I’m building a simple interpreter in python and I’m having trouble handling differing numbers of arguments to my functions. My current method is to get a list of the commands/arguments as follows. Then to execute com, I check to see if it is in my dictionary of command-> code mappings and if it is I call the function I have
Tag: list
List Directories and get the name of the Directory
I am trying to get the code to list all the directories in a folder, change directory into that folder and get the name of the current folder. The code I have so far is below and isn’t working at the minute. I seem to be getting the parent folder name. I also have other files in the folder but
Getting next element while cycling through a list
When this reaches the last element, an IndexError is raised (as is the case for any list, tuple, dictionary, or string that is iterated). I actually want at that point for nextelem to equal li[0]. My rather cumbersome solution to this was Is there a better way of doing this? Answer After thinking this through carefully, I think this is
Splitting a list into N parts of approximately equal length
What is the best way to divide a list into roughly equal parts? For example, if the list has 7 elements and is split it into 2 parts, we want to get 3 elements in one part, and the other should have 4 elements. I’m looking for something like even_split(L, n) that breaks L into n parts. The code above
Convert NumPy array to Python list
How do I convert a NumPy array into a Python List? Answer Use tolist(): Note that this converts the values from whatever numpy type they may have (e.g. np.int32 or np.float32) to the “nearest compatible Python type” (in a list). If you want to preserve the numpy data types, you could call list() on your array instead, and you’ll end
How do I concatenate two lists in Python?
This question’s answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions. How do I concatenate two lists in Python? Example: Expected outcome: Answer Use the + operator to combine the lists: Output:
Python: return the index of the first element of a list which makes a passed function true
The list.index(x) function returns the index in the list of the first item whose value is x. Is there a function, list_func_index(), similar to the index() function that has a function, f(), as a parameter. The function, f() is run on every element, e, of the list until f(e) returns True. Then list_func_index() returns the index of e. Codewise: Is
How can I compare two lists in python and return matches [duplicate]
This question already has answers here: How do I iterate through two lists in parallel? (8 answers) How to find list intersection? (16 answers) Closed 5 months ago. I want to take two lists and find the values that appear in both. would return [5], for instance. Answer Not the most efficient one, but by far the most obvious way
Shuffling a list of objects
How do I shuffle a list of objects? I tried random.shuffle: But it outputs: Answer random.shuffle should work. Here’s an example, where the objects are lists: Note that shuffle works in place, and returns None. More generally in Python, mutable objects can be passed into functions, and when a function mutates those objects, the standard is to return None (rather
How can I partition (split up, divide) a list based on a condition?
I have some code like: The goal is to split up the contents of mylist into two other lists, based on whether or not they meet a condition. How can I do this more elegantly? Can I avoid doing two separate iterations over mylist? Can I improve performance by doing so? Answer How can I do this more elegantly? That