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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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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...
Mac OSX Lion DNS lookup order [closed]
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I think he matter is Lion handles .local TLD differently because it's reserved for some Multicast DNS features (used by Bonjour). The only way i found to solve this issue is using a different TLD for development hosts (ie: .dev). It works fine for me, ...
What does (x ^ 0x1) != 0 mean?
...expression is false if x == 1.
So the test is the same as:
if (x != 1)
and is therefore (arguably) unnecessarily obfuscated.
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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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Convert a Git folder to a submodule retrospectively?
Quite often it is the case that you're writing a project of some kind, and after a while it becomes clear that some component of the project is actually useful as a standalone component (a library, perhaps). If you've had that idea from early on, then there's a fair chance that most of that code is ...
How to resolve symbolic links in a shell script
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According to the standards, pwd -P should return the path with symlinks resolved.
C function char *getcwd(char *buf, size_t size) from unistd.h should have the same behaviour.
getcwd
pwd
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Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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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...
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...