I want to get the next item in queue but I don’t want to dequeue it. Is it possible in Python’s queue.PriorityQueue? From the docs, I don’t see how can it be done Answer When you get item form the queue as per theory it will remove from the queue. You have to write your own function which will give
Difference between multiple if’s and elif’s?
In python, is there a difference between say: and Just wondering if multiple ifs could cause any unwanted problems and if it would be better practice to use elifs. Answer Multiple if’s means your code would go and check all the if conditions, where as in case of elif, if one if condition satisfies it would not check other conditions..
Concatenating two one-dimensional NumPy arrays
How do I concatenate two one-dimensional arrays in NumPy? I tried numpy.concatenate: But I get an error: TypeError: only length-1 arrays can be converted to Python scalars Answer Use: The arrays you want to concatenate need to be passed in as a sequence, not as separate arguments. From the NumPy documentation: numpy.concatenate((a1, a2, …), axis=0) Join a sequence of arrays
In Python argparse, is it possible to have paired –no-something/–something arguments?
I’m writing a program in which I would like to have arguments like this: Is there a way to get argparse to do this for me? Answer v3.9 has added an action class that does this. From the docs (near the end of the action section) The BooleanOptionalAction is available in argparse and adds support for boolean actions such as
Memory dump formatted like xxd from gdb
I’m trying to inspect a buffer which contains a binary formatted message, but also contains string data. As an example, I’m using this C code: I’d like to get a hex dump of what’s in buf, of a format similar to xxd (I don’t care if it’s an exact match, what I’m really looking for is a hex dump side
Is python zipfile thread-safe?
In a django project, I need to generate some pdf files for objects in db. Since each file takes a few seconds to generate, I use celery to run tasks asynchronously. Problem is, I need to add each file to a zip archive. I was planning to use the python zipfile module, but different tasks can be run in different
How can I force Python’s file.write() to use the same newline format in Windows as in Linux (“rn” vs. “n”)?
I have the simple code: Code runs on windows and gives file size 12 bytes, and linux gives 11 bytes The reason is new line In linux it’s n and for win it is rn But in my code I specify new line as n. The question is how can I make python keep new line as n always, and
How do you get the magnitude of a vector in Numpy?
In keeping with the “There’s only one obvious way to do it”, how do you get the magnitude of a vector (1D array) in Numpy? The above works, but I cannot believe that I must specify such a trivial and core function myself. Answer The function you’re after is numpy.linalg.norm. (I reckon it should be in base numpy as a
Using a dictionary to select function to execute
I am trying to use functional programming to create a dictionary containing a key and a function to execute: Now, I have seen a code used to find the defined functions in a module, and I need to do something like this: So my question is, How do I make a list of all the Exec functions and then assign
How do I raise the same Exception with a custom message in Python?
I have this try block in my code: Strictly speaking, I am actually raising another ValueError, not the ValueError thrown by do_something…(), which is referred to as err in this case. How do I attach a custom message to err? I try the following code but fails due to err, a ValueError instance, not being callable: Answer Update: For Python