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Disadvantaged youth to young independent adult wanting to finally pursue his dreams by Wizzle710 - Sun, 22 Oct 2017 23:02:04 EST ID:YAuFJPxx No.37221 Ignore Report Reply Quick Reply
File: 1508727724535.jpg -(49540B / 48.38KB, 480x852) Thumbnail displayed, click image for full size. 49540
Hey everyone. So this is the long and the short of it.
For as long as I can remember, I've wanted to be a computer programmer, work with computers, do really geeky stuff with technology. I remember at 12 getting a cracked version of Macromedia Flash and teaching myself how to animate, and also trying to teach myself HTML and CSS. Well, my piece of shy father has been in prison since I was 7 and my mom had five kids, so I really didn't exactly get to pursue my dreams while my mom lost her house, and all of us kids had to get jobs and go stay with friends or family members because she couldn't afford to house us and support us all through school, and I was kind of a bad kid and a slacker and got kicked out of school, so I never even considered a scholarship was kind of out of the equation .
I still want to go to school and get a job sitting on my computer all day doing nerdy interweb stuff, where should I get an education? How can I get help paying for it? I want to be a success story and not the bitter shell of an abandoned son who gave up on his creative dreams and ended up as a cook making $10 dollars an hour.

Im 25 and want to get an education and become a computer programmer or work in cyber security or something. I would like some recommendations as to where to go and how to get financial assistance.
7 posts omitted. Click Reply to view.
Jarvis Clayworth - Wed, 22 Nov 2017 18:06:55 EST ID:5N3VHd+T No.37238 Ignore Report Quick Reply
OP, internships are hard to come by. I live in NYC and with 2 years education and loads years of freelance exp, I have yet to find one myself.

People who have connections seem to always suggest it, which is kinda unfair.

Anyways, for learning purposes, community colleges offer pretty good associates' in Programming and/or computer science.

If you're like me and hate math, a computer science degree is probably not the best to chase, but programming or telecom or information systems management paths would be adequate.
Martha Tillingcocke - Mon, 27 Nov 2017 03:38:05 EST ID:HH6lED9y No.37242 Ignore Report Quick Reply
I just wanted to say, if you're low income (which it sounds like) you should consider going to college because federal grants will cover most, if not all, of the tuition price.
This may vary state to state (I assume you are in the USA), but for my first bachelor's I did not pay a dime because I was considered low income as well.
Keep in mind the assistance is not forever. Where I live I believe the max is seven years of assistance or until you get your first bachelor's. With that said, you should try to finish community college as quickly as possible, so you can transfer to a four year university and not worry about the aid running out.
Good luck and it is possible!
Martha Tillingcocke - Mon, 27 Nov 2017 03:43:02 EST ID:HH6lED9y No.37243 Ignore Report Quick Reply
1511772182901.jpg -(958965B / 936.49KB, 1405x1405) Thumbnail displayed, click image for full size.
I just read the tl;dr where you ask about getting the assistance. Most schools have a financial aid office where you can get more information to apply. Ask lots of questions because any worker you interact with is going to want to do the minimum amount of work and send you on your way ASAP, whether or not your issues have been addressed. This applies to academic counselors as well. You are your own best advocate, remember that.
Cyril Bunforth - Wed, 06 Dec 2017 13:46:15 EST ID:FfnIApJC No.37251 Ignore Report Quick Reply
Apply to four year universities in your state. In-state tuition is a huge cost saver for most people. Join the one with the best Computer Science or Computer Engineering department that accepts you. Go to their finical aid office. They will help you with grants and loans.

If you graduate with CS or CE degree the loans will be worth it as long as you keep it under a hundred grand.
amydewkiss - Sat, 24 Feb 2018 02:05:34 EST ID:TLIaEAm5 No.37452 Ignore Report Quick Reply
Just get a job coding. No education needed. Google that shit and get work done. Apply to all the things. Wander the earth with nothing but a laptop, sleeping bag and a copy of Structure and Interpretation of Computer Programs

Somebody please explain interfaces in C++ by Jack Pittshit - Thu, 22 Feb 2018 15:54:59 EST ID:kBelsIZm No.37445 Ignore Report Reply Quick Reply
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I have a question.
I've done something similar to the example on this page.

