software engineers aren't, because they're not really engineers

way to write a lua function out inside a table?

>>52565201
let me try that

i was just sorting garbage in memory

>>52565193
It throws compile errors no matter how I phrase it.
The code as posted gives:

Couldn't match expected type 'a0 -> [Int]' with actual type '[Int]'
Possible cause: 'from' is applied to too many arguments
In the second argument of '(.)', namely 'from message'
In the second argument of '(.)', namely '(+ n) . from message'

>>52565149
Go devs are completely autistic about compile time. Adding things like generics increase compile time and that's a no-no.
Another thing I find missing is a file scope for defining constants.

>>52565218
Like this?

{function(x, y) return x + y end, function(x, y) return x - y end, ... }

>>52565232
Here you go - the from function was tripping you up.

Prelude> map (toEnum . (+1) . fromEnum) "asdf" :: String
"bteg"

>>52565210
Whatever you say, code monkey. If software engineers were the same as your kind, they wouldn't get higher starting salaries than other engineering fields.

>>52564588
Generics are not a big deal for people writing actual programs because you simply don't care about making things generic.
For reusable libraries generics can be nice, but for libraries you can use code generation to stamp out the versions you need (you can bake it into the build/fetch part since you need to do at least that one extra step for getting 3rd party libs anyway).

>>52565316
this, put parenthesis around those functions separated by dots

>>52565246
D's generics don't slow it's compilation down. In fact, I'm pretty sure DMD compiles faster than Go's reference compiler.

>>52565103
>cpu
I laughed
>task that isn't strongly bandwidth-bottlenecked
You're hilarious!
>C
I bet it's python, but you call it C because cpython is written in C! Top C-uck!

>>52565115
The amount of vulnerabilities it has is very practical indeed :^) All thanks to C :^)

>>52565149
>Go
>sane OOP
>features
>let alone good features
>let alone excellent features
>good GC
This is what gotards actually believe

>>52565347
My biggest problem is the lack of a generic resizeable array. Writing programs, not libraries, rarely benefit from generics unless you're a Java developer.

>>52565375
it's not even a contest, dmd literally blows everything else out of the water.

File: java-c performance.jpg (205KB, 1181x792px) Image search: [Google]

205KB, 1181x792px

Why is C slower?

>>52565316
I understand what this code is doing, but I can't seem to work it into what I already have.

main = do
    print "Enter message: "
    message ←  readLn
    print "Enter shift number: "
    n ←  readLn
    --print $ map toEnum∘(+n) $ from message
    print $ map ((toEnum)∘(+ n)∘(fromEnum)) message

Results in literally pages worth of errors

>>52565276
I see, i'd like to do something like this:

table = { 
    x, 
    y, 
    run = function()
        print( x, y )
    end
} 

but it gives me the attempt to index a nil value error

>>52565399
The lack of OOP functionality makes it sane. Java style OOP is batshit insane.

>>52565437
>Java style OOP is batshit insane.

In what way?

>>52565427
gcc -O3 -march=native

>>52565427
>sublime turd
>UNREGISTERED
C is only as fast as you are in the head.

>>52565427
try gcc -O3

Also, you're counting startup time of the C binary, including library loading, whereas you're not doing it in the Java one.

>>52565201
> while(!is_sorted)

time ./bubblesort 
214748 ints allocated!
sorted!

real    2m6.845s
user    2m5.588s
sys    0m0.128s

>while (n)

time ./bubblesort 
214748 ints allocated!
sorted!

real    2m8.223s
user    2m8.084s
sys    0m0.004s

>>52565445
teh boilerplate m8

>>52565437
>java is the only oop language in the wooorld !111
Gonoreah, everyone!

>>52565427
You're not using equivalent timing methods

>>52564819
What about 'Analyst'?

>>52565377
>I laughed
You're laughing at the most powerful computer in the world?
Do you even know what Xeon Phi's are?
>task that isn't strongly bandwidth-bottlenecked
Which is why you need a good scheduler, written in C.
>I bet it's python
No, it's a few million lines of C.

>>52565210
Depends on the country meight.

>>52565386
No piece of software is going to be free from vulnerabilities, and that most definitely doesn't make it impractical.
How much am I willing to bet you are using Windows, which is also written in C?

