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Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
...ferent sizes, a pattern came up. Invariably, transposing a matrix of size 2^n is slower than transposing one of size 2^n+1 . For small values of n , the difference is not major.
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Why is unsigned integer overflow defined behavior but signed integer overflow isn't?
...ed by both the C and C++ standards. For example, the C99 standard ( §6.2.5/9 ) states
5 Answers
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How get integer value from a enum in Rails?
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142
You can get the integer values for an enum from the class the enum is on:
Model.sale_infos # Pl...
Android adb “Unable to open sync connection!”
...t for doing this?
– James Moore
May 25 '11 at 16:06
1
Seriously why is android always so faulty!?...
Formatting code snippets for blogging on Blogger [closed]
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255
I've created a blog post entry which explains how to add code syntax highlighting to blogger u...
How can I get column names from a table in Oracle?
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25 Answers
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Active
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Automatic exit from bash shell script on error [duplicate]
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answered May 20 '10 at 4:36
Adam RosenfieldAdam Rosenfield
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How do you simulate Mouse Click in C#?
... [Flags]
public enum MouseEventFlags
{
LeftDown = 0x00000002,
LeftUp = 0x00000004,
MiddleDown = 0x00000020,
MiddleUp = 0x00000040,
Move = 0x00000001,
Absolute = 0x00008000,
RightDown = 0x00000008,
RightUp = 0x00000010
}
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Java: How to convert List to Map
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192
List<Item> list;
Map<Key,Item> map = new HashMap<Key,Item>();
for (Item i : li...
Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id": ...