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Regular expression for a hexadecimal number?
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How about the following?
0[xX][0-9a-fA-F]+
Matches expression starting with a 0, following by either a lower or uppercase x, followed by one or more characters in the ranges 0-9, or a-f, or A-F
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How to read data when some numbers contain commas as thousand separator?
...", and then convert the string to numeric using as.numeric:
y <- c("1,200","20,000","100","12,111")
as.numeric(gsub(",", "", y))
# [1] 1200 20000 100 12111
This was also answered previously on R-Help (and in Q2 here).
Alternatively, you can pre-process the file, for instance with sed in unix...
How to find Unused Amazon EC2 Security groups
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edited Jul 1 at 20:15
Dherik
11.2k1010 gold badges7373 silver badges114114 bronze badges
answer...
What is the default value for enum variable?
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It is whatever member of the enumeration represents the value 0. Specifically, from the documentation:
The default value of an enum E is the value produced by the expression (E)0.
As an example, take the following enum:
enum E
{
Foo, Bar, Baz, Quux
}
Without overriding the ...
vertical & horizontal lines in matplotlib
...is range, regardless of coordinates. The parameters xmin or ymin use value 0.0 as the minimum of the axis and 1.0 as the maximum of the axis.
Instead, use plt.plot((x1, x2), (y1, y2), 'k-') to draw a line from the point (x1, y1) to the point (x2, y2) in color k. See pyplot.plot.
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Get the current year in JavaScript
...ily: sans-serif;
}
<footer>
&copy; <span id="year">2018</span> by FooBar
</footer>
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How to run cron once, daily at 10pm
...2 I guess. Try the following to run it every first minute of the hour 22:
0 22 * * * ....
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How can I get a count of the total number of digits in a number?
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Without converting to a string you could try:
Math.Ceiling(Math.Log10(n));
Correction following ysap's comment:
Math.Floor(Math.Log10(n) + 1);
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Undefined method 'task' using Rake 0.9.0
I just updated Rake to the latest version ( 0.9.0.beta.4 ) and the rake command ends up with the following error message:
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