>>52565445
Inheritance is rarely useful. The fact you can use interfaces combined with inheriting another class is pantsu on head stupid. Composition and proper design solves most of those cases. Everything is a method.

>>52565001
Haskell

>>52565489
Xeon Phi's are actually kind of crappy... but agree that C rocks.

>>52565503
>lol fuck inheritance muh gomposishun

Filtered.

>>52565429
That's just Haskell being Haskell
you gotta learn to understand those error messages

>>52565064
sounds like you need to release some tension. Go jerk off to some hentai because I'm assuming you don't have a girlfriend with a neckbeard like that.

>>52564360

Java related question: what is a good module to use for image manipulation, stuff like cropping, resizing, and editing photos?

>>52565489
I'm laughing my ass off. You're so desperate it's so cute! Be sure to inform yourself before posting though. Making yourself look twice the fool you are is not doing yourself any service.

>>52565559
java.nio

>>52565499
Windows is written in C++ because C is THE vulnerable language. Name one non-shit language that supports buffer overruns, use after free, and double free as FEATURES. You literally can't.

>>52565575
The kernel is C

>>52565539
It's true what they say, the tears of retards are a most delectable delicacy.

>>52565528
Inheritance is useful when you're dealing with a deep hierarchy like UI widgets and entities for game development. Using inheritance for the sake of tweaking the way a class works, is stupid.

>>52565520
>Xeon Phi's are actually kind of crappy
They are way more power efficient compared to GPUs, and keeping power usage down is one of the main priorities when scaling to the petaflops range.

>>52565322
oh look another eng major with buyers remorse

>>52565584
>backpedaling

>>52565594

I agree with you now, but that's not what you said initially.

>>52565429
>No instance for (Read a0) arising from a use of ‘readLn’
>The type variable ‘a0’ is ambiguous
>No instance for (Enum a0) arising from a use of ‘fromEnum’
>The type variable ‘a0’ is ambiguous
The compiler cannot infer the types in this case. You need to add type signatures.

main = do
    print "Enter message: "
    message <- readLn :: IO String
    print "Enter shift number: "
    n  <-  readLn :: IO Int 
    print $ (map (toEnum . (+ n) . fromEnum) message :: String)

File: 1451080352324.jpg (57KB, 576x436px) Image search: [Google]

57KB, 576x436px

>>52564582
>being on the bleeding edge after a month

>>52565607
Not the guy you were replying to, just pointing out that you're wrong. The kernel usually defines the language the OS is written in.

>>52564588
error values make user errors the default (in go you handle programming errors with panics)
exceptions make programming errors the default
i personally prefer the first, although some syntactic sugar for forwarding might have been nice
essentially, error values as monad (when implementing this one has to make sure that it is immediatly obvious when reading some function's code which function can return an error and which can't, and this is pretty damn hard to do in an imperative lang)

>>52565562
>this amount of projection and delusion
a few dozen gpus is consumer tier, people can run that in their garage.

>>52565488
Analyzing is not the same as programming.

>>52565598
>powerefficiency
>mattering
>compared to performance
Keep playing with your toys. Any realworld task would take over a year to complete on your magical cpu utopia machine. There's a reason everyone with an ounce of seriousness is using GPUs.

>>52565631
I spend most of my time writing programs.

>>52565629
>google is consumer-tier
OK bro.

>>52565503

>inheritance is rarely useful

- Design of GUI APIs makes extensive use of inheritance. Impractical to subclass a graphical component using composition.
- Wrappers around core behaviour (e.g., inherit from list and make it fire events when elements are added) are easier done with inheritance.

These two are just common use cases where composition is not too useful.

>>52565575
JFYI, C++ has all of those amazing "features" it inherited from C as well.

Windows is written in C. The C++ features that they support are pretty much limited to what you would get from a C API anyways, and are also entirely accessible from C.

File: 1451141337349.jpg (45KB, 716x717px) Image search: [Google]

45KB, 716x717px

>>52564819
>Code Guru is okay
>moonrunechan/baroo\ baroo/mfw.jpg

>>52565608
Poor wording on my side.
My point is that inheritance is usually not necessary and makes your code more complex than it should be.

>>52565680
In many cases GADTs are a much better solution than inheritance.

>>52565456
>dislikes sublime text
>then hates him that he hasn't bought it
I think you're the one fucked in the head

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171KB, 1000x600px

>>52565607
You don't know what that means.

