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How to form tuple column from two columns in Pandas
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208
Get comfortable with zip. It comes in handy when dealing with column data.
df['new_col'] = li...
What's the fastest way to merge/join data.frames in R?
...he first example sqldf is 3x slower than data.table and in the second its 200x faster than plyr and 100 times faster than data.table. Below we show the input code, the output timings for the merge and the output timings for the aggregate. Its also worthwhile noting that sqldf is based on a databa...
How do I get an object's unqualified (short) class name?
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jeremysawesome
6,15733 gold badges3030 silver badges3232 bronze badges
answered Nov 11 '13 at 15:09
lonesomedaylonesomeday
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How can I convert a Unix timestamp to DateTime and vice versa?
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1059
Here's what you need:
public static DateTime UnixTimeStampToDateTime( double unixTimeStamp )
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The $.param( ) inverse function in JavaScript / jQuery
...eparam
– Felipe Castro
Jan 8 '13 at 0:52
2
Unfortunately the github page hasn't seen any updates ...
How can I quickly sum all numbers in a file?
...;
}
-e syntax OK
Just for giggles, I tried this with a file containing 1,000,000 numbers (in the range 0 - 9,999). On my Mac Pro, it returns virtually instantaneously. That's too bad, because I was hoping using mmap would be really fast, but it's just the same time:
use 5.010;
use File::Map qw(ma...
In php, is 0 treated as empty?
...ollowing things are considered to be empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (an empty array)
var $var; (a variable declared, but without a value in a class)
Note that this is exactly the same list as for a ...
How to iterate for loop in reverse order in swift?
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With Swift 2.0 it is now: 5.stride(to: 1, by: -1) or 5.stride(through: 1, by: -1)
– Binarian
Sep 21 '15 at 9:23
6
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Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space
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Be aware, that \W leaves the underscore. A short equivalent for [^a-zA-Z0-9] would be [\W_]
text.replace(/[\W_]+/g," ");
\W is the negation of shorthand \w for [A-Za-z0-9_] word characters (including the underscore)
Example at regex101.com
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Does JavaScript have a method like “range()” to generate a range within the supplied bounds?
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Numbers
[...Array(5).keys()];
=> [0, 1, 2, 3, 4]
Character iteration
String.fromCharCode(...[...Array('D'.charCodeAt(0) - 'A'.charCodeAt(0) + 1).keys()].map(i => i + 'A'.charCodeAt(0)));
=> "ABCD"
Iteration
for (const x of Array(5).keys()) {
co...