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how to find host name from IP with out login to the host
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Use nslookup
nslookup 208.77.188.166
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Non-authoritative answer:
166.188.77.208.in-addr.arpa name = www.example.com.
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Regex how to match an optional character
...e letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})
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How to determine if a point is in a 2D triangle? [closed]
... d2 = sign(pt, v2, v3);
d3 = sign(pt, v3, v1);
has_neg = (d1 < 0) || (d2 < 0) || (d3 < 0);
has_pos = (d1 > 0) || (d2 > 0) || (d3 > 0);
return !(has_neg && has_pos);
}
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C++ preprocessor __VA_ARGS__ number of arguments
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90
This is actually compiler dependent, and not supported by any standard.
Here however you have a...
What is a regular expression for a MAC Address?
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The standard (IEEE 802) format for
printing MAC-48 addresses in
human-friendly form is six groups of
two hexadecimal digits, separated by
hyphens - or colons :.
So:
^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$
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Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Convert list of dictionaries to a pandas DataFrame
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1044
Supposing d is your list of dicts, simply:
df = pd.DataFrame(d)
Note: this does not work with...
How can I convert a zero-terminated byte array to string?
I need to read [100]byte to transfer a bunch of string data.
13 Answers
13
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Matplotlib - global legend and title aside subplots
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edited Mar 13 at 17:30
answered Feb 10 '12 at 0:47
orb...
How do I generate random numbers in Dart?
...h:
import 'dart:math';
main() {
var rng = new Random();
for (var i = 0; i < 10; i++) {
print(rng.nextInt(100));
}
}
This code was tested with the Dart VM and dart2js, as of the time of this writing.
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