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Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
How do I move files in node.js?
...e rename function to do that.
http://nodejs.org/docs/latest/api/fs.html#fs_fs_rename_oldpath_newpath_callback
fs.rename(oldPath, newPath, callback)
Added in: v0.0.2
oldPath <String> | <Buffer>
newPath <String> | <Buffer>
callback <Function>
Asynchronous...
Escape angle brackets in a Windows command prompt
... containing angle brackets (< and >) to a file on a Windows machine. Basically what I want to do is the following:
echo some string < with angle > brackets >>myfile.txt
...
Why doesn't print work in a lambda?
...ed print function if you are using the latest Python 2.x:
In [1324]: from __future__ import print_function
In [1325]: f = lambda x: print(x)
In [1326]: f("HI")
HI
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Where can I find my .emacs file for Emacs running on Windows?
I tried looking for the .emacs file for my Windows installation for Emacs, but I could not find it. Does it have the same filename under Windows as in Unix?
...
How do I force Postgres to use a particular index?
...of why and what you can do instead can be found here. The reasons are basically that it's a performance hack that tends to cause more problems later down the line as your data changes, whereas PostgreSQL's optimizer can re-evaluate the plan based on the statistics. In other words, what might be a go...
C++ templates that accept only certain types
...ply forward-declare a global template, but only define (explicitly or partially specialise) it for the valid types:
template<typename T> class my_template; // Declare, but don't define
// int is a valid type
template<> class my_template<int> {
...
};
// All pointer types...
Getting multiple keys of specified value of a generic Dictionary?
...e, perhaps maintain two dictionary mapping key->value and value->List_of_keys. If you do the latter you will trade storage for look up speed. It wouldn't take much to turn @Cybis example into such a data structure.
s...
When to use IMG vs. CSS background-image?
...ng icon. This ensures that the meaning of the image can be communicated in all user-agents, including screen readers.
Pragmatic uses of IMG
Use IMG plus alt attribute if the image
is part of the content such as a logo or diagram or person (real person, not stock photo people).
—sanchothefat...
Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...roblem . After a long search I found a comment which had been ignored by all users pointing to the missing lib. Now, many months later, the comment has been changed to an answer. However, when I answered this question by msyself I intended to help other people by directly providing the solution. T...