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How can I check for Python version in a program that uses new language features?
If I have a Python script that requires at least a particular
version of Python, what is the correct way to fail gracefully
when an earlier version of Python is used to launch the script?
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Can an enum class be converted to the underlying type?
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I think you can use std::underlying_type to know the underlying type, and then use cast:
#include <type_traits> //for std::underlying_type
typedef std::underlying_type<my_fields>::type utype;
utype a = static_cast<utype>(my_fields::field);
With th...
addEventListener not working in IE8
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Try:
if (_checkbox.addEventListener) {
_checkbox.addEventListener("click", setCheckedValues, false);
}
else {
_checkbox.attachEvent("onclick", setCheckedValues);
}
Update::
For Internet Explorer versions prior to IE9, at...
Mean per group in a data.frame [duplicate]
..."Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))
Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name):
First, decide which columns you want to take the mean of
colstoavg <- names(mydt)[3:4]
Now we use lapply to take the mean over the column...
Does Python support short-circuiting?
...or in operator and, or:
Let's first define a useful function to determine if something is executed or not. A simple function that accepts an argument, prints a message and returns the input, unchanged.
>>> def fun(i):
... print "executed"
... return i
...
One can observe the P...
Name node is in safe mode. Not able to leave
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Updated my answer as per new distributions, if anyone can help us out in establishing the exact version of apache hadoop since when these deprecations have come into picture, it would be great.
– Amar
Mar 19 '14 at 19:03
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php $_POST array empty upon form submission
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@ŁukaszBachman How to do that if dataobject is something like........title=something&body=anything. I want to get the vale of title & body. $dataobject["title"] returns empty. In my case $_POST is empty. And the only way to get it using file_get_c...
Eclipse IDE: How to zoom in on text?
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It is now a official feature in Neon: eclipse.org/eclipse/news/4.6/platform.php
– gustavovelascoh
Nov 26 '16 at 1:42
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How to validate an email address using a regular expression?
...me web page as was the address.
Confirmation tokens are the only way to know you got the address of the person entering it. This is why most mailing lists now use that mechanism to confirm sign-ups. After all, anybody can put down president@whitehouse.gov, and that will even parse as legal, but it...
Override setter with arc
...ary as you don't do more than the standard generated setter would do? Only if you add more code to setImageURLString: would you need to override the setter.
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