What they've got there is a virtual class that's called Shape. And then a load of derived classes called things like Rectangle and Circle etc.

Then the go
Rectangle rectangle = new Rectangle();

What I can't see is a way to declare a variable of type Shape. I don't care if that winds up a Rectangle or Circle because they both will implement the interface. How can I do the following?

Shape shape = methodThatWillGiveMeRectOrCircle();

My compiler can't compile that method. It says:
> error: return type 'Shape' is an abstract class
Jarvis Wesslelure - Thu, 22 Feb 2018 23:07:30 EST ID:8hwK1pxu No.37447 Ignore Report Quick Reply
You have to use pointers.
Shape* shape = methodThatWillGiveMeRectOrCircle();
cout << "Totalarea: " << shape->getArea() << endl;
delete shape;
Martha Drellyway - Fri, 23 Feb 2018 04:51:38 EST ID:kBelsIZm No.37448 Ignore Report Quick Reply
That did the trick, thanks for pointing that out.
Can you explain to me why a pointer works here?
From what I understand, an int* can't just be assigned to a char* or void* without being explicitly cast so why is this different?
Rebecca Dumbleshit - Fri, 23 Feb 2018 23:50:53 EST ID:8hwK1pxu No.37450 Ignore Report Quick Reply
That's just how polymorphism in C++ works.

A Rectangle IS A Shape so it can always be safely cast implicitly.
While a Shape may not necessarily be a Rectangle so it has to be explicitly cast.
Wesley Furringnet - Sat, 24 Feb 2018 01:37:47 EST ID:BW3MomrQ No.37451 Ignore Report Quick Reply
You might be able to use references here too, but if that works then it's only because references are just pointers with nice syntax under the hood.

C++ Templates beyound trivial stuff by Nell Nagglefot - Sat, 02 Dec 2017 15:40:10 EST ID:9QSfnS0r No.37248 Ignore Report Reply Quick Reply
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What's the deal with C++ templates?
I'm looking for explanatory videos on it that is reasonably well produced
(not some autistic dude rambling to a screen recording)

Doesn't have to be a video though if it's well written. All explanations I've found so far don't give me any reason of why to use them at all (instead for instance method overloading)

Some time I'd need to for instance loads of static data that I could define by hand but still would like to take advantage of encapsulating things that resemble state machines in classes.
I use C++ for microcontrollers, never on a PC and some times access to hardware can't be done inside a class the straight forward way, like storing pointers to a hardware pin, timer register, etc... inside anything non-static.
Nicholas Banningpat - Sat, 02 Dec 2017 19:30:43 EST ID:v79vrqu4 No.37249 Ignore Report Quick Reply
Templates are about generics and generics are about types. You should understand the type system and how generics work if you want to call yourself a C++ programmer, but that's not to say your embedded code will suffer if you don't.
Nathaniel Clublingson - Sat, 02 Dec 2017 20:00:31 EST ID:BW3MomrQ No.37250 Ignore Report Quick Reply
For embedded code, you probably don't need templates for much. Maybe if you have 8, 16, and 32-bit data types you could write code that could use any of those interchangeably, but I don't think it'd be as useful for you as for someone writing for more flexible systems.
James Brocklecocke - Fri, 23 Feb 2018 16:55:05 EST ID:9QSfnS0r No.37449 Ignore Report Quick Reply
OP here

Somebody did make a video yesterday showing off code that does the thing I posted about, namely template programming for embedded.
https://www.youtube.com/watch?v=A_saS93Clgk ... if anyone is interested

A ridiculous sequence of courses by Doris Blatherstock - Sun, 04 Jun 2017 02:38:16 EST ID:HC1vVHLz No.37033 Ignore Report Reply Quick Reply
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Hello, I made and actually did all this (including the 'grad level' research electives, except for the coding theory book)

It's easier than it looks, it took me 3 years to do that. I did it about 3-4 hrs a day at first but then everything kind of snowballed and I finished it with only 1hr a day after the first year. These days I'm finishing The Art of Computer Programming series, I'm done up to book 4A and doing 4B draft at the same time. I just do it 20-30mins a day.

