Updates for gendaylit and evalglare

Dear RADIANCE users,


we are happy to announce an updated version (from now on we have version
numbers, this release is called 2.0) of gendaylit. It is already
integrated in the Radiance CVS system, which means you can download it
with the HEAD-release. You can find it also on our web-site here (
http://www.ise.fraunhofer.de/radiance ) in a zip file, together with a

Version 2.0 has the following additional features:

if any of the Perez parameters are out of the model parameters, the
parameters are set to the border and an output is produced (+ a warning
If gendaylit is used with weather files, the specified instantaneous
points of time may be incorrect.This error occurs due to the fact that
measurement results are frequently defined for time intervals, not for
specific points of time.Although gendaylit is working correctly, this may
lead to wrong outputs especially at low sun altitudes. The "-l min_angle"
option avoids these errors by returning zero values if the sun altitude is
below min_angle degrees over the horizon. The default value is zero; the
recommended number for min_angle in the case of using weather files is 1
As the new gendaylit version does not depend any more on additional files
(except the further processing of the gendaylit outputon perezlum.cal, of
course), it is more stable than the version before.
Warning messages that are written to stdout, especially at too low sun
altitudes or at too high or too low sky brightness or clearness, can be
suppressed by the -w option.
The -v option disappeared.
The output during the night has changed: the error message is replaced by
zero numbers for the Perez coefficients.
The sun coordinates are also calculated when the sun is below the horizon.

The man page has been updated.

This updated version has been validated on a measured annual weather data
set - all possible radiation/illuminance inputs have been successfully
proven and show high accordance to the measured values.

Please give feedback to wendelin.sprenger@ise.fraunhofer.de if something
not working properly.


there is also a new version available on the ISE server (
http://www.ise.fraunhofer.de/radiance ).
There are some performance improvements included + some small bugs
The current version is now v1.11.

Jan + Wendelin