Sunrise sunset times in c?

The sample code appears to work in VC++ 2010 with a few minor changes: Compile it as a C++ file and not C Remove the include.

The sample code appears to work in VC++ 2010 with a few minor changes: Compile it as a C++ file and not C. Remove the #include line. Add a #define _USE_MATH_DEFINES at the top of the file in order for M_PI to be defined.

Change the two %T in the strftime() calls to %X. Now that you have a working sample you can debug the working version and your version to see where the calculation begins to differ and narrow in on the issue. Either step through the program or make liberal use of temporary printf() calls much like the sample does.

If you want specific help you will have to post your code (either a link to the entire file or particular snippets you need help with).

I have already update the sample as you described on your steps. But when I run the code, it gives incorrect sunrise/sunset values. If you can run the sample, can you set the variables year=2011, month=8, day=15, latitude = 28, longitude = 41 and run the code?

The correct value pair for sunrise and sunset times must be 04:27, 20:13. But I get 11:13, 00:22. Can you share what you get when you run the code?

– Fer Aug 15 at 13:33 I get: Sunrise 08-15-2011 04:17:19 Sunset 08-15-2011 17:16:17. Be aware that the sample appears to take a West latitude and North longitude as positive. This means that you are trying to find the sunrise/set times for (41w, 28n) which is in the middle of the Atlantic Ocean.

The sample also computes the times in your local time and not the time at the specified destination. – uesp Aug 15 at 16:15 thank you for your help. Finally I get it working correctly.As you mentioned, I putted the wrong location information.

My actual coordinates should be -29East, +41North. When I enter these variables(with negative sign for east), the computation gives the correct result. Actually it gives aproximately 7/10 minutes difference from my referance times but it is not a problem.

That difference must be between sunrising start/finish difference. Thank you. – Fer 08-150 at 6:46.

This seems quite easy to implement: williams.best.vwh.net/sunrise_sunset_alg....

Pure C implementations are apparently scarce but if You are willing to port either from C++ or C# then there are a couple of options: C++ Sunrise/Sunset Calculations C# Get sunrise and sunset time based on latitude and longitude.

I run your C++ sample on first link but the project shows wrong results. Pls read my edit above. – Fer Aug 15 at 12:52.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.