string format

Jvos

how come that my string formatting is not working in C4D.

exposure = lamp[c4d.REDSHIFT_LIGHT_PHYSICAL_EXPOSURE]

this works like it should and give's me the exposure

x = 'REDSHIFT_LIGHT_PHYSICAL_EXPOSURE'
exposure = lamp[c4d.'{}'.format(x)]

but this give's an invalid syntax.

I want to format because I need a dict comprehension where I get each attribute from a list. like this

attributes = ['REDSHIFT_LIGHT_PHYSICAL_INTENSITY', 'REDSHIFT_LIGHT_PHYSICAL_EXPOSURE']
lamps = doc.GetActiveObjects(0)
dict_variable = [{attr: lamp[c4d.'{}'.format(attr)] for attr in attributes} for lamp in lamps]

is there maybe like a C4D slack? got always question, but also quick answers for other people. a forum is sometimes a bit slow.
My thanks!

mikeudin

You trying to create name of the variable with formatting.
But format is only for strings.
Maybe 'eval()' can help you.

Jvos

@mikeudin seems to work. maybe because it needs to have c4d.REDSHIFT_LIGHT_PHYSICAL_EXPOSURE as an expression and not as a string.

thanks a lot man!

m_adam

Hi @Jvos,

First of all, (no worry at all) I would like to remind you to read How to Post Questions especially the part about categories.
Since your topic is related to Cinema 4D please next time create a topic within cinema 4d development. (I've moved it).

Regarding your issue, pretty much all parameters in Cinema 4D are stored in a BaseContainer.
A BaseContainer is a dictionary which links an ID (Int) to a Data.
When you are doing Object[Something] you access the value within this BaseContainer.

If you write in the console c4d.REDSHIFT_LIGHT_PHYSICAL_INTENSITY, it will print you the ID of this parameter.
Then to get the value of a parameter which is stored in the object's BaseContainer, you don't have to pass a string, but the ID, which is registered with a SYMBOL NAME because it's easier to remember than an arbitrary number (In some case there is no SYMBOL equivalent for an ID).

So as @mikeudin suggested the eval function is the right way to go, or you can directly store the ID in your list.

attributes = [c4d.REDSHIFT_LIGHT_PHYSICAL_INTENSITY, c4d.REDSHIFT_LIGHT_PHYSICAL_EXPOSURE]

Finally, there is no official C4D slack/discord or chat.
Cheers,
Maxime.