>>52565435
x and y are nil, that's why. You don't need to declare fields in Lua table. What you are doing is making a list where index 1 is x (which if undefined is nil) and index 2 is nil, and field run is a function. Lua tables don't support 'this', which seems like what you are trying to do.

>>52565399
>pic related

>>52565594
>>52565608
Overriding is shit for "deep hierarchies".
Inheritance without overriding is what Go's type embedding is.

>>52565575
>Windows is written in C++
u wot?
Windows NT is written in straight C, and the WinAPI is C as well. Most of the MS apps and whatnot are written in C++ but using the WinAPi which is itself C, so it's barely any different.

>>52565664
The butthurt is amazing! Keep it coming please.

>>52565702
okay, that's all I needed to know

not a deal breaker

thanks

>>52565702
Gofags, everyone!

>>52565611

message <- readLn :: IO String

doesn't actually work though, because it apparently looks for a binding to message (causing an error when said binding obviously doesn't exist).

>>52565713
Wrong.

>>52565456
>sublime turd
>probably a vimtard
>not using magnetized needles to flip bits in the hard drive

>>52565752
Thanks for coming to /dpt/ today, you made a difference!

>>52565721
>>52565752
You're not even trying anymore

>>52565627
>although some syntactic sugar for forwarding might have been nice
Exactly. Java has the throws keyword. It would be nice for Go to have something similar.

>>52565771
>>52565752
Samefag.

>>52565635
>powerefficiency
>mattering
It's pretty much the number one engineering priority when designing big data centers.
Why do you think northern Sweden and Finland has become such attractive targets for data centers? Cheap electricity and good cooling.

When you run a home made GPU setup in your home, sure you go maximum performance, but you can not viably scale that beyond maybe a 100 teraflops.

>Any realworld task would take over a year to complete on your magical cpu utopia machine.
These "cpu toys" are literally several orders of magnitude more powerful than your little "eXtreme g4ming GPU H0M3 CLUSTER".

>>52565752
https://msdn.microsoft.com/en-us/library/bb384843.aspx
>The Win32 API (also known as the Windows API) is a C-based framework for creating Windows applications.

>>52565644
The people who write job listings don't necessarily know the difference.
See http://programmers.stackexchange.com/questions/140561/

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>>52565779
>you tried

Low quality bait.

>>52565792
>I get all my computer science information through The Guardian
t. you

>>52565793
I'm sorry you're retarded, but actually I'm not sorry.

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fuck
I have 16k gps locations (long and lat) on a map(one state), there is same distance between each point. On the map it looks like a big grid 4k * 4k gps locations.

Now for a given gps location I have to find 4 gps location that make smalles square around given location 2 * 2 from 16k * 16k gps location.
I have a text file with 16k location but they are not in order.

Each gps point it made of lat and log and I have no idea how should I search, first find nears long, then lat? but how to find other points?

Guys guys we are supposed to be friendly here since we are interested in the same stuff.
GROUP HUG !

>>52565773
throws works with exceptions, exceptions make programming errors the default (the "throw" operation is costly because you need the stack trace, and it's often generated redundantly or even way too deep into the call stack)
"throws" causes the exact issue i mentioned: you cannot distuingish properly between functions that return errors and functions that don't anymore.
this means that you have to traverse the call tree all the time and read documentation just to find out which functions may actually cause errors.

>>52565851
Go back to /mlp/ faggot.

>>52565845
You also have white dots where lines intersect.

>>52565852
Not sure if retarded or just pre-
>go programmer
Oh.

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Well I changed 'readLn' to 'getLine' and suddenly all my problems went away.
Huh.

Well either way I'm not complaining, as I finally got my shitty and broken Caesarian Shifter completed. Pic related is the beauty of clean Haskell.

>>52565845
Build an R-tree.

>>52565851
We don't like the same stuff.

Lots of people here like Go, Python and JavaScript.

They're terrible languages.

>>52565824
>I get all my computer science information from linustechtips
t. you

>>52565869
You just need a human touch.
Its ok anon, /hug

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Can /dpt/ tell me about Python? I am new to Programming and I want to learn Python for my first language, as I have heard that Python is the best language for beginners. Any tips for a newbie programmer?

