Ask MetaFilter questions tagged with computer and programming

Your script is my command!

Drasher — Tue, 22 Dec 2009 13:09:18 -0800

[Software Development filter] I am working on a project that uses a PC (Windows) and a dedicated microprocessor to perform a specific task. I want to create a scripting language that will allow the user to write their own sequences for the tool. The front-end of the software is being created using MS Visual Basic (Visual Studio) 2008. There is a "processing" back-end being created with the same development package, but using C++ to create a DLL. The DLL uses USB to communicate with a PIC (PIC24FJ256GB110) microprocessor that will control elements of the tool (heater, flow controllers, valves, solenoids, and relays) and gather data from other elements (pressure sensors, temperature sensors, liquid sensors, gas chromatograph).

I want the end user to have the ability to write a script and have the tool process the commands.
The script will have a simple language and limited number of commands.

For example:
10 DELAY XXX ms/sec/min
20 TURN ON PUMP_1
30 TURN OFF VALVE_3
40 FLOW_CONTROLLER PURGE
50 FLOW_CONTROLLER 100 ml/min
60 IF PRESSURE_SENSOR_1 > 100 THEN GOTO [line number]
and so on...

I have searched for and found a couple of "tiny basic" interpreters written in C that look like they could be modified and wedged into service. These interpreters use integers only, I might need floating point capability (pressure value comparisons, etc.) One interpreter requires line numbers the other uses labels for GOTOs and GOSUBs. I don't know if I should use line numbers (requires renumbering at some point) or labels (preprocess a symbol table).

I have a feeling that the end users are not very computer savvy so the scripting would have to be easy to understand and provide adequate error messages.

Do you (or someone you know) have an idea of a better path?
Should I try lex & yacc?
Should I just suck it up and try starting an interpreter from scratch?

Any and all replies are welcome.
AskMe has pulled me out from a jam before, PLEASE do it again!

Help me be an IT wizard.

Anonymous — Fri, 23 Oct 2009 06:36:15 -0800

I will need to change careers, but I have a bit of time to plan this out. What should my next computer- or education-related job be? About me, I’m American, living overseas in Tokyo. I have a wife and baby girl. I’m teaching English at a private high school/jr high, and enjoy the work very much. What I would like to do is move back to the U.S. and teach English at an American jr. high or high school. The catch is I don’t have a teaching certificate, and would need to take classes to get that. In addition, states are slashing budgets left and right, and even experienced teachers are being laid off and having a hard time finding work. If you have any advice in this area, please let me know.

So…the other arena I’d like to see about gaining skills/experience is computers and programming. If you ask me “what job?”, well, that’s kind of my question for you. What kinds of IT jobs are out there? What can I do all by myself with my iMac at home to gain skills and even make money (I’m thinking Web-based work, perhaps). I don’t know programming languages, but I’m fairly autodidactic given half a chance, and think I could teach myself; again, I have at least a year, probably more like 3 or 4 years before I make the switch. I am fairly computer savvy, though when it comes to typing code I guess I hit a wall.

My second question, then: what are some wise ways to spend the next couple of years teaching myself IT / Web / Programming skills? How to build up a portfolio of sorts during that time as well?

Make me more geeky!

stevyb — Sat, 03 Oct 2009 10:56:05 -0800

How can I (non-programmer), create a customized installer? (see details please!) I have an application that I have to install on alot of workstations, but it requires to install some MS Office service packs before the ACTUAL .exe file is installed. AND THEN , we still need to copy some data files into different directories. Only after the 20 step installation READ ME is followed to the tee, does the application launch and work correctly. Sorry, I don't know what language it was written in and I don't have any programming experience. I was hoping to make one EXE that does all of the steps automatically in a wizard type format. Sorry for the long explanation!

How to get an intro to computer sciences?

