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Unix command to find lines common in two files
...)-release
Copyright (C) 2007 Free Software Foundation, Inc.
$ cat > abc
123
567
132
$ cat > def
132
777
321
So the files abc and def have one line in common, the one with "132".
Using comm on unsorted files:
$ comm abc def
123
132
567
132
777
321
$ comm -12 abc def # No output! ...
How to select the row with the maximum value in each group
...
The most intuitive method is to use group_by and top_n function in dplyr
group %>% group_by(Subject) %>% top_n(1, pt)
The result you get is
Source: local data frame [3 x 3]
Groups: Subject [3]
Subject pt Event
(dbl) (dbl) (dbl)
1 ...
How do I set default values for functions parameters in Matlab?
... use "varargs" and check against the number of arguments. Something like:
function f(arg1, arg2, arg3)
if nargin < 3
arg3 = 'some default'
end
end
There are a few fancier things you can do with isempty, etc., and you might want to look at Matlab central for some packages that bundl...
Is it worth using Python's re.compile?
...
dF.dF.
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How to break out of nested loops?
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No, don't spoil the fun with a break. This is the last remaining valid use of goto ;)
If not this then you could use flags to break out of deep nested loops.
Another approach to breaking out of a nested loop is to factor out both loops into ...
Java: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification
I have a class that will download a file from a https server. When I run it, it returns a lot of errors. It seems that I have a problem with my certificate. Is it possible to ignore the client-server authentication? If so, how?
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Base 64 encode and decode example code
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For Kotlin mb better to use this:
fun String.decode(): String {
return Base64.decode(this, Base64.DEFAULT).toString(charset("UTF-8"))
}
fun String.encode(): String {
return Base64.encodeToString(this.toByteArray(charset("UTF-8")), Base64.DEFAULT)
}
...
Fastest way to determine if an integer's square root is an integer
... if( x == 0 )
return true;
// Check mod 255 = 3 * 5 * 17, for fun
int64 y = x;
y = (y & 4294967295LL) + (y >> 32);
y = (y & 65535) + (y >> 16);
y = (y & 255) + ((y >> 8) & 255) + (y >> 16);
if( bad255[y] )
return false;...
C# member variable initialization; best practice?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
How do I check to see if a value is an integer in MySQL?
...NED ) // will return 0 if not numeric string.
for example
SELECT CAST('a123' AS UNSIGNED) // returns 0
SELECT CAST('123' AS UNSIGNED) // returns 123 i.e. > 0
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