algorithmic modeling for Rhino

Hey all,

I thought this a simple problem with a simple solution, but I haven't had any success thus far.

I'm using the [Read Me] component to read a CSV file, which contains a series of decimal numbers. I'm struggling with converting the CSV data (read as strings) to floats. I've tried using [float(i) for i in x], but this calls the tree branch (i.e. {0;0;0}, etc.) as opposed to the string item. Image attached.

Anyone have the know-how?



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Where ever grasshopper requires numbers instead if text it will convert them. But you can force the issue by using a Number Param component before going into you python component. Or do you what to do this purely in python

Just an addition to Danny's great answer:

When dealing with python list comprehensions, you do not have to define an empty list first. Just write:

a = [float(i) for i in x]

Neither are working. I tried to "force" the output with a [Number] component initially (since that typically works) with no success. I also tried your suggestion, but I get the following runtime error:

Runtime error (ValueErrorException): invalid literal for float(): n/a

line 1, in script

Hopefully the image clarifies.


Du you get all but a few of the numbers converted?

Could you provide the whole input list?

Do you have any exotic locale set? (though GH seems to eat decimal commas as well as points)


Check Naruto's reply. Seems like you are trying to iterate through "x" list, but you haven't set it up as a list, in the first place.

It's either that, or you have some invalid value in your input (like <null>).
Please attach your .gh file in the future.

You need to select a list


I solved the issue, thanks to djordje pointing out the obvious. I already tried all of the standard and suggested solutions (hinted input 'x' as List Access, etc.), but I had a few invalid items in the CSV.

Thanks for the help. I appreciate all your responses.



P.S. djordje: I like to make the alterations personally (helps me learn/understand what I'm doing), which is why I withhold my definitions unless requested. Although I totally understand the need for one to dig into the file. I will post all necessary files with my next discussion. Thanks.






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