Is the function "next" a good practice to find first occurrence in a iterable? Question: I’ve learned about iterators and such and discovered this quite interesting way of getting the first element in a list that a condition is applied (and also with default value in case we don’t find it): first_occurence = next((x for …
If True: turn following values to True in list of booleans until nth position after True is reached Question: I have a list of booleans l = [False, False, False, True, False, False, False] that I want to turn into l_new = [False, False, False, True, True, True, False] That means, whenever there is a …
What does next() and iter() do in PyTorch's DataLoader() Question: I have the following code: import torch import numpy as np import pandas as pd from torch.utils.data import TensorDataset, DataLoader # Load dataset df = pd.read_csv(r’../iris.csv’) # Extract features and target data = df.drop(‘target’,axis=1).values labels = df[‘target’].values # Create tensor dataset iris = TensorDataset(torch.FloatTensor(data),torch.LongTensor(labels)) # …
Using next() on generator function Question: I have this generator function:- def gen(): for i in range(3): yield i*i Now when I am calling next() on gen(), it is giving the first element each time. >>> next(gen()) 0 >>> next(gen()) 0 But when I use that in a for loop, it works as expected: >>> …
Why does a yield from inside __next__() return generator object? Question: I am using yield to return the next value in the __next__() function in my class. However it does not return the next value, it returns the generator object. I am trying to better understand iterators and yield. I might be doing it in …
How to solve "OSError: telling position disabled by next() call" Question: I am creating a file editing system and would like to make a line based tell() function instead of a byte based one. This function would be used inside of a “with loop” with the open(file) call. This function is part of a class …
iterrows pandas get next rows value Question: I have a df in pandas import pandas as pd df = pd.DataFrame([‘AA’, ‘BB’, ‘CC’], columns = [‘value’]) I want to iterate over rows in df. For each row i want rows value and next rows value Something like(it does not work): for i, row in df.iterrows(): print …
Skip multiple iterations in loop Question: I have a list in a loop and I want to skip 3 elements after look has been reached. In this answer a couple of suggestions were made but I fail to make good use of them: song = [‘always’, ‘look’, ‘on’, ‘the’, ‘bright’, ‘side’, ‘of’, ‘life’] for sing …
How to use scrapy for Amazon.com links after "Next" Button? Question: I am relatively new to Python and Scrapy. I’m trying to scrap the links in “Customers who bought this item also bought”. For example: http://www.amazon.com/Confessions-Economic-Hit-John-Perkins-ebook/dp/B001AFF266/. There are 17 pages for “Customers who bought this item also bought”. If I ask scrapy to scrap that …
django redirect after login not working "next" not posting? Question: I have a login page which is working fine with the exception of the redirect to the referrer page. The user gets an email with a direct link within the app, they (in this example) are not logged in already and are redirected to the …
