Figure 3: Example results of the weather category detection algorithm based on patterns for 6 subsequent days from 24.08.2005 to 30.08.2005 in Lindenberg. Clear sky irradiance (dotted grey) and the clearness index (grey line on top) in comparison to the measured global irradiance (blue line, bottom). Visualization is done with one-minute values whereas the detection is based on hourly averaged values.