I cannot shill TAOCP enough, it totally changed me from amateur to professional computer scientist by just doing hundreds and hundreds of exercises. 20mins a day, for one year, it's all you need for the first book. Anyway, pick and choose what you want from this list and enjoy

I make money from cloning shopify apps, and I work P/T on https://turtle.ai/ though much more infrequently these days. I started out shilling myself on elance (now "upwork") as a jr developer and literally taking jobs from 3rd world countries for less than I would spend on lunch. I also work 2 days a week at my local university doing "ML" (statistics) for a cancer research lab making peanuts but it's research, and fun to do, and I don't need the money. The book in that above link, "Parallel and Sequential Algorithms" was directly responsible for the lab hiring me. Anyway anons I'm here to tell you to try this have a good day.
18 posts omitted. Click Reply to view.
Beatrice Mimbledatch - Thu, 26 Oct 2017 13:01:23 EST ID:VU0UgEAS No.37225 Ignore Report Quick Reply
hey opcan you repost that online linear algebra resrouces? I see you edited on the 24th and that really rustles my goddam jimmies man
David Dingerhall - Fri, 27 Oct 2017 16:27:58 EST ID:FXkQatto No.37228 Ignore Report Quick Reply
nvm found it, just pls don't delete your github history. Bookmarking what I can, but I don't want to lose anything
Alice Blundersine - Sat, 11 Nov 2017 22:16:46 EST ID:oPY6s1zJ No.37231 Ignore Report Quick Reply
OP will u fukn respond u jolly african-american

make a similar curriculum but for math, pls.
Sophie Dungerwadging - Thu, 23 Nov 2017 03:37:00 EST ID:x6K3CZQk No.37240 Ignore Report Quick Reply
This thread persists!

I'm pretty much terrible at math compared to the people at the lab I work with. Here I give the advice https://functionalcs.github.io/curriculum/#sec-2-4 the best way to learn math is to just find a paper or a book you want to understand and start doing it, looking up things you don't understand as you go along. Then as you progress through the exercises eventually you will just get it, well get it enough so you can use it correctly in an applied way. I did this when I first learned asymptotic representations such as big-oh/theta/ and big omega for lower bounds. It required a background in basic single variable calculus which I didn't have, so I picked up a calculus book and read it until I could follow the text on O(f(n)) approximation and until I could finally use Euler's summation formula to approximate finite sums. This led to learning about integrations, Bernoulli numbers/polynomials, derivatives, limits, all elementary calculus. I was terrible at proofs as well until I read VanDrunen's book on Functional Programming w/discrete mathematics which put it all together for me. Before that I was terrible at induction until I read Knuth's chapter on it despite working on numerous exercises and books on proofs before I came across Knuth's books. I guess you should just jump in and try the Mathematical Preliminaries chapters in The Art of Computer Programming, Vol I 'Fundamental Algorithms'. You can use libgen to get a pdf or buy a used copy anywhere, then when Knuth does some magic you don't understand with the notation summing a pile of subscripts and negative exponents or deriving rules from bracket notation look up directly that material in some elementary text (Knuth also tells you often where more information can be found, often referring T. Apostol or Hardy books by page number and volume). For elementary texts I used "What is Mathematics" by Courant and Robbins and Axler textbooks, since Axler works through every second problem and shows you the complete solutions instead of just providing an answer. I also asked a lot of stack exchange questions and shit posted my elementary problems on /sci/.