>>52565895
No, I actually do that stuff I mentioned for a living. Nice projecting though.

>>52565893
Python is used in top tier info sec and pentesting (also pure good old hacking).

>>52565902
It's shit and will teach you really bad practices for later on.
Start with C++.

>>52565902
http://haskellbook.com/

>>52565916
Not sure if this is bait or not. Isn't C++ A Horrible language to learn for beginners?

>>52565921
Fuck off.

>>52565902
>An interpreted language best for beginners.
Where the fuck did you hear that?

>>52565913
And?

It's still a shit language.

>>52565913
Is it really? I'm going into infosec, so would it be a good idea to learn it for that?

>>52565916
This.

>>52565936
Says...you? A literal nobody?

>>52565931
The internet.

>>52565936
If Python is a bad language for beginners, what language is good for newbies then?

>>52565945
I cant tell if I am being trolled or not.

>>52565564

thanks

>>52565929
The python beginner is bait. Plain as goddamn day. As are the majority of the responses.

/dpt/ is fucking retarded at times.

>>52565929
You'll be a better programmer in almost every language in mainstream use, including Python, if you learn Haskell.

>>52565957
Pascal.

>>52565929
>Not sure if this is bait or not. Isn't C++ A Horrible language to learn for beginners?
Not at all. It was my first language.
The problem with Python and other 'popular' first programming languages (such as Visual Basic or Java) is that they're really, really abstracted, so you're not actually learning how to program, you're just learning how to program in that specific language.
C++ is close enough to the hardware that you actually learn how the computer handles things, which means you can better apply that knowledge later when you're actually doing higher level work in C# or whatnot.

Also it's still one of the most used languages out there.

>>52565969
The only retard is whoever falls for the python meme.

>>52565974
what the fuck did you do to 4chan

>>52565957
ML

>>52565971
>>52565969

So then if Python is low quality bait, what language is good for beginners?

>>52565978
Is C good enough?

>>52565984
Says a literal NEET nobody.

>>52565748

test
"Enter message: "
"Help"
"Enter shift number: "
2
"Jgnr"

Works for me. I'm guessing you didn't realize that readLine needs "'s to parse a string. Here you go, this is what I think you want, using getLine over readLine and putStrLn over print (we can also drop the type annotations):

test = do
    print "Enter message: "
    message <- getLine 
    print "Enter shift number: "
    n  <-  read . getLine 
    putStrLn $ map (toEnum . (+ n) . fromEnum) message
                                                       
"Enter message: "
asdf
"Enter shift number: "
3
dvgi

>>52565902
Depends on what you want to do later. If you just want to learn to program something and be able to automate simple things, do Python. Can do machine learning, maths, web development and other fancy things that are in the mouth of everybody now.

However, if you want to be a programmer and learn serious programming, start with C. Understand what's going on, what's a compiler, how does memory work, etc. Then move on to something "enterprisey", such as Java, C++ or C#, to learn OOP design. Then go to Haskell and learn a bit of functional programming and paradigms (you will not use Haskell for anything, but some ideas in it are actually pretty nice and will improve your code in other languages). Now you're a programmer and can learn whichever language you want.

>>52565984
WAY too obvious jackass.

>>52565957
OCaml.

>>52565999
Haskell

ML in a pinch

C is good to know but doesn't give you the same sort of transferable skills

>>52565999
C is good, but honestly a little TOO low level. It's so barebones that it lacks some features that essentially every other programming language has, such as a 'string' datatype (yes you can easily replicate strings in C, but a beginner may not realize this) or whatnot.

>>52565852
I'm not into functional programming, so I won't touch the monad subject.
>you cannot distuingish properly between functions that return errors and functions that don't anymore.
From a debugging perspective, that's a big problem. It can be solved by adding logs or using a debugger.
Otherwise, why would you care who threw the exception? Let's say you catch a SocketException. Why would you care who threw the exception? You most likely want to revert all your actions and notify the user that something went wrong while networking.

>>52566006
Sorry, THIS is what you want:

main = do
    print "Enter message: "
    message <- getLine 
    print "Enter shift number: "
    n  <- readLn 
    putStrLn $ map (toEnum . (+ n) . fromEnum) message

>>52566005
Keep projecting. I bet you like C.

