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Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...
Java HashMap performance optimization / alternative
...or every object:
public int hashCode() {
// assume that both a and b are sorted
return a[0] + powerOf52(a[1], 1) + powerOf52(b[0], 2) + powerOf52(b[1], 3) + powerOf52(b[2], 4);
}
public static int powerOf52(byte b, int power) {
int result = b;
for (int i = 0; i < p...
How to pip install a package with min and max version range?
...tall a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
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How do I split a string so I can access item x?
...ourceText)) SET @w_Length = DATALENGTH( RTRIM( LTRIM( @p_SourceText))) and not SET @p_SourceText = RTRIM( LTRIM( @p_SourceText)) SET @w_Length = DATALENGTH( @p_SourceText)?
– Beth
Sep 29 '10 at 15:13
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Generate random int value from 3 to 6
Is it possible in Microsoft SQL Server generate random int value from Min to Max (3-9 example, 15-99 e.t.c)
10 Answers
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Javascript and regex: split string and keep the separator
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I don't understand why everybody is using /g
– Sarsaparilla
Jan 11 '17 at 18:22
1
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How can I troubleshoot my Perl CGI script?
I have a Perl script that isn't working and I don't know how to start narrowing down the problem. What can I do?
8 Answers
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Python progression path - From apprentice to guru
I've been learning, working, and playing with Python for a year and a half now. As a biologist slowly making the turn to bio-informatics, this language has been at the very core of all the major contributions I have made in the lab. I more or less fell in love with the way Python permits me to expre...
How to sort an array in Bash
...set IFS
Supports whitespace in elements (as long as it's not a newline), and works in Bash 3.x.
e.g.:
$ array=("a c" b f "3 5")
$ IFS=$'\n' sorted=($(sort <<<"${array[*]}")); unset IFS
$ printf "[%s]\n" "${sorted[@]}"
[3 5]
[a c]
[b]
[f]
Note: @sorontar has pointed out that care is re...
Wolfram's Rule 34 in XKCD [closed]
...1110. The digit of least significance is zero. This means that if the cell and its neighbors match rule 0 above, it turns white/negative/0/false/whatever. The second least significant digit is one, so if the cell and its neighbors match rule 1 above, it turns black/positive/1/true/whatever`, etc. et...