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Sidney Gorringwack - Thu, 22 Feb 2018 20:40:31 EST ID:Tfi7s7JZ No.37446 Ignore Report Quick Reply
OP, listen here buddy, you ought to make your presence known on stormfront.org/prog. Or better yet, some sort of blog where lower level lifeforms like myself can follow and pick ups morsels of knowledge, resources and ideas here and there.

I've been following your guide since it was just drunken outlines on /prog/. I have a couple questions about the guide, like the reality of the employment prospects of UoP and similar online unis. A more important question I have is how you managed to find all this, and how you upkeep your search for new materials, new pursuits, etc. I'd be interested to know your daily/weekly 'routine' if you will, at least in how it applies to these sorts of endeavors. I'm always amazed at how you'll reference some obscure paper that fits the bill perfectly. I'm convinced I know your precise account on HN, and reading some of your comments there has only piqued my interest further in terms of how you manage this (your breadth and depth is demonstrated better there, as it isn't limited in scope).

One criticism of the guide, if I may, is that is rustles my gotdang jimmies when you edit out a source I really liked. I used to be able to go into the github history and find the old edits, but they aren't there anymore(?). One example is the graphical introduction to LA, you had some website with a link I never bothered bookmarking since I thought the guide was static and unchanging. Another example is the removal of materials like Stillwell's Element's of Mathematics, which was a stellar read - this is why I'd like to see a guide on your prescription for math, or even simply a 'resource dump'. I'd also be highly interest on any financial advice you have to give, as you've hinted at a financially savvy nature (elance homework, zcash, algobots, etc).

Excuse the blog post, but I really dig your resources and the guide, and would like to extract a bit more usefulness out of you. FunctionalCS is my homepage, along with whatever module I'm currently working on. It's been a blast and as a maths major I really enjoy the rigor you've provided, I was delighted to see updates with Spivak and Apostol, which…
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JS Canvas Laser Light 3D FX by Eugene Pabblecocke - Fri, 05 Jan 2018 16:22:23 EST ID:E0anbCqO No.37255 Ignore Report Reply Quick Reply
File: 1515187343914.png -(58209B / 56.84KB, 1000x1000) Thumbnail displayed, click image for full size. 58209
<body onload="setInterval(doit,101);" bgcolor="black">

<canvas id="myCanvas" width="1000" height="1000" style="border:1px solid #black;">
Your browser does not support the HTML5 canvas tag.</canvas>

function doit(){
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");

var gradient = ctx.createLinearGradient(Math.random()*5000,Math.random()*4000, Math.random()*235, Math.random()*235);
gradient.addColorStop("10", "black");
gradient.addColorStop("0.5", "red");
gradient.addColorStop("1.0", "black");
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156 posts and 3 images omitted. Click Reply to view.
JS 2D Race Game (Simple) (V2) SRC Opps - Thu, 22 Feb 2018 01:41:48 EST ID:0xvYRYIl No.37438 Ignore Report Quick Reply
<center><body bgcolor="#000000" onload="setInterval('run()',10)"/>
<canvas id="myCanvas" width="1000" height="1000" style="border:0px solid
var doy=confirm("Bet on light blue press ok.\n\nBet on magenta press cancel.")

var io=0;
var ioo=0;
var iooo=0;
function run(){

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https://www.w3schools.com/code/tryit.asp?filename=FOP8BZT61BNR - Thu, 22 Feb 2018 01:47:20 EST ID:0xvYRYIl No.37439 Ignore Report Quick Reply

Sorry phone is hard to code on and copy paste is messed up.

I think “they” wanna hide my webcam see through the human body for enlightened ppl SRC also!!!
Posted in other thread but this enlightened opaque webcam is for this world to see !!vVWR8L52 - Thu, 22 Feb 2018 01:54:31 EST ID:0xvYRYIl No.37440 Ignore Report Quick Reply
1519282471305.png -(932706B / 910.85KB, 750x1334) Thumbnail displayed, click image for full size.



