About.com C / C++ / C#

Covering Open Source

Fri, 06 Nov 2009 03:40:34 +0000

As you've probably guessed, I'm a keen advocate of open source, albeit an equally keen user of closed source software, especially development tools. Having worked in a software house that sold software to banks, Closed software development is focused on providing something that the customer will buy. If they aren't focused then they're out of business sooner or later, whereas open source has the luxury of not needing to be commercial to survive. My point is that the world is big enough for both.

But it's also obvious that with 70 million + websites/blogs out there, there is almost certainly a lot of useful open source that is never heard about. So if you are working on an open source project (C, C++ and C# only) and would like a mention write to me at cplus.guide@about.com and tell me about your project, team etc.

Covering Open Source originally appeared on About.com C / C++ / C# on Friday, November 6th, 2009 at 03:40:34.

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Challenge 28 Marked

Thu, 05 Nov 2009 18:46:05 +0000

Congrats to Pedro Graca who once again wins though the competition was out of sight this time. His C entry calculated the puzzle answer in about 3 seconds and though it didn't create a valid CSV file, it would be churlish not to cite him as the winner.

I've had the first entry for Challenge 29 from John Downey of Purdue University. Starting from this weekend, I'll try and mark these as they come in but no source code will be published until the challenge ends.

Link to Programming Challenge Twenty Eight Optimise Fuel Transport
Link to Programming Challenge Twenty Nine Manage the Hunters

Challenge 28 Marked originally appeared on About.com C / C++ / C# on Thursday, November 5th, 2009 at 18:46:05.

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Computer Vision and Face Recognition in C and C++

Tue, 03 Nov 2009 18:38:07 +0000

Living in the UK which I believe is home to the most CCTV cameras per head of population (about 1 for every 16 people in the UK) means I'm not terribly keen on advancing this type of technology but you can't really halt progress, just try to control it so it doesn't get abused. We must be close the point of having software that can track a person in a crowd moving across a city, if it hasn't already been done.

Face recognition is a hard problem to solve from scratch but it's now a mature enough technology that even cheap compact digital cameras can identify faces. Open Source is making inroads into this as well with two libraries. The LibFace open source library uses the OpenCV library for face recognition and has got a complete collection of functions that are essential for building a face recognition system.

Intel originally produced the OpenCV (Open Source Computer Vision) library, written mostly in C which is about computer vision and has over 400 different functions covering 28 areas of computer vision research, of which one aspect is face recognition. There's even an O'Reilly book about using OpenCV and writing applications in C, C++ and Python. There's also a good guide to getting started with OpenCV from Leeds University. Intel sells a library IPP which is integrated with OpenCV so that if you have IPP, some functions are much faster.

Link to C Code Library

Computer Vision and Face Recognition in C and C++ originally appeared on About.com C / C++ / C# on Tuesday, November 3rd, 2009 at 18:38:07.

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Revisiting Google C++ Standards

Mon, 02 Nov 2009 17:33:40 +0000

Google produces a lot of software in C++ so they have prescribed a set of standards for all C++ Google Software. There's a lot of wisdom in there and some interesting stuff. If you're an experienced developer with C++ then you can probably ignore it but if you're starting out it's not a bad set of rules to take on board. Here are a couple of interesting points:

Namespaces

Don't use Using as in using namespace std; This pollutes the namespace.
You can use anonymous namespaces.

Exceptions

Google don't like you to use exception handling. Thankfully there are some "exceptions" to this rule regarding Windows Software and existing code that uses exceptions.

If you have Python on your computer then there is a Google python script that will check your C++ code to see that it conforms with the style guide.

Link to Tools and Utilities Library

Revisiting Google C++ Standards originally appeared on About.com C / C++ / C# on Monday, November 2nd, 2009 at 17:33:40.

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SlickEdit 2009 Review Published

Sun, 01 Nov 2009 18:49:31 +0000

Though I spend most of my time in front of an IDE, there was a time years ago when I would have welcomed something like SlickEdit which I have just reviewed. Back then, the the initials PWB might bring back a few memories! It's not true that it was short for Programmer's Waste Bin.

Since then of course Visual Studio's IDE has become pretty good and there's Eclipse/Netbeans and a whole stack more. So it's a competitive environment to be trying to sell an IDE in. My conclusions are that SlickEdit 2009 is an excellent full featured IDE (with a Macro programming language more powerful than C) that is great for development where you use different programming languages or platforms. But judge for yourself...

Link to Review of SlickEdit 2009

SlickEdit 2009 Review Published originally appeared on About.com C / C++ / C# on Sunday, November 1st, 2009 at 18:49:31.

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Challenge 29 Published

Fri, 30 Oct 2009 10:37:05 +0000

This is a nice easy speed challenge. There are 10,000 treasure hunters located across the continental USA and likewise there are 250 treasures. You are given the latitude and longitude of both treasures and hunters and have to figure out which 10 treasures have the lowest average distance of hunters within 100 miles so you can assign them to search for the treasure. The challenge is only concerned with managing the hunters not the actual search.