Mis-Information — Tue, 25 Aug 2009 11:14:12 -0800

Should I go back to school and take some computer programming classes? I've got my MLIS and work in Archives now, I'm sorta interested in Content Management but I have no useable computer knowledge. Would an introductory course help me see where my strenghts are and what I might possibly be good at? I'm not sure where to go from just having my Master's on top of the fact that I'm not sure I want to stay in the Archives field. I'm more interested in Records Management but I know I lack a lot of the tech experience

Specifying software speed specifically

crapmatic — Wed, 10 Jun 2009 10:34:00 -0800

When designing a programming project, what is the usual method for imposing speed requirements, such as "function X must accomplish so-and-so in 2 seconds or less"? The problem here of course is that all computers run programs at a different speeds.

Help me program my AI to win a competition!

theiconoclast31 — Sun, 03 May 2009 15:04:54 -0800

Teach me how to program a robot for my upcoming programming competition! I'm looking for tips, tricks, and sources of inspiration to help write an awesome AI. Some details:

I have two days to write the AI. The robot moves and races, and does other things. It's a 1v1 competition. I'm being purposely vague so this doesn't cross the line and become HomeworkFilter. Please tell me if you want more details. I'd really like to read stuff like Iocaine Powder Explained.

Machine, point me to food

klangklangston — Mon, 16 Mar 2009 17:45:20 -0800

Where's my food? How to make a web ap that tells me how to find vegetarian food easily? Ok, so, first off—I'm not tremendously programming savvy, so don't be afraid to talk down to me in simple terms (seriously, don't assume I know anything).

Here is what I want: I want to be able to go to a page (either on a computer or a phone) and see where the nearest vegetarian food is (vegetarian restaurant or just a place that has veggie food). I would like to make this open, so that I don't have to find every vegetarian dish everywhere (crowdsource).

I assume that what I need will be some sort of database that accepts submissions easily, and that will work with google maps; and some server space to run it from.

Given that—if I want to build something that does this, what do I need and what do I need to know? Is this something that can be built by a programming novice (I haven't done any programming since high school and that was still mostly basic. I have a moderate grasp of HTML, but little CSS)? How hard will this be? What should I know when I start to build it?

Need to decide which computer skills I need

cherie72 — Thu, 05 Mar 2009 08:28:49 -0800

What computer skills should I acquire to be relevant today? Dreamweaver? HTML? Flash? I don't even know what the options are! I'm not old (30something), but I didn't grow up with computers. I taught myself Basic from a book as a kid, tested out of that class in high school, and never took another class like that again. I learned MS Office on the job and have always had admin jobs that didn't require any programming or more involved computer skills.

In order to be relevant, it seems employers want more knowledge than I have to offer. Everyone wants either design program experience (I'm not a designer, but nowadays they expect an office coordinator to get involved, it seems) like Adobe Creative Suite, or web-related experience.

My question: if I want to work in marketing, small-business sales, etc., should I take a class in web design? Which programs should I know? Do I need to know HTML? (I don't even know basic HTML tags)

Every business has a web site, Facebook page, Twitter account...I can use those things, but I can't create them. Is taking a class the way to go? Or are there books you can recommend that are better? I'm actually quite comfortable with computers and a pretty quick study. But I won't lie about my skills and try to fake it as I learn on the job.

What do I teach my kids instead of line number BASIC?

majick — Sat, 21 Feb 2009 11:32:14 -0800

What's the modern day equivalent of old school "line number" BASIC as a tool for young children to play and learn with? As with many of us of a certain age, I spent a lot of time writing software in line number BASIC learning how to break problems down into component algorithms and generally getting a sense of how electronic computing works. The advantages of such a language as a learning tool are pretty well known: the constrained vocabulary and relatively powerful primitives make it fairly easy to learn, although obviously not the kind of thing you'd want to write production software with. I'd like to share at least a sliver of this experience with my own children, but the chances of getting them to sit down in front of a crumbling TRS-80 or Apple II in order to learn are slim.