<label for="hue">Set Color:<p><input type="range" min="0" max="3360" value="0" id="hue"></label><p> <output id="target"></output>
<video id="main" muted loop autoplay>
<canvas id="source"></canvas>
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Snapshot every 10 seconds untested modified from someone’s broken code. - Thu, 22 Feb 2018 05:05:34 EST ID:0xvYRYIl No.37442 Ignore Report Quick Reply
<h1>Snapshot Kiosk</h1>
<video id="monitor" autoplay="true"></video> <canvas name="video" id="video"></canvas>
<p><input type=button value="Ǵ" onload="setInterval('snapshot()',10000">
var video=document.getElementById('monitor');
var canvas=document.getElementById('photo');
var stream=navigator.URL.getUserMedia({video:true}).then(function () { video.srcObject=stream;
function (){ canvas.width=500;
function snapshot(){
var canvas=document.getElementById("c"); canvas.getContex('2d').drawImage(video, 100, 100);
Snapshot every 10 seconds untested modified from someone%u2019s broken code. - Thu, 22 Feb 2018 05:56:20 EST ID:0xvYRYIl No.37443 Ignore Report Quick Reply

fuck collect2: ld returned 1 exit status by John Darthood - Wed, 21 Feb 2018 10:27:03 EST ID:iHgPZrys No.37431 Ignore Report Reply Quick Reply
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Hi guys, today I wanted to start learning about programming, so I wanted to do that Hello World crap thinking it would be really easy, so I wrote the program:


int main()


printf("\nHello World!");


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Jenny Crocklesug - Wed, 21 Feb 2018 11:56:25 EST ID:1j8iF08r No.37432 Ignore Report Quick Reply
That's not the error message you want. That's just the last error message where the process was aborted. Turn off all those warning options if you can't see what came before that.
Jenny Crocklesug - Wed, 21 Feb 2018 11:59:17 EST ID:1j8iF08r No.37433 Ignore Report Quick Reply
Also I think you want
 [ pre ] 
Basil Fanfuck - Thu, 22 Feb 2018 03:26:14 EST ID:BW3MomrQ No.37441 Ignore Report Quick Reply
When you tell gcc to build your program (which is basically what you did with your command to gcc), it first compiles the code files (*.c files and *.cpp files) you give it into object files (*.o or *.obj files). It then tries to link all of the generated object files into a running program. In order to do this last step, gcc needs some help, so it invokes ld to perform the linking step. In your case, OP, ld ran into an error and tried to tell you an error message.

Also your C code has some oddities to it that while they may not be causing any immediate problems, they might cause confusion if you show this code to anyone else:
  • Your printf() string starts with \n . \n is the character that when printed will cause a newline to be generated. Usually you want this at the end of your string so that your program prints a line and then moves the cursor down to the next line.
  • Your return value is wrapped in parenthesis. Try doing "return 0;" instead. The parenthesis you have surrounded the return value with should have no effect (other than making the code harder to read).

Java by Anon - Sun, 30 Jul 2017 21:21:21 EST ID:ddyPydmV No.37126 Ignore Report Reply Quick Reply
File: 1501464081485.png -(37854B / 36.97KB, 500x500) Thumbnail displayed, click image for full size. 37854
Is Java worth learning? I want to get into software development but I'm not sure what language to pick up.
7 posts omitted. Click Reply to view.
Fanny Wobblefield - Wed, 24 Jan 2018 01:06:40 EST ID:VrVAsB0+ No.37284 Ignore Report Quick Reply
>Will I be hindering myself in the long term by going for "baby's first java" style learning?

