Grasshopper Python_select item by index

There is three tasks that i wish to achieve in my python script, please guide me (6.9 KB)

#1 Replace integer by index in the list i had created
e.g. index 0 and -2 to 1

#2 Cull integer by index

#3 Shift the list by one unit

@piac Hey Mate, can u guide me on how to select, replace items in my script?

Hi @jia.yeap,

# example list
list1 = [20, 10, 5, 7.5, 12]

# replace item by index
list1[3] = 8  # [20, 10, 5, 8, 12]

# delete by index
del list1[2]  # [20, 10, 8, 12]

# shift list by 1:
list2 = list1[1:]  # [10, 8, 12]

# or delete the first
del list1[0]

But your ghpython input hints need to be set to “List Access” in order for this to work.

1 Like

Great input. This works if your list is if you set yr hint. The issue I am encountering is I had performed mathematical equations inside the script and I need to remove first value and last in ‘a’

Hi @jia.yeap,
You just need to add one list iteration to your script.
Check the attached file. (10.2 KB)