How to read file into list in Python?

General Discussions
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1

How do you read a file into a list in Python?

I want to prompt a user to generate a set of random numbers and save them to a file. The task is to open that file, read the numbers, convert them into a list, and calculate the mean, standard deviation, etc., without using Python’s built-in tools.

I tried using the open function, but I encountered syntax errors. For example, I saved the file as “numbers” in “My Documents” and attempted open(numbers, 'r') and open(C:\name\MyDocuments\numbers, 'r'), but neither approach worked.

How can I handle this with Python read file into list?

2

I’ve worked with Selenium for quite some time, and Thread.sleep() is something I’ve encountered quite often. It’s best used when you need a quick and dirty way to pause the execution for a fixed amount of time.

For example:

from selenium import webdriver  
import time  

driver = webdriver.Chrome()  
driver.get('http://example.com')  

time.sleep(5)  # Pause for 5 seconds to wait for the page to load fully  

driver.quit()

Explanation: Thread.sleep() is useful when dealing with scenarios where explicit waits or other synchronization methods aren’t viable. It’s simple and effective for short pauses, but it’s not the most efficient or reliable way to wait, especially in dynamic web environments.

3

Adding to Vindhya’s point, while Thread.sleep() can serve as a quick solution, it’s better to use it sparingly. For dynamic websites, a more robust approach would be using Selenium’s explicit waits, which handle elements based on their state.

For example:

from selenium import webdriver  
from selenium.webdriver.common.by import By  
from selenium.webdriver.support.ui import WebDriverWait  
from selenium.webdriver.support import expected_conditions as EC  

driver = webdriver.Chrome()  
driver.get('http://example.com')  

try:
    element = WebDriverWait(driver, 10).until(  
        EC.presence_of_element_located((By.ID, 'exampleElement'))  
    )  
    print("Element is ready!")  
except:
    print("Element not found within the time frame")  

driver.quit()

Explanation: Explicit waits are more dynamic and adaptable than Thread.sleep(). They pause execution only until the required condition is met or until the timeout expires. This reduces unnecessary waiting and improves overall efficiency.

4

Both Vindhya and Emma have nailed the core points! Here’s an additional layer to the conversation: while Thread.sleep() and explicit waits serve their purposes, Selenium’s implicit waits offer another dimension of flexibility.

For example:

from selenium import webdriver  

driver = webdriver.Chrome()  
driver.implicitly_wait(10)  # Set a global wait time of 10 seconds  

driver.get('http://example.com')  

# Selenium will wait up to 10 seconds for elements to be available
element = driver.find_element(By.ID, 'exampleElement')  
print("Element is ready!")

driver.quit()

Explanation: Implicit waits make the WebDriver poll the DOM for a set duration to locate elements. This method is simple to implement and works well in situations where all elements have similar load times. However, it’s less granular than explicit waits, so combining both methods can lead to optimal results in most scenarios.