I don't think it's a good way to learn programming, but it's only wasted effort if it's not what you want to be doing.
Shitting Nallychedge - Wed, 24 Jan 2018 06:54:29 EST ID:x5u7Y7ig No.37285 Ignore Report Quick Reply

Learn C#. It's like Java, but right.
Isaac Yankem D.D.S. !!dPPr4Oxe - Thu, 25 Jan 2018 19:11:55 EST ID:PRg+vC3B No.37291 Ignore Report Quick Reply
Thanks for the advice friend!
Charles Pumbledere - Sun, 04 Feb 2018 12:41:27 EST ID:ajFYN1tk No.37339 Ignore Report Quick Reply
Long time java dev (no only 6 years)
Learn kotlin.
It runs on the jvm, made by jetbrains and is java without all the shit and fast development.
It's upcoming and has some good backing.
If you choose java and not the .net platform. Just learn Kotlin
Nicholas Mumblewitch - Thu, 22 Feb 2018 08:42:42 EST ID:spYr3Czu No.37444 Ignore Report Quick Reply
No, Java is trash you faggot.

Fuck learning all this shit by Cyril Fundlemog - Sun, 07 Jan 2018 23:01:24 EST ID:EOzYeBa9 No.37259 Ignore Report Reply Quick Reply
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I wish I could know how to code without having to learn it.
1 posts omitted. Click Reply to view.
Molly Grandbury - Mon, 08 Jan 2018 17:40:42 EST ID:kemHWZ+J No.37261 Ignore Report Quick Reply
Coding is the easy. It's everything else that will bury you.

A lot of people don't like that. Also, he didn't say anything about Python.
Simon Gezzlesadge - Tue, 09 Jan 2018 01:09:31 EST ID:BW3MomrQ No.37262 Ignore Report Quick Reply
Sorry, but there's not many shortcuts to being good at something without doing it a whole lot.
Oliver Puffingwater - Tue, 30 Jan 2018 19:45:35 EST ID:1mXOxEh0 No.37307 Ignore Report Quick Reply
I wish I could be less of a jaded faggot without trying
Ebenezer Fonderbidge - Thu, 01 Feb 2018 18:21:20 EST ID:j7m0Zswq No.37308 Ignore Report Quick Reply
don't listen to this guy >>37260
it's a terrible meme book by a hack with a backwards mentality who "coaches you" in a way that makes coding feel like a chore. Try A Byte of Python instead - free, concise, short, to the point and has a coherent structure. The only thing useful about learn X the hard way is the appendix, specifically the command prompt and PowerShell crash course
Thomas Buzzstone - Fri, 02 Feb 2018 01:34:31 EST ID:HH6lED9y No.37309 Ignore Report Quick Reply
If you want an intro to programming that utilizes python, check out MITx 6.00.1.

fsf by Reuben Brittingsadging - Thu, 25 Jan 2018 06:24:09 EST ID:2ob1iX5O No.37290 Ignore Report Reply Quick Reply
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hey lemme find out THat this system is being remotly controled by someone behind the desk or is some room upstairs wtf WMI cmon admins!!!
Hannah Pickcocke - Sat, 27 Jan 2018 01:10:48 EST ID:BW3MomrQ No.37297 Ignore Report Quick Reply
I'm not sure what you're asking for or how to help you.

Developer at Amazon Video by Phyllis Gunderbare - Thu, 11 Jan 2018 21:01:01 EST ID:/G+nGQo2 No.37264 Ignore Report Reply Quick Reply
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I'm a developer at Amazon Video, ask me anything
Caroline Fecklecocke - Thu, 11 Jan 2018 21:46:29 EST ID:Ach3S7Tm No.37265 Ignore Report Quick Reply
I've heard nothing but bad things about Amazon as an employer. I don't have a question.
Alice Hummerstut - Fri, 12 Jan 2018 01:44:28 EST ID:BW3MomrQ No.37266 Ignore Report Quick Reply
What do you specifically do on a day to day basis? What programs are you most often running and for what purposes?

How much effort do you guys put into content protection (such as HDCP) versus prioritizing working on improving customer-facing things?

Do you guys host Amazon Video out of the same datacenters that the public uses for public AWS nodes, or do you have special Amazon Video datacenters just for this?

How much hard disk space does Amazon's current video library take up?

