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What are “named tuples” in Python?
...tances can be referenced using object-like variable dereferencing or the standard tuple syntax. They can be used similarly to struct or other common record types, except that they are immutable. They were added in Python 2.6 and Python 3.0, although there is a recipe for implementation in Python 2...
What's the difference between == and .equals in Scala?
What is the difference between == and .equals() in Scala, and when to use which?
5 Answers
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RGB to hex and hex to RGB
How to convert colors in RGB format to hex format and vice versa?
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Java regex capturing groups indexes
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Capturing and grouping
Capturing group (pattern) creates a group that has capturing property.
A related one that you might often see (and use) is (?:pattern), which creates a group without capturing property, hence named non-capturi...
Abort makefile if variable not set
...ning an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defin...
Should you always favor xrange() over range()?
...might prefer range():
In python 3, range() does what xrange() used to do and xrange() does not exist. If you want to write code that will run on both Python 2 and Python 3, you can't use xrange().
range() can actually be faster in some cases - eg. if iterating over the same sequence multiple time...
How do I check if a number evaluates to infinity?
...lert(x === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should expect odd things to happen.)
– LukeH
Jan 18 '11 at 13:49
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iReport not starting using JRE 8
I have downloaded and installed the iReport 4.5 using te Windows installer. But when I try to start the iReport it shows the splash screen but does not start.
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Adding new column to existing DataFrame in Python pandas
I have the following indexed DataFrame with named columns and rows not- continuous numbers:
24 Answers
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What are the effects of exceptions on performance in Java?
Question: Is exception handling in Java actually slow?
18 Answers
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