Data reliability


Hi everyone,

I’m an Italian student at the University of Pisa. Due to the fact that I’m doing my thesis through Ladybug and Honeybee I had to verify Ladybug+Honeybee data reliability. Down here you will be able to check them. The analysis has been run for Pisa during May, September and January.

Reading the results I have extracted from the softwares I can say they are quite good. The data pattern is fine and the most difference can be found on the north exposition. This is because of the Italian Regulation Data that you will find inside takes the values through the Liu-Jordan model, considering different mode to build sky dome (isotropic). Indeed Ladybug or Honeybee use an anitropic sky model Perez-based.

Pleased to know your opinions,

Claudio Campanile

PS: I have internalized data and turned off the radiance tool toggle to not choke your pc as you open the file. (194 KB)

Algorithm / equation daylight factor and rendering engine

Thank you Claudio for sharing this with the community.

Great to know that Ladybug and Honeybee passed your validation process! :slight_smile:



Really awesome stuff, Claudio. I am putting up an image here that shows the comparison in case people don’t want to download the file and open it. The 6 values in each panel indicate the radiation on each of the faces of a cube. I am a bit unfamiliar with the Liu-Jordan model but I know that an isotrophic sky counts the diffuse radiation as uniform across the sky, meaning that it is not as accurate as a Perez-based sky. Can you confirm that is true?


Thank you Chris for taking a screenshot with data.

Going back to your question about Liu-Jordan, it is worse. Actually I’m pretty puzzled by results that should be higher instead of lower. I should go deeper finding the exact method they have used, because I can’t find it on the official data sheet. Sometimes they get values from a direct measurement through envoirmental-boxes spread on Italian territory.



Thank you Chris. I just pin it to the canvas so you would see it with no click…


it is so interesting