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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...
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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Which version of PostgreSQL am I running?
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1674
Run this query from PostgreSQL:
SELECT version();
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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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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...
Equivalent of jQuery .hide() to set visibility: hidden
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433
You could make your own plugins.
jQuery.fn.visible = function() {
return this.css('visibi...
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...
Zip lists in Python
...amine the length of the first element:
In [3]: result = zip(a, b, c)
In [4]: len(result[0])
Out[4]: 3
Of course, this won't work if the lists were empty to start with.
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How different is Scrum practice from Agile Practice? [duplicate]
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edited Jun 15 '13 at 4:00
answered Oct 19 '09 at 4:28
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