If a hunter is more than 100 miles from a treasure don't count that hunter. So if the total distance of all 10 hunters from one treasure is 265 miles then the average distance of hunters from that treasure is 26.5 miles.

Link to Programming Challenge Twenty Eight Optimize Fuel Transport
Link to Programming Challenge Twenty Nine Manage the Hunters

Challenge 29 Published originally appeared on About.com C / C++ / C# on Friday, October 30th, 2009 at 10:37:05.

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Two Different Implementations of MySQL

Wed, 28 Oct 2009 18:29:41 +0000

Amazon and Calpont use MySQL in two different ways; that's the beauty of Open Source. Amazon has just started offering a new web service Amazon RDS (Relational Data Store) to compliment its Amazon SimpleDB service which is essentially a way of creating fast lookup tables. RDS provides MySQL 5.1. You pay for the size of an instance, storage, data transfer in and out and extra backup over the first 100%. If you prefer other databases, they are available through the Amazon EC2 service.

Calpont have used MySQL in their InfiniDB Community Edition. This is a free customized version of MySQL that is optimized for analytical use opf the kind used in Data Warehouses. It offers multi-threaded processing with no limits on CPU or core count on a single server, no limits on RAM, CPU, size of database, or concurrent users and is available as free download. Calpont make their money by offering a commercial version of this. Kudos to them for providing a free download without requiring registration.

Programming Challenge 28 deadline Approaches
Only a few days to get your puzzle solving code in.

Link to Programming Challenge Twenty Eight Optimize Fuel Transport

Two Different Implementations of MySQL originally appeared on About.com C / C++ / C# on Wednesday, October 28th, 2009 at 18:29:41.

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Pike - An open Source Interpreted Programming Language (In C)

Tue, 27 Oct 2009 18:42:10 +0000

There are many programming languages out there that you will have heard about. Pike on the other hand is a new one to me. Written in C, it's an interpreted, object-oriented programming language. It looks a bit like C and C++ and C#, but it is much easier to learn and use. It's object oriented, interpreted, very fast, includes garbage collection and is easy to extend.

Developed in Sweden, this is very much an ongoing development with over 200 lines of code added in the last week. This what pike looks like:

int main() { write("Hi there! What's your name?\n") ; string name = Stdio.stdin->gets() ; write("Nice to meet you, " + name + "!\n") ; return 0; }

What makes it different is that it's interpreted. You can type in a statement and have it execute (if meaningful) immediately. As well as the documentation on their site you can also find some examples of Pike in PLEAC (Programming Language Examples Alike Cookbook).

Link to C Code Library
Link to About Compilers and Interpreters article

Pike - An open Source Interpreted Programming Language (In C) originally appeared on About.com C / C++ / C# on Tuesday, October 27th, 2009 at 18:42:10.

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New Direct APIs in Windows 7

Mon, 26 Oct 2009 08:11:44 +0000

Direct2D and DirectWrite are two new APIs provided with Windows 7.

Direct2D is a hardware-accelerated, immediate-mode 2-D graphics API that provides high performance and high-quality rendering for 2-D geometry, bitmaps, and text. The Direct2D API is designed to interoperate with existing code that uses GDI, GDI+, or Direct3D. Direct2D uses hardware acceleration where possible and offers better rendering than GDI. Note, it's not a managed driver but a native API that works with C and C++.

DirectWrite is a new text renderer that is device independent, can can use ClearText text rendering and OpenType fonts. It is GDI compatible in layout and rendering so providing an migration path for older legacy code. I spent a number of years doing things with GDI, (though never GDI+), back in the late 90s. GDI is now obsolete but of course exists in a lot of code. Both APIs are provided as COM interfaces and the new look MSDN has quote a few examples of their use.

New Direct APIs in Windows 7 originally appeared on About.com C / C++ / C# on Monday, October 26th, 2009 at 08:11:44.

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Look what got Installed

Sun, 25 Oct 2009 06:07:07 +0000

I try to keep the various bits of software on my PC fresh with new releases and the most recent one was MSN Messenger. I use it very sparingly but I think developers, certainly the ones I know have an obsession or at least a desire to keep all software up-to-date.

The Messenger update displays a list of things it will install. All but Family Safety is ticked- presumably this means that I'm putting my family in danger right? It also installs Direct3D (for games I guess or media display) and SQL Server 3.1 CE. Adding to the DB2, MySQL and SQL Server 2005 developer I'm already running plus Sqlite! Any more I've missed out on?

SQL Server 3.1 CE is based on SQL Server 2005 though the newest version you can get is SQL Server 3.5 CE. This is free and intended for use in mobiles or within desktop applications and for single users not multi. Also, it runs as a dll not a service like the free Express edition. It's curious that the messenger update uses version 3.1 instead of the 3.5 version listed on Microsoft's site. Does anyone know why?

Link to Windows Tools and Utilities Library

Look what got Installed originally appeared on About.com C / C++ / C# on Sunday, October 25th, 2009 at 06:07:07.

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