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How do I calculate square root in Python?
...ve to write: sqrt = x**(1/2.0), otherwise an integer division is performed and the expression 1/2 returns 0.
This behavior is "normal" in Python 2.x, whereas in Python 3.x 1/2 evaluates to 0.5. If you want your Python 2.x code to behave like 3.x w.r.t. division write from __future__ import division...
How do I use itertools.groupby()?
I haven't been able to find an understandable explanation of how to actually use Python's itertools.groupby() function. What I'm trying to do is this:
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RE error: illegal byte sequence on Mac OS X
...for cross-compiling to iOS. The string has embedded double quotes. The command is:
7 Answers
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Getting command-line password input in Python
...w in Linux when you try some Sudo stuff it tells you to enter the password and, as you type, nothing is shown in the terminal window (the password is not shown)?
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How to write a bash script that takes optional input arguments?
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You could use the default-value syntax:
somecommand ${1:-foo}
The above will, as described in Bash Reference Manual - 3.5.3 Shell Parameter Expansion [emphasis mine]:
If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of paramet...
In Python, how do I determine if an object is iterable?
... in our code as well for this purpose, but I've lately started to get more and more annoyed by objects which only have __getitem__ being considered iterable. There are valid reasons to have __getitem__ in a non-iterable object and with them the above code doesn't work well. As a real life example we...
Placement of the asterisk in pointer declarations
I've recently decided that I just have to finally learn C/C++, and there is one thing I do not really understand about pointers or more precisely, their definition.
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Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
... have read the quote :
data depends on the key [1NF], the whole key [2NF] and nothing but the key [3NF] .
6 Answers
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Setting environment variables on OS X
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Bruno is right on track. I've done extensive research and if you want to set variables that are available in all GUI applications, your only option is /etc/launchd.conf.
Please note that environment.plist does not work for applications launched via Spotlight. This is documented...
Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
In development blogs, online code examples and (recently) even a book, I keep stumbling about code like this:
13 Answers
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