>>52566009
>/g/,ladies and gentlemen
this is seriously worse board than /pol/ and all homosexual boards

>>52565954
The point of an anonymous imageboard is that its users are anonymous

Also it doesn't matter who says it, Python is shit, enjoy your GIL, shitty type system, and whinging about having to change code in order to migrate to 3.x

>>52565911
>No, I actually do that stuff I mentioned for a living.
hohoho
The fact that you don't think C is used for super computing was a dead giveaway.

>>52566034
I bet you stash your own cum in little jars around your pc,putting little name stickers of your favorite ponies on them and taking sip every time you shitpost on 4chan.

>>52566049
kill yourself clueless neet, give your parents a break

So, /dpt/ is pretty much telling me that every single programming language is shit?

Well fuck.

I just wanted to know what the best language for beginners was ;_;

>>52566067
The fact that you think people do HPC in software is a dead giveaway that you get your information from The Guardian or other tabloid-tier outlets.

>>52566091
guido pls

>>52566098
start with java, then learn C++ if you want to get more autistic

https://docs.oracle.com/javase/tutorial/

>>52566098
>So, /dpt/ is pretty much telling me that every single programming language is shit?
That's /g/ for you.
Having a problem? Your fault for not doing the exact same thing as every other anon 100% of the time.

>>52566098
Any of them is just fine. Just don't think ONLY one of them will teach you enough for more than fizzbuzz.

>>52566098
serves you well when you are trying to get serious info on a fucking 4chan.

>>52566098
OCaml.

>>52566133
Lesson learned.

>>52566098
Haskell

>>52565635
>>52565792
doesn't it depend on the specific task which is more efficient out of CPU vs GPU?

you are all scumbag cynical imbeciles

>>52566167
spoiler: yes. Almost every task is GPU these days but some workloads (usually static operations performed on very large amounts of data, as opposed to dynamic operations done data-chunks at a time, in particular those where synchronizing is expensive) can benefit from using large cpu farms instead.

>>52566098
Just pick any high level language. It really doesn't matter.
Python is a nice language for a beginner. C# and Java are also good languages.

>>52566039

thanks for your thoughtful argument

>>52565929
>Isn't C++ A Horrible language to learn for beginners?
Only if you believe the memers who say starting with C++ will ruin you for life.

>>52566189
Thanks, Anon.

>>52565174
I like your wheat

>>52566189
>Python is a nice language for a beginner.
It's only really good for getting used to basic control flow constructs.

>>52565999
Java is pretty damn good for begginers bro.

In the end, it's more important your skills about programming and stuff like recurssion, divide and conquer, data structure, logic than what language you use.

only autist think language really matters.

>inb4 some retard answer
you know the language doesn't matter faggots, you could literally write an OS in javascript retards.

>>52566204
python is absolutely fucking disgusting i'm not kidding. please just learn java or C#

https://en.wikipedia.org/wiki/Duck_typing#Criticism
http://programmers.stackexchange.com/questions/15468/what-are-the-drawbacks-of-python
http://software-carpentry.org/blog/2012/02/why-not-use-python.html

>>52566225
Isn't that the definition of a beginner?

>>52566239
No, that's the definition of a retard. A beginner masters that shit in a few hours at the latest, assuming they have sub-par intelligence.

>>52566239
no you learn basic control flow literally on your first day and then it applies to all imperative languages (so you don't need to use python specifically). there is so much more to learn

>>52566228
you could write an OS in Javascript, however you would probably lose sanity in the way and it would probably be absolute crap.

>>52565845
If the grid is aligned with the lat and long lines, and it covers a small enough area that the earth's curvature doesn't matter, you don't need the entire file. Using just one corner and the grid size you can get the 4 surrounding locations on the grid.

a = floor( (x-left)/grid_size ) * grid_size;
b = floor( (y-top)/grid_size ) * grid_size;
c = a + grid_size;
d = b + grid_size;
l1 = (a, b);
l2 = (a, d);
l3 = (c, b);
l4 = (c, d);

>>52566237
>>52566247
>>52566257
THANK YOU

I get it, some people are emotionally invested in Python, but it's not a good language.

>>52566270
On the other hand, mirageos shows that writing an OS in ocaml is no problem.

>>52566189
This. Just google the top 5 most popular languages and pick the one you think has the coolest name.