So instead I'm looking at other options. Ideally I'd like a language and execution environment that is somewhat multiplatform, has graphics and sound support, uses a language I know or can learn relatively easily in order to teach, and most ideally is procedural rather than OO. A few I am considering are:

LÖVE - a Lua system for creating games. Lua looks fairly approachable although I don't know enough of it to teach, and I'm not entirely sure about making young children wrap their brains around the idea of callbacks in order to get anything done.

Pygame - a framework for Python game creation. I only speak a little Python but it's learnable, I suppose, and the presence of an "immediate mode" interpreter is compelling in terms of being able to learn the basics interactively. However, I'm not at all convinced I want my kids using an OO language before they understand procedural programming. That seems like putting the cart way out in front of the horse in terms of depth of learning.

Squeak - a Smalltalk implementation. Yet another OO language, although at least a fairly pure one, and I can probably dust off my long-rusted Smalltalk skills to teach it. But honestly, who even knows or cares about Smalltalk any more?

Scratch seems like a Squeak-derived project of some kind, and the visual programming approach seems aimed at very young or only partially-literate learners. I'm not sure this is the kind of thing I'm interested in at all.

Processing has some of the attributes I'm looking for, but may not be an ideal learning language due to being extremely visual in emphasis, the OO, and the Java syntax.

Visual Basic is really BASIC in name only; it's not a language I want to teach, nor one I'd want my children to bother with, and it's tied utterly to a platform I don't particularly care about.

So, folks, I'm not seeing a very attractive range of tools. What am I missing? Aren't there tools for kids to just sit down, play with, and make things? Or is the entire concept of teaching fundamental computer literacy an obsolete one in the modern age of children surrounded by closed, sealed, consumer-oriented devices that are made by distant wizards?

Suggestions (books, projects, things to learn, things to do) for a 2nd year Computer Science Student over Winter Break?

Javed_Ahamed — Fri, 12 Dec 2008 16:05:06 -0800

Suggestions (books, projects, things to learn, things to do) for a 2nd year Computer Science Student over Winter Break? Winter Break is soon approaching and I feel like accomplishing something over it. I am a sophomore computer science student, and I was wondering what the hive mind might suggest to do with all this new time available! Any computer books, online lectures, sample projects (Im going to learn C# over break, maybe some open source projects that are friendly to noobs?) or whatever to help get an edge on the competition and have fun are welcome! Also included are any things you feel essential to learn, tech wise or not.

Right now I know C and Java, and a good level of python and use linux if that matters. I am taking functional programming languages and Algorithms next semester as well.

Ideally, my plan so far has just been to learn a new language or two, get experience coding in these languages (don't know what to code or how to find an open source project to really work on though) and get head start for next semester.

Whatever your thoughts/experiences please do tell! And happy holidays!

[Internship Filter] Help me find a programming internship (computer science student) over summer break!

Javed_Ahamed — Thu, 20 Nov 2008 17:37:02 -0800

[Internship Filter] Help me find a programming internship (computer science student) over summer break! Hey guys I am a 2nd year computer science student at the University of Maryland and I am just getting around to looking for a summer coding internship to help get some experience. The problem is I have no idea how to start looking/how to distinguish myself from the crowd. Not really sure what to put on my resume or what to do to prepare for interviews either. The problem is I have no real experience to begin with, which is why I am searching for a internship so I am not sure what to put on my resume... So far i just have little odd things here and there from high school, most of it not even related to programming.

The two or three interviews I have gotten, I have mostly been rejected due to "no prior experiences" or because I haven't taken junior and senior level classes like data structures or algorithms.

I know everyone says to "make something" so you stand out and while I experiment with new things almost constantly I can't seem to make the jump right now to just starting to make something as I do not know where to start.

In summary do you guys have any advice you can give me to help snag a programming summer internship, and to help stand out from the crowd? Thanks a bunch!

Learning to program help?

btkuhn — Thu, 02 Oct 2008 22:24:08 -0800

Help me advance my computer education! I have been teaching myself computer programming over the past few months by working through this online Python textbook, and trying to complete the exercises on MIT's opencourseware Intro to Computer Science.

