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How to drop a list of rows from Pandas dataframe?
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Use DataFrame.drop and pass it a Series of index labels:
In [65]: df
Out[65]:
one two
one 1 4
two 2 3
three 3 2
four 4 1
In [66]: df.drop(df.index[[1,3]])
Out[66]:
one two
one 1 4
three 3 2
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drag drop files into standard html file input
...ays we can drag & drop files into a special container and upload them with XHR 2. Many at a time. With live progress bars etc. Very cool stuff. Example here.
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Why can't decimal numbers be represented exactly in binary?
...n several questions posted to SO about floating-point representation. For example, the decimal number 0.1 doesn't have an exact binary representation, so it's dangerous to use the == operator to compare it to another floating-point number. I understand the principles behind floating-point representa...
How do I access this object property with an illegal name?
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<?php
$x = new StdClass();
$x->{'todo-list'} = 'fred';
var_dump($x);
So, $object->{'todo-list'} is the sub-object. If you can set it like that, then you can also read it the same way:
echo $x->{'todo-list'};
Another poss...
What do Clustered and Non clustered index actually mean?
I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes .
I googled and what I found was :
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“Private” (implementation) class in Python
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Use a single underscore prefix:
class _Internal:
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This is the official Python convention for 'internal' symbols; "from module import *" does not import underscore-prefixed objects.
Edit: Reference to the single underscore convention
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Trusting all certificates using HttpClient over HTTPS
...'ve run into new issues. As with my last problem, I can't seem to find an example anywhere that works for me. Basically, I want my client to accept any certificate (because I'm only ever pointing to one server) but I keep getting a javax.net.ssl.SSLException: Not trusted server certificate exceptio...
Generate colors between red and green for a power meter?
...hould work - just linearly scale the red and green values. Assuming your max red/green/blue value is 255, and n is in range 0 .. 100
R = (255 * n) / 100
G = (255 * (100 - n)) / 100
B = 0
(Amended for integer maths, tip of the hat to Ferrucio)
Another way to do would be to use a HSV colour model...
Converting an int to std::string
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@bparker Right, it's been fixed in gcc 4.8.0 I guess. MinGW coming with latest Code::Blocks (13.12) still has gcc 4.7.1.
– Archie
Dec 2 '15 at 16:24
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Return first N key:value pairs from dict
...no longer correct. Python dicts now preserve insertion order, and this is explicitly documented.
– Konrad Rudolph
Sep 22 at 12:30
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