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What is the difference between printf() and puts() in C?
I know you can print with printf() and puts() . I can also see that printf() allows you to interpolate variables and do formatting.
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is_file or file_exists in PHP
...rk to work, you should add clearstatcache(); since the results for is_file and file_exists are cached throughout the script. Anyways file_exists() is a bit slower, but shouldn't make any difference unless you perform around 100K file checks. php.net/manual/en/function.clearstatcache.php
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Creating a new directory in C
... directory; if that directory does not exist then it creates the directory and a log file inside of it, but if the directory already exists, then it just creates a new log file in that folder.
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Replace None with NaN in pandas dataframe
... which will replace the Python object None, not the string 'None'.
import pandas as pd
import numpy as np
For dataframe:
df = df.fillna(value=np.nan)
For column or series:
df.mycol.fillna(value=np.nan, inplace=True)
share...
android EditText - finished typing event
...into/onto the next editable field - I pretty much never press Enter/Done - and what I've seen from our customers, neither do they... I am talking about a list of Edittexts/Comboboxes etc. If you only give the user one Input field and force him to press a button before he can advance to other fields ...
Does Python optimize tail recursion?
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No, and it never will since Guido van Rossum prefers to be able to have proper tracebacks:
Tail Recursion Elimination (2009-04-22)
Final Words on Tail Calls (2009-04-27)
You can manually eliminate the recursion with a transfor...
How to search in array of object in mongodb
...hout $elemMatch mongo will look for users with National Medal in some year and some award in 1975s, but not for users with National Medal in 1975.
See MongoDB $elemMatch Documentation for more info. See Read Operations Documentation for more information about querying documents with arrays.
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How can I set NODE_ENV=production on Windows?
...tained), use
set NODE_ENV=production
This should be executed in the command prompt where you intend to run your Node.js application.
The above line would set the environment variable NODE_ENV for the command prompt where you execute the command.
To set environment variables globally so they per...
What exactly is Python multiprocessing Module's .join() Method Doing?
Learning about Python Multiprocessing (from a PMOTW article ) and would love some clarification on what exactly the join() method is doing.
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Find all controls in WPF Window by type
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Note: If you're trying to get this to work and finding that your Window (for instance) has 0 visual children, try running this method in the Loaded event handler. If you run it in the constructor (even after InitializeComponent()), the visual children aren't loaded y...