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Get the Row(s) which have the max count in groups using groupby
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341
In [1]: df
Out[1]:
Sp Mt Value count
0 MM1 S1 a 3
1 MM1 S1 n 2
2 M...
Get week of year in JavaScript like in PHP
...eks of previous
* or next year, overlap is up to 3 days.
*
* e.g. 2014/12/29 is Monday in week 1 of 2015
* 2012/1/1 is Sunday in week 52 of 2011
*/
function getWeekNumber(d) {
// Copy date so don't modify original
d = new Date(Date.UTC(d.getFullYear(), d.getMonth(), d.ge...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
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MaheMahe
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Counting the number of elements with the values of x in a vector
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You can just use table():
> a <- table(numbers)
> a
numbers
4 5 23 34 43 54 56 65 67 324 435 453 456 567 657
2 1 2 2 1 1 2 1 2 1 3 1 1 1 1
Then you can subset it:
> a[names(a)==435]
435
3
Or convert it into a data.frame if you're mor...
Which version of PostgreSQL am I running?
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1674
Run this query from PostgreSQL:
SELECT version();
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What's the difference between a temp table and table variable in SQL Server?
...If you don't have a unique column, you can use an identity column.) SQL 2014 has non-unique indexes too.
Table variables don't participate in transactions and SELECTs are implicitly with NOLOCK. The transaction behaviour can be very helpful, for instance if you want to ROLLBACK midway through a proc...
How can I expand and collapse a using javascript?
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184
Okay, so you've got two options here :
Use jQuery UI's accordion - its nice, easy and fast. Se...
How do I escape spaces in path for scp copy in Linux?
...rian Gunawan
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13
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How to check the extension of a filename in a bash script?
...of $file equal to .txt?" If so, you can use the following:
if [ ${file: -4} == ".txt" ]
Note that the space between file: and -4 is required, as the ':-' modifier means something different.
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