LB Incident Radiation — "invalid literal for float(): -nan(ind)"

grasshopper ladybug
, ,
1

Hi,

I’m getting the following error when running LB Incident Radiation:

Solution exception: invalid literal for float(): -nan(ind)

My setup:

  • Rhino units: millimeters

  • Geometry: Flat planar srf.

What I have tried:

  • Flipping the surfaces with the Flip component

  • Disconnecting and reconnecting all inputs one by one

  • Adding a grid size slider

The component turns red and results output shows Null. No other errors present except a warning on _grid_size before I connected the slider.

Here is the GH file with Internalised data: Solar radiation based facade panels_troubleshooting.gh (42.9 KB)

image
image1722×773 113 KB

Path for weatherfile: DNK_Copenhagen.061800_IWEC.epw

current versions of software:

Rhino: Version 8 SR30 (8.30.26103.11001, 2026-04-13) (I run on an evaluation license)

Grasshopper: 1.0.0008

Ladybug: 1.10.6

Radiance: RADIANCE 5.4 2023-11-05 LBNL (5.4.4ee32974b1)

Could you please help me understand the cause of this error and its solution.

Thanks

2

Hi @Romer and welcome to the forum.

I upgraded your account from new user to basic user. Can you try again? Remember to internalize the geometry in the Grasshopper file.

3

Thx Mikkel!

Here is the GH file. I added the Weather file as a URL link and internalized the Brep.

Solar radiation based facade panels_troubleshooting.gh (42.9 KB)

Thank you guys. Hoping you can help me figure out this problem.

4

Hi @Romer,

The issue is the input in the cumulative sky matrix. You need the direct/diffuse radiation, not illuminance. See the image.

image
image792×603 48.1 KB

5

Aaaah Wow. Thx Mikkel. You are a savior!