The tutorial does an excellent job of explaining the fundamentals and I'm now familiar with basic syntax and structures. However, I'm kind of at a stopping point. I've basically read through the tutorial (and one or two others) twice and finished the exercises in it, but I haven't completely submitted to knowledge everything in it. Just as importantly, the exercises provided in the tutorial cover only the basics and I doubt that if I was faced with a "unique", complex problem that I'd be able to write my own code to solve it.

So I have two questions:

First, based on my past experience in mathematics, the best way to learn new material is to go through a set of exercises/problems, try to do them on my own, and then look at the solutions. The MIT site has exactly what I'm looking for but doesn't have solutions or suggested code, and I've already finished going through that site. Surprisingly, I'm having a lot of trouble finding other sources for these type problems. Can anyone suggest a good place to get exercises with solutions that would help me to learn and practice my skills? Perhaps other college's intro to computer science class websites that make their homework available online (preferably in Python)? Or, alternatively, any suggestions for other ways to reinforce the material?

Second, where to next? After I master the basics that are covered in the "Python for non programmers" tutorial, I'd like to continue to get better and learn how to do more complex things. It doesn't seem like learning another language is a great idea at this point; better to master Python rather than gaining a cursory understanding of several languages. How do I get better? (A side note-programming does not come naturally to me at all, so the advice that I've received from my two computer-nerd friends, "Just start messing around, do cool stuff" has not been helpful at all. I do much better with structured stuff like you would get in a academic course).

Thanks!

arrays of strings in C/C++

phllip.phillip — Sat, 27 Sep 2008 04:56:58 -0800

I am currently a second semester programming student and I missed class because of jail; I was trespassing. my problem is, in my structured programming class we are using C/C++ and I need to know how to make an array of strings: multiple strings stored in an array. can someone help or guide me in the right direction.

Live AIS data is a web browser

kaozity — Mon, 11 Aug 2008 10:55:58 -0800

Hi, Another oddball question... I have a live data stream of AIS data and I would like to take the data and ultimately display it on a world map through a web browser. The problem is that I have no clue as to how I would display live updated information on a map. I would like the map to update as the stream of data is coming in. This might be an ambitious project for someone who is weak on web programming, but i figured it would be worth looking into.

PHP: How do I get the explode() function to work with multiple separators in a row?

kaozity — Fri, 01 Aug 2008 08:25:00 -0800

PHP: How do I get the explode() function to work with multiple separators in a row? I am using the explode Function on a string where there are multiple spaces after a word because it is tabbed. When I use explode as follows

$peices = explode(" ",$theData);

the $peices array does not record any of the data that comes after the section with multiples spaces. Any idea on how to get a complete array?

Make Apache recognize Perl!

kaozity — Wed, 28 May 2008 05:49:15 -0800

How can I get my web server to interpret perl I am playing around with perl for the first time in my life. I am using a fedora core 8 machine. It seems to ave all the essentials installed already (apache, php, mySQL, and perl). However, I make a file called perl.pl and it does not seem to translate correctly. Here is what is in the file:

#!/usr/bin/perl

print "Content-type: text/html \n\n"; #HTTP HEADER

# DEFINE SOME SCALAR VARIABLES
$number = "5";
$exponent = "2 ** 8";
$string = "Hello, PERL!";
$stringpart_1 = "Hello, ";
$stringpart_2 = "PERL!";
$linebreak = "
"; #HTML LINEBREAK TAG

# PRINT THEM TO THE BROWSER
print $number;
print $linebreak;
print $exponent;
print $linebreak;
print $string.$linebreak;
print $stringpart_1.$stringpart_2;

When you go the the browser, you see the following
http://[ip address]/perl/perl.pl

As you can see, you prints out exactly what I type. Am I doing anything wrong? Am I suppose to enable a perl service or change a configuration file?