>>52566287
>how to get stuck in a deadend job for the rest of your life in 1 easy step!

>>52566257
Not everyone is Edsger Dijkstra tier.
What you say is that anon should just dive into C and man up.

>>52564801
>Not appreciating exception-free code that has no chance of jumping back up the call stack on what is usually an unexceptional case

>>52566287
http://spectrum.ieee.org/computing/software/the-2015-top-ten-programming-languages

the ones in the top 5 on this list except for python are acceptable

>>52566321
>pretending the past 50 years of CS research doesn't exist to justify garbage-tier choices in a "modern" language

>>52566302
what would you do Mr.Nextbillgates?

>>52566270
yeah, but he asked if it was good for LEARNING THE BASICS

any language will be good for a begginer because the foundamentals are more important than the syntax you write.

>>52566320
if you take longer to learn you definitely shouldn't be using python anyway. python is a terrible learning environment.

>>52566367
>once again /g/,ladies and gentlemen
>teh real "programmers"

>>52566367
javascript and python hide types from the user and you don't have to specify types. how is that good for the beginner? any programmer has to learn types and it's not hard at all so don't try to say that it isn't essential.

Is Nim's compiler actually a compiler?
If it goes from Nim code -> C code -> binary executable, isn't it a transpiler?

>>52564437
what is reversing a tree? rotating it? or simply flip left and rights?

>>52566418
take a binary tree and switch the lefts and rights

>>52564706
nice undefined behaviour there kid

>>52566367
The basics is more than just control flow.

>>52566440
That's a four line problem.

>>52566371
Python is comfy to learn the absolute basics. The interactive shell is pretty good for simple doodles.

>>52566440
so the problem is pretty much just traversing a tree?

>>52566462
>>52566482
yep

just don't expect an entitled female """"""""software engineer"""""""" to be able to do it

I wish I was pajeet.

>>52566381
>>52566406
>>52566445
yeah, it's not like you could you know FUCKING SWITCH TO ANOTHER LANGUAGE after you learn the basics of flow control.

fucking retards

>>52566501
>
granted

>>52566441
where?

>>52566512
Unnecessary complexity, confusion and overhead when trying to learn programming.

>>52566512
would it kill you to do it in java?

https://docs.oracle.com/javase/tutorial/java/nutsandbolts/flow.html

>>52566025
i don't care about who *threw* an exception, i care about what *might throw* an exception.
when i'm reading the code of a function i want to know what it does in all cases. "throws Foo" tells me that somewhere, one or multiple of the things in the function, throws an exception of type Foo.
now, when reading this, this barely helps me with anything, if i want to properly understand the control flow of the function, like when it returns, i have to check all the functions this function calls for their type signature to find out.
if this kind of pattern is used everywhere where you have errors, then the code becomes very tedious to reason about and to read, because errors are an important part of the behaviour of a function.
this is one of the reasons why the throws declaration isn't used that much in java compared to the throws statement.
in languages like haskell you only group function calls of functions that really return some sort of error.
you get rid of the boilerplate for error checking in functions executed after each other.
because only functions that return an error are grouped, you can distinguish between functions that return errors and functions that don't.
this however isn't that easy in an imperative language, because functions aren't the only things that matter.
so far i haven't seen any imperative language that properly solves this issue (error values / user errors the default, syntactic sugar for forwarding, no loss of context info when reading).
i'd argue that in an imperative language you'd mostly still have to be explicit about which function returns an error, although maybe with less writing effort and noise than go requires.
then again, there are lots of other aspects to consider as well in this regard that i might not consider, so i might be missing something obvious as to why such a "short explicit forward" might not be that great for readability either.

>>52566098
Well, quite a lot of the people here also seem to believe that they are smarter than the designers of the languages they are criticizing, so I wouldn't take a lot of what is being said here seriously.

>>52566544
In Haskell you can even easily accumulate errors with Validation.

>>52566532
yeah, it's not like learning that bool boolean is the same fucking shit.

it's not like the core concepts stay the same.

>>52566540
why do you fags keep bringing java everytime?

>>52566562
a lot of people are smarter than the designer of python

>>52566573
kill yourself idiot

>>52566562
Almost everyone is smarter than guido or aqar or what's his name.

