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Putting an if-elif-else statement on one line?
...st likely violate PEP-8 where it is mandated that lines should not exceed 80 characters in length.
It's also against the Zen of Python: "Readability counts". (Type import this at the Python prompt to read the whole thing).
You can use a ternary expression in Python, but only for expressions, not f...
Frequency table for a single variable
...es = pandas.Series([1,2,2,3,3,3, "fred", 1.8, 1.8])
>>> my_series
0 1
1 2
2 2
3 3
4 3
5 3
6 fred
7 1.8
8 1.8
>>> counts = my_series.value_counts()
>>> counts
3 3
2 2
1.8 2
fred 1
1 1
>>> len(c...
Auto-center map with multiple markers in Google Maps API v3
...tLngBounds();
var infowindow = new google.maps.InfoWindow();
for (i = 0; i < locations.length; i++) {
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[i][1], locations[i][2]),
map: map
});
//extend the bounds to include each marker's position
...
Shell equality operators (=, ==, -eq)
... guaranteed to work.
$ a=foo
$ [ "$a" = foo ]; echo "$?" # POSIX sh
0
$ [ "$a" == foo ]; echo "$?" # bash specific
0
$ [ "$a" -eq foo ]; echo "$?" # wrong
-bash: [: foo: integer expression expected
2
(Side note: Quote those variable expansions! Do not leave out the double quotes ab...
Reset C int array to zero : the fastest way?
Assuming that we have a T myarray[100] with T = int, unsigned int, long long int or unsigned long long int, what is the fastest way to reset all its content to zero (not only for initialization but to reset the content several times in my program)? Maybe with memset?
...
How do I horizontally center an absolute positioned element inside a 100% width div? [duplicate]
... be horizontally centered within #header . Normally, I would do a margin:0 auto for relatively positioned elements but I am stuck here. Can someone show me the way?
...
Is there an easy way to check the .NET Framework version?
... to know if it's version 3.5 SP 1. Environment.Version() only returns 2.0.50727.3053 .
21 Answers
...
Python: Get the first character of the first string in a list?
...
You almost had it right. The simplest way is
mylist[0][0] # get the first character from the first item in the list
but
mylist[0][:1] # get up to the first character in the first item in the list
would also work.
You want to end after the first character (character z...
Global access to Rake DSL methods is deprecated
...t refers to a @DHH tweet.
Put the following in your Gemfile
gem "rake", "0.8.7"
You may see something like
rake aborted!
You have already activated Rake 0.9.1 ...
I still had a copy of Rake 0.9.1 in my directory so I deleted it.
You can "delete" Rake 0.9.1 by running the following command: ...