Hi All, After so many years I discovered an error in my program Zonwvlak.exe. Of couse there have been more minor errors, such as typing errors, but this one is a little more serious. But don't panic, as far as I know no one has noticed this error at all.
It happens with the calculation of lines for the sun's azimuth and altitude and only if the latitude is more then 66.56 or less then -66.56 degrees. I don't think many people will have calculated such lines for sundials at these latitudes. And not the whole line is wrong; only one of the points is wrong, namely if the sun's azimuth is + or - 180 degrees. And the error is only visible if the calculated point is a real point, that means the sun must be above the horizon and the sun must shine on the dial's face. This error is removed and I placed a new version for download in the package Zonwvlak.zip. In the mean time, with the help of Mac Oglesby, I discoverd that the windows interface for my programs also runs with windows 3.1. If you have windows 3.1 but not windows 95 you still can use this interface. Mac Oglesby uses windows 3.1 with his Macintosh computer. Happy dialling, Fer de Vries.
