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Why does changing 0.1f to 0 slow down performance by 10x?
Why does this bit of code,
5 Answers
5
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Python loop that also accesses previous and next values
How can I iterate over a list of objects, accessing the previous, current, and next items? Like this C/C++ code, in Python?
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MySQL check if a table exists without throwing an exception
... best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
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How to efficiently count the number of keys/properties of an object in JavaScript?
...at's the fastest way to count the number of keys/properties of an object? It it possible to do this without iterating over the object? i.e. without doing
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How to get the last N rows of a pandas DataFrame?
... dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') :
3 Answers
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Iterating over each line of ls -l output
I want to iterate over each line in the output of: ls -l /some/dir/*
6 Answers
6
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Completion handler for UINavigationController “pushViewController:animated”?
...pp using a UINavigationController to present the next view controllers.
With iOS5 there´s a new method to presenting UIViewControllers :
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Reading specific lines only
...lose()
Note that i == n-1 for the nth line.
In Python 2.6 or later:
with open("file") as fp:
for i, line in enumerate(fp):
if i == 25:
# 26th line
elif i == 29:
# 30th line
elif i > 29:
break
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What is Java String interning?
What is String Interning in Java, when I should use it, and why ?
7 Answers
7
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How to check for null in Twig?
...ned:
{% if var is not defined %}
{# do something #}
{% endif %}
Additionally the is sameas test, which does a type strict comparison of two values, might be of interest for checking values other than null (like false):
{% if var is sameas(false) %}
{# do something %}
{% endif %}
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