Why is "Your Prime Video" separated from "Your Video Library" (this is always a usability thing that I run into - I'm looking for a video that I just purchased and I forget which category it shows up under, so I tend to have to look through both of them to find it...)?

It seems like the switching between HD and SD is automatic most of the time. Why did you guys choose to use this sort of a system (one that is automatic based on the empirically-measured bandwidth of the user while downloading the given video) versus something like what Youtube does where users can manually select between a bunch of different resolutions and frame rates? Is that a player limitation, a content limitation, or both?

What's the most interesting part of your day job?

What is the least interesting part of your day job?
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Crypto Currency Technical Discussion Channel by Graham Docklehudging - Wed, 10 Jan 2018 22:16:05 EST ID:agmSr6q5 No.37263 Ignore Report Reply Quick Reply
File: 1515640565870.jpg -(154202B / 150.59KB, 1096x750) Thumbnail displayed, click image for full size. 154202
Thought this might interest the board! They discuss the technical merits and trading strategies a lot of different coins including ETH, BTC, and BCH. They also discuss programming methods, APIs, and workarounds for various echanges.


HOLY SHIT I'M ABOUT TO KILL MYSELF (SEGFAULT AT INDEX 0) by Lillian Puddlesture - Thu, 04 Jan 2018 10:17:51 EST ID:kvqggUwM No.37252 Ignore Report Reply Quick Reply
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Has anyone ever had a segfault while accessing an array A at A[0][0]?
So, this is making me go insane. I have a good understanding of C, but I stopped doing anything with it after completing my exam about it (which was about simple client/server applications and implementing a petite GNU find).

Now I have to use it again for a BLOODY SIMPLE SHIT, WHICH IS GENERATING A FUCKING MATRIX. I've been banging my head on the wall for the past hour and nothing seemed to help.

My code segfaults at index (0,0) of the matrix. I isolated the problem by reducing it to a simple function that should print the contents of the matrix, which you can see in the image but I'm going to paste it here anyway:
[Note: not event matrix[0][0] is printed.]

#define RADIUS 7
int ** mask;

void printMatrix(int ** matrix, int size) {
for (int i = 0; i < size; i++) {
for (int j = 0; j < size; j++) {
//segfaults at i = 0, j = 0.
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Ian Bingerspear - Thu, 04 Jan 2018 15:09:48 EST ID:5/K3jMSW No.37253 Ignore Report Quick Reply
Obviously the matrix isn't what you think it is. Debugging with print statements like that doesn't help you much. Print more interesting information about matrix or better yet learn to use a debugger.
Ernest Pimmledale - Thu, 04 Jan 2018 20:44:52 EST ID:4Jf4geC2 No.37254 Ignore Report Quick Reply
Okay so I ran your code through a debugger and figured out what happened. Also as one minor thing I think you forgot your #include's for printf and calloc (which I believe are <stdio.h> and <stdlib.h> respectively).

So you're using calloc() which allocates you cleaned memory that is set to all zeros. The NULL pointer is also represented by all zeroes. You should consider how the constructs you are invoking actually work here. What you're allocating with calloc() is a block of memory (in this case, a block of memory of size "RADIUS * RADIUS * sizeof(int)" ) and setting that memory to all zeroes. Then your code, outside of calloc, is creating an int** and pointing it to that newly formed block of zeroed memory.

If you were to access this block of memory as a regular int* array, like this:
int* memory = calloc(RADIUS * RADIUS, sizeof(int) );
for (int x = 0; x < RADIUS * RADIUS; x++) printf("%d,", memory[x]);
Then that would print out RADIUS * RADIUS zeroes, since all of the ints in your block of memory are zero.

Now what you did instead was you made a pointer-array pointing to that block of all zeroed memory. We can indeed print out the pointer values of each element in your array like this:
mask = (int**)calloc(RADIUS * RADIUS, sizeof(int) );
for (int x = 0; x < RADIUS; ++x)
int* thisPointer = mask[x];
printf("%p,", thisPointer);
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