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Logical operators for boolean indexing in Pandas
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3 Answers
3
Active
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How to check if a string is a valid hex color representation?
... -> match end
i -> ignore case
If you need support for 3-character HEX codes, use the following:
/^#([0-9A-F]{3}){1,2}$/i.test('#ABC')
The only difference here is that
[0-9A-F]{6}
is replaced with
([0-9A-F]{3}){1,2}
This means that instead of matching exactly 6 charact...
What does numpy.random.seed(0) do?
..., 0.65, 0.44, 0.89])
>>> numpy.random.rand(4)
array([ 0.96, 0.38, 0.79, 0.53])
(pseudo-)random numbers work by starting with a number (the seed), multiplying it by a large number, adding an offset, then taking modulo of that sum. The resulting number is then used as the seed to gen...
Pandas groupby: How to get a union of strings
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In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own function, t...
How to insert element into arrays at specific position?
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23 Answers
23
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How to define a two-dimensional array?
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1039
You're technically trying to index an uninitialized array. You have to first initialize the out...
Could not locate Gemfile
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JoniJoni
2,85733 gold badges2121 silver badges2222 bronze badges
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Simple C example of doing an HTTP POST and consuming the response
...received, total;
char message[1024],response[4096];
if (argc < 3) { puts("Parameters: <apikey> <command>"); exit(0); }
/* fill in the parameters */
sprintf(message,message_fmt,argv[1],argv[2]);
printf("Request:\n%s\n",message);
/* create the socket */
so...
Obfuscated C Code Contest 2006. Please explain sykes2.c
...g:
main(_) {
_^448 && main(-~_);
putchar(--_%64
? 32 | -~7[__TIME__-_/8%8][">'txiZ^(~z?"-48] >> ";;;====~$::199"[_*2&8|_/64]/(_&2?1:8)%8&1
: 10);
}
Introducing variables to untangle this mess:
main(int i) {
if(i^448)
main(-~i);
...