大约有 13,922 项符合查询结果(耗时:0.0257秒) [XML]
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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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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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...
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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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...
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...
“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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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...
Why is null an object and what's the difference between null and undefined?
...Script: I don't know.
In short; undefined is where no notion of the thing exists; it has no type, and it's never been referenced before in that scope; null is where the thing is known to exist, but it's not known what the value is.
One thing to remember is that null is not, conceptually, the same as...
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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