Can not generate a UWG epw file

grasshopper dragonfly
1

Hi,

I am trying to generate an EPW file with th DF Urban Weather generator.
In doing so I get the following error:

Runtime error (DivideByZeroException): Attempted to divide by zero.

Traceback:
line 86, in script
line 154, in average_shgc, “C:\Users\ebe.KNR\ladybug_tools\python\Lib\site-packages\dragonfly_uwg\properties\model.py”
line 35, in model_to_uwg, “C:\Users\ebe.KNR\ladybug_tools\python\Lib\site-packages\dragonfly_uwg\writer.py”
line 48, in run_uwg, “C:\Users\ebe.KNR\ladybug_tools\python\Lib\site-packages\dragonfly_uwg\run.py”

I do not understand why this is hapening. Below the json file:

GEUT_08.7z (164.3 KB)

2

What a coincidence! The same bug was just reported here yesterday and I merged a fix a couple of hours ago:

Thanks for reporting!

1 Like
3

Hi @chris,

I updated Ladybug and even added windows to the model. Now it generates an UWG.json but no EPW file. I tried to simplify the geometry but with no luck. Now I do not know what could be the issue here.
KRAP_19_3dmodel.gh (416.4 KB)
in.bat (398 Bytes) unnamed_uwg.json (3.9 KB)

4

I should be better at parsing the error log from the UWG. Here’s the error that you get when you run the in.bat file:

image
image964×56 2.13 KB

It looks like your model is somehow getting “5C” assigned as its climate zone. I’ll see if I can investigate further. But you can always change this to 5A in you .json file and then rerun the .bat file.

5

I just pushed a fix to the development version of the plugin, which should address this case:

You should be able to get it with the Versioner shortly. Thanks for reporting @Erikbeeren !

1 Like
6

Hi @chris,

Again having trouble with generating UWG epw files. Error message:

The Urban Weather Generator Failed to run.

image

Somehow the batch file does not run correctly. The UWG.json is created but urban epw not.

DF.7z (310.8 KB)

Update:

Funny when I save the file as a DFJson and import this to generate a uwg epw file everything wirks fine.

image
image1394×559 77.4 KB

Update:

I think I found the reason. When I defined the folder path the error occured.

image
image1306×205 22.4 KB

7

Thanks for reporting this, @Erikbeeren .

Hm. I think the original issue might actually have been related to the obstacle height that you have in your successful case there since I was able to get a math domain error in the wind profile calculation with your original uploaded file. I just pushed a fix that will catch the case of the failure of the UWG here:

You should be able to get it with the LB versioner in an hour or so if you still need it.

1 Like
8

Hi @chris

Sorry for bumping this 4 years old thread but I am also running into the same issue and not sure what seems to be the problem.

Would appreciate if you can assist in diagnosing the issue!

Error prompt below:

  1. Solution exception:The UWG failed to run:
    UWG model simulation failed.
    float division by zero
    Traceback (most recent call last):
    File “C:\Users\ANGA\ladybug_tools\python\lib\site-packages\uwg\cli\simulate.py”, line 50, in simulate_json_model
    uwg_model.simulate()
    File “C:\Users\ANGA\ladybug_tools\python\lib\site-packages\uwg\uwg.py”, line 1353, in simulate
    self.UCM, self.UBL, self.BEM = urbflux(
    File “C:\Users\ANGA\ladybug_tools\python\lib\site-packages\uwg\urbflux.py”, line 38, in urbflux
    BEM[j].building.BEMCalc(UCM, BEM[j], forc, parameter, simTime)
    File “C:\Users\ANGA\ladybug_tools\python\lib\site-packages\uwg\building.py”, line 457, in BEMCalc
    VolCool = self.sensCoolDemand /
    ZeroDivisionError: float division by zero

-LH