[SOLVED] Extending a Python List

Gyroman · 06-30-2016, 05:52 AM

p = 5
values = [150,320,120,550,630]

I want to add the index to the list of values;
values
[[150,0],[320,1],[120,2],[550,3],[630,4]]

Code sample which fails;

for i in range(p):
____values[i] = [values[i],i]

TypeError: 'str' object does not support item assignment

It used to work then stopped.. can't see any change I made to values list ?

pan64 · 06-30-2016, 07:36 AM

this works for me:

Code:

p = 5
values = [150,320,120,550,630]
valuesxx = {}

for i in range(p):
    valuesxx[i] = [values[i],i]

check the type of ___values

Gyroman · 06-30-2016, 07:18 PM

Thanks.. Yes type of 'values' had changed..

I have a couple of simple questions about Python 3.3

After
>>>import prog
returns
>>>

(1) How do I re-run prog without quit() and re-import..?

(2) Inside prog what command do I use to exit on a condition before prog ends normally..?

pan64 · 07-01-2016, 12:14 AM

1) usually you have a function and you only need to invoke it again. (but I have no idea about your environment at all)
2) I do not understand

Gyroman · 07-01-2016, 02:13 AM

Linux on HP Laptop.. Python 3.3

(1) I create a module in gedit and import to run. I want to know if there is a command I can use to re-run the same module without having to quit() and restart Python and re-import it again to run it a second time.

(2) Just mean how to exit a Python module based on a condition.. ie prematurely..

thanks

pan64 · 07-01-2016, 03:26 AM

1. reimport is quite simple, just type import module again. But it won't rerun anything else just the initialisation of that module
2. I do not think you can exit a module - by the way what does it mean at all?
When you import a module it will be available. And when you execute del module, it won't be available any more, but it won't work in case of from module import something.

dugan · 07-03-2016, 12:18 AM

You don't need p if it's just to store the length of the list. And the Pythonic way to do this would be with a list comprehension. Note the use of enumerate to iterate over the list and get both the index and the value at that index.

Code:

>>> values = [150, 320, 120, 550, 630]
>>> values = [[value, index] for index, value in enumerate(values)]
>>> values
[[150, 0], [320, 1], [120, 2], [550, 3], [630, 4]]

I'm also having trouble understanding what you mean by "re-import". Python 2 had a "reload" keyword, which I think may be what you're thinking of. It's changed in Python 3. Here's a link about that:

http://stackoverflow.com/q/961162/240515