Learning Programming/Logic/Algorithms by Yourself (preferably practice programs to write)?

Javed_Ahamed — Thu, 24 Apr 2008 19:34:56 -0800

Im a Freshman Computer Engin. Major and I want to learn more programming/logic by myself. Any books/Resources/Sample Projects you might recommend? In class we have projects/homeworks we do (Im doing Java now btw) and that helps us learn how to actually program instead of reading a book and letting the syntax/logic pass over our head. However i feel like I want to learn some languages by myself and everytime i try to do this I always end up giving up or just not learning anything much useful in the end to actually program. So this is kind of a multi part question:

1. Are there any resources out there that give sample projects with answers or suggested solutions out there? I don't mind paying for anything.
2. Any resources to help build programming logic? Or theory? (Maybe things like Djkstras algorithm nicely explained comes to mind)
3. Also what languages might you recommend to learn myself? I want to learn something that is actually useful, and might help my resume. (not something like pascal :D). This also fits into what resources can help me learn these languages.

Thank you!
(btw this is my first MeFi question and Im not sure if its good enough. I am glad to be part of the Hive Mind at Last!)

when does a wise man quit?

WannaBeAPhD — Sun, 13 Apr 2008 18:59:44 -0800

Background: I am 41 years old. I am 16 credits shy of graduating with a BS in Mathemathics. my GPA is 2.79, I have over 250 hours of attempted coursework, 144 of that is being counted towards my degree. I program and design software systems for a living. The Problem: I really love math and computer science but I am lousy at learning. when I say lousy I mean slow. It is an all or nothing proposition for me I am either a master of the material or I do not know it. When I have to study I experience psychosomatic symptoms, irritability, out of body experience, confusion, trouble concentrating. This has been happening since I was a child, I have a real aversion to studying, and it has gotten worse now in my adult years. I was diagnosed with ADHD about 8 months ago. The metadate works somewhat well to clear up the fog but when I have to study hard nothing helps.

I can perform my job well but that usually does not require me to think of the formal methods or theory about my job unless I am really pushing what I want to get implemented. To do my job I have self educated over the years I have read a large number of books because of interest in the material and the need to do my job.

I get bored at work doing repetitive tasks or tasks that don't require me to innovate or do research. I've just about reached the point where I have to become a bureacrat. I want to be able to continue to innovate, research and learn and I really want to study and become a PhD. There are jobs out there that I would qualify for if only I had a little more education adn the title. If money were no object I would simply study and take as long as I needed to in educating myself. That luxury is not available to me.

Is it wise for me to continue dreaming this way or should I simply accept my limitations and give up hope. I do fear that giving up hope will severely shorten my life. When I think of it I can feel the emotion build up. What does a wise man do when faced with the reality that he may never be what he has always wanted to be?

Replication in MySQL 5.0

kaozity — Thu, 06 Mar 2008 10:16:12 -0800

Does anyone know of a quick and clear guide to set up my MySQL Replication in MySQL 5.0? Does anyone know of a quick and clear guide to set up my MySQL Replication? I want a master and multiple slaves. All machines are on the same LAN. Must be for MySQL 5.0. Of course, I want it to automatically replicate itself.

How to teach myself computer science?

petah — Sat, 12 Jan 2008 18:41:54 -0800

I want to teach myself computer science. I know that teaching myself is far from a university education on the subject, but I'd like to try. How can I teach myself? What are books/lectures/tools/websites/anything that I could use to do this? Covering everything from the programming languages themselves, to algorithms, software development, and the mathematics background necessary for this. Starting with freshman year from college, I always considered changing my major to Computer Science but I never acted on it, and now it's a bit too late for me. I took C classes when I was younger, but it was mainly as a hobby.

If you're self-taught in the field of computer science, I'd love to hear from you. If you're university trained, even better. I'm relatively self-motivated (I know it's not easy to teach yourself these concepts), and have 2 semesters of experience in Java. (I know, I know.) I want to learn it all.

