Computer Science Lounge - [Too Many Idea Men Edition]

[chiefshane]

Computing PI Competition

Here is the plan. I have wrote a multi threaded way of computing pi and I want to use it as a way to test our CPU's. Follow this link to get the code. After you have compiled it and installed the required software time how long it takes for you to compute after entering the command ./findPI 10000000 10000000. @Aremis

[chiefshane]

Would anybody know anything about pi clusters? I am interested in the algorithm they use to communicate. Is it done through a network interface? Is there like a main controller PI that then calls the other PIs to do computations?

[Eden]

No idea myself.

On another node. Anyone know of a good resources for looking up C libraries and similar for "to do this thing" > results in a list of libraries to use

[catsay]

Github/Stackoverflow is your closest bet. There's no alternative to reading lib feature lists really unless someone programs something like that.

[chiefshane]

for standard C libraries probably or the man page on any Unix like system.

The C Programming Language

[chiefshane]

Skills

In an attempt to organize people on this forum I have created this thread. This thread has a strict convention for listing different users and the skills they have so that for example you want to find sombody that knows Node.js you could come on here and search people with that skill listed. The same for people looking for others to do projects. Here is an example of the convention down below. Do not post anything on this thread unless you are posting your skills that follow this convention. Also note that I dont want different spellings for the same thing for example NODE.js vs Node.js. When you post follow the previous convention for listing that stuff and languages are not the same as skills. Finnaly put a rating by your skills with 5 being expert and 1 being novice. @wendell @Eden @Aremis Skills: Discrete math 2.5 Web Development 3 Languages: Python, Java, C, C++

[Eden]

Yeah i was thinking more of a good lookup place when you dont know the library you need. I didn't know what gmp did/or existed until i needed to install the library for your program to compile.

I supose google does a decent job with C + "thing you need"

[Eden]

Why note make it fancy

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Though its incredibly difficult to edit lol

[chiefshane]

difficult to edit lol

thats the problem lol

[chiefshane]

@Eden
You should share your project if you are writing some c code. I would be interested to see.

[chiefshane]

The Search for A community Project

[Eden]

I'm a complete newbie at C atm. I'd quite like to get a reasonable proficiency at C enough to write and read without issue.
I'm also interested in rust but I'm leaving that at the moment.

I have a couple of ideas for some Linux based programs that i need to properly flesh out into formed ideas.

[anadon]

Interesting topic, but I'm already fully committed on what time I have.

[chiefshane]

Multithreading in Java/Android Studios

Hi guys I am stuck on something and I was wondering if any of you would have any ideas. I wrote a networking API for my own server for an app. It runs asynchronously so I was trying to make a separate thread call it and wait while the man thread waits on that thread. I know how to do what I want to without multi threading but I am curious as to if I could make this work. This code starts everything b.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String password = ((EditText) findViewById(R.id.password)).getText().toString(); String email = ((EditText) findViewById(R.id.email)).getText().toString(); CustomerBuilder builder = new CustomerBuilder(); builder.addEmail(email); builder.addPassword(password); State state = new State(); state.setState(false); Object lock = new Object(); ShaneConnectCustomerLoginAdapter adapter = new ShaneConnectCustomerLoginAdapter(getShaneConnect(),lock,state); adapter.checkCredentials(builder.getCustomer()); synchronized (state){ while(!state.getState()){ try { state.wait(); } catch (InterruptedException e) { e.printStackTrace(); } } Intent myIntent = new Intent(CustomerLoginActivity.this, Employee_MainScreen.class); /** Class name here */ CustomerLoginActivity.this.startActivity(myIntent); } } }); public void checkCredentials(final Customer customer){ new Thread(new Runnable() { @Override public void run() { credentials(customer); } }).run(); } This is what makes the REST API cal…

[MFZuul]

Is it done through a network interface?

yes iirc, think you can do it wired and wireless

main controller PI that then calls the other PIs to do computations?

I think you can do that, iirc you can also set it up to have your desktop or what have you be the master

Videos

^this video touch's on the topic of distributing work (briefly this first video in the series is about hardware)^

Hadoop on a 100 Board Raspberry Pi Cluster

3 Node Raspberry Pi Cluster

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this is the extent of my knowledge

[chiefshane]

I was doing some discrete math hw and it went over some applied graph theory and it explained you could view processors as a graph problem. I wonder if you could create a cluster without a center or a main pi.

[MFZuul]

I wonder if you could create a cluster without a center or a main pi.

the second video in that list says thats what he is doing (if I am hearing him right, timestamped)

[chiefshane]

I definitely need to play with some of these at some point. I want to specialize in parallel computing.

[MFZuul]

you seen these?

https://www.parallella.org/board/