>>52566570
sure, but as i said, it sadly doesn't come together as nicely in imperative languages.
also, for some cases i'd argue that a bit of redundancy is better than an abstraction.
while functional languages are very powerful, they make it very easy to write highly abstract code, and that isn't always good in regards to understanding the program.

>>52566573
It's fine when you have some experience, but when you're starting out, it's extra overhead to remember that you would learn more efficiently without.

>>52566440
Now the Homebrew dev was asked to 'invert' a binary tree, i.e. leaves become a list of roots, every node has only one child and children have two parents. Like a family tree.

I doubt half of /dpt/ could do this.

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GROUP HUG !!!

>>52566734
>>52566734
>>52566734
NEW

>>52566614
dont doubt it. I dont even fully understand the problem desu

>>52566614
Invert usually means left <-> right.
Eitherway,

let invert = function
 | {(parent), (left, right)} -> {(invert left, invert right), (parent)}
 | {(parent), ()} -> {(), (parent)}
 | {(), (left, right)} -> (invert left, invert right)
 | {(), ()} -> () 

maybe?

>>52566692
>mov
>35%
good god
>push 10%
>pop 4%
what?
>#12-19 are all 1% each, probably slightly less
>rest consume 11%
...

This arch makes me cringe.

>>52566796
Your idiocy makes me cringe.

Bahhhh

>>52566767
>Invert usually means left <-> right.
That's rotate. He said it meant make roots leaves. Just with terrible terminology because he doesn't understand binary trees at all. No wonder he didn't get the job.

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I want to try to make a Pokemon clone to try to learn and understand FP but I can't think of a way to update values without mutation. Whats the most functional way to handle damage and stat changes?

>>52566873
You're wrong. See for instance https://leetcode.com/problems/invert-binary-tree/

>>52566900
Use an explicit environment:
doUpdate param1 param2 world =
...
{world with something = somethingNew}
so doUpdate is T1 -> T2 -> World -> World

>>52566873
That wouldn't even be possible with every tree.

>>52565845
4k * 4k = 16 million

126.5 * 126.5 = 16000

git gud

>>52566912
>"to min-max a tree, ascending to descending"
From Howell's Twitter.

>>52566941
How not? This is assuming binary tree, as the tweet said.

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>>52565700
he probably meant that the guy should have pirated it instead of being a fucking vagina

>>52566996
That's not even remotely related.

>>52567041
His explanation was shit. He is a bit of a home-grown project-oriented type. They usually don't know shit outside of how to patch together already written code. He probably even meant turn a min heap into a max heap, but doesn't know the difference between a heap and binary search tree.

>>52566098
The problem with languages that just werk™ is that they're so easy, they make anything else seem fucking impossible afterwards.

Ask any CS lecturer who's has students who started off with basic.NET, they get so used to everything being piss easy and verbose they cant do anything more complicated than fizzbuzz.

If you start with a babby language, the learning curve starts off really easy, and then jumps up drastically when you hop to a practical language.
Whereas if you learn in something a bit trickier, the initial learning is hard but then switching to any other language is relatively easy.

>>52565663
- How about delegation instead of inheritance for the GUI framework?
- I'd argue that with the list extension you end up writing the same set of methods, but in one case you wrap your basic list and in the other you call the parent's implementation, so they seem roughly equivalent.

So I have a char *filename and I want to copy it to create a new string without the actual filename (its preceding directory)

e.g. /usr/bin/kek.sh --> /usr/bin/

I can get a pointer to the last slash using strrchr() and of course I have a pointer to the start of the array.

Is the best way to do this by allocating space by subtracting the first char pointer from the last slash pointer (plus 1 for the terminator), use memcpy then insert a terminator at the end?

>>52568291
>man 3 dirname

>>52568358
neat thanks

>>52566796
Have you used assemvly before? Half the time you have to move shit so you don't trash another register, enabling paging for example

>>52564437
Okay, see, in most cases I'd say she has a point. Most of programming isn't implementing neat algorithmic tricks, it's careful implementation of high-level logic, testing, covering edge cases, documenting, and integrating with the rest of the product.

In this case, though, there isn't any excuse. You take the root, return early if it's null, swap left and right, recurse for left and right. If one understands what a binary tree is and what it means to invert one, and there isn't any gotcha trickery going on in the wording of the question, this should be done in 5 minutes or less.