Fed up with Microsoft (.NET)

jjsonp — Sun, 09 Dec 2007 11:36:46 -0800

Best programming language for internal automation? I don't have any formal programming training but have written and read enough that my code is fairly 'tight' - all object-oriented, all of my projects utilize code-reuse from the classes I've created, etc.

I write programs to automate tasks I perform as a DB admin. I have one intra-office app with an interface but all the others are just desktop apps (most without forms) for automation - a lot of data-access, file preparation & archival, data-logging, etc. We are on a Microsoft platform so most of my code is in VB6, some in VB.NET, some in VBScript, and some in SQL. I have flirted with JavaScript and C# and don't think I'd have much trouble switching.

Over the years I've grown increasingly frustrated at Microsoft's direction with regards to the security implementation in Vista, the ever-changing/expanding nature of .NET, etc. After a year of wanting to wipe Vista I finally did, putting 64-bit XP on my machine...what a relief! I've also seen the advantages of open source - its flexibility, availability, cross-platform nature, and constant innovation by other programmers and users.

Anyway, after re-installing everything, some of my compiled VB.NET programs no longer work! The particular project sparking this question was compiled and stable for over a year on 32-bit XP and Vista; it is suddenly broken (even after I checked to ensure it was compiled to run on x86 - a gotcha I'd already run into on 64-bit). I have had this happen before when the latest & greatest '.NET framework' or VisualStudio version was released, and frankly I'm sick of it.

After struggling for hours to track down the reason for my program suddenly being broken I just said "screw it" and started re-writing it in VBScript...though there are lots of disadvantages to a scripting language (especially error-handling and forms), the BIG advantage is that every VBScript program I've written during the past 7 years still works perfectly on the 8 or 10 flavors of Windows on my network. I never have to install special frameworks or DLLs (depending upon what object model I'm referencing) or anything else - it just works.

So my question is this: what would you recommend for non-web intranet programming of the sort I'm doing? Something that will work well on all flavors of Windows from 2000 Server to Vista 64, allow disk and network drive access (with the Windows Server security model), easy data access for SQL Server and Microsoft Access, etc.? A good IDE would be nice too, particularly when I'm learning the language - please throw in any IDE recommendations you have as well (Sharp?).

I'm guessing Java would be the way to go but I'm just wondering if there are other recommendations. Thanks!

computer programming

amsterdam63 — Mon, 15 Oct 2007 21:24:53 -0800

How do you program computer graphics? I know most operating systems are written in c or c++, but how do the graphics fit in? Do you somehow program them into c or what? And how does any program create an interface?

Laptop motherboards that can boot from USB

DrSkrud — Wed, 03 Oct 2007 15:22:20 -0800

Can you name any laptop motherboards (brands, models, etc.) capable of booting from a USB flash drive? We're working on a robotics project at my university, and we're thinking that using a small linux kernel on a flash drive and a laptop motherboard would be much more sustainable (and easier) than dealing with microcontrollers.

What we need to find is a motherboard that can boot off of a USB flash drive. I know these exist, but I have no idea how to find them!

Does anyone know of a way to create a line graph using html or javascript?

kaozity — Mon, 30 Jul 2007 06:43:57 -0800

Does anyone know of a way to create a line graph using html or javascript? I need to create a line graph with html or jave script without paying a company $99 for their javascript it (e.g. swiftchart). The graph needs to handle multiple trends in the same graph... meaning that I would like to see 3 or more lines going accross in one graph.

Any Help?

How do I get an automatically generated line graph from a text file with a list of numbers?

kaozity — Mon, 25 Jun 2007 08:44:44 -0800

Is there a program that can automatically create line graphs from a text file with a list of numbers? Is there a program that I can have running in the background of my windows machine that will take a text file with a list of numbers, formatted as follows...

121
324
53546
4343
2342
etc...

and produce a line graph in jpeg, jpg, bmp, or any other common picture format?