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How do I create an average from a Ruby array?
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20 Answers
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RegEx for matching UK Postcodes
...nition given.
The RegEx supplied by the UK Government was:
([Gg][Ii][Rr] 0[Aa]{2})|((([A-Za-z][0-9]{1,2})|(([A-Za-z][A-Ha-hJ-Yj-y][0-9]{1,2})|(([A-Za-z][0-9][A-Za-z])|([A-Za-z][A-Ha-hJ-Yj-y][0-9][A-Za-z]?))))\s?[0-9][A-Za-z]{2})
As pointed out on the Wikipedia discussion, this will allow some no...
Is it better to call ToList() or ToArray() in LINQ queries?
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Tim Schmelter
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answered May 1 '13 at 17:42
JaredParJaredPar
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Determine the data types of a data frame's columns
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220
Your best bet to start is to use ?str(). To explore some examples, let's make some data:
set...
What is the difference between float and double?
...re calculated:
double has 52 mantissa bits + 1 hidden bit: log(253)÷log(10) = 15.95 digits
float has 23 mantissa bits + 1 hidden bit: log(224)÷log(10) = 7.22 digits
This precision loss could lead to greater truncation errors being accumulated when repeated calculations are done, e.g.
float a = 1...
Replace all 0 values to NA
I have a dataframe with some numeric columns. Some row has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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What is the bower (and npm) version syntax?
...ke any subsequent patch-level changes on the 1.2.x tree, starting with 1.2.0, but less than 1.3.0, you could use:
"angular": "~1.2"
or:
"angular": "~1.2.0"
This also gets you the same results as using the .x syntax:
"angular": "1.2.x"
But, you can use the tilde/~ syntax to be even more spec...
Permutations in JavaScript?
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108
If you notice, the code actually splits the chars into an array prior to do any permutation, so...
Pandas index column title or name
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In [8]: df.index.name = 'foo'
In [9]: df.index.name
Out[9]: 'foo'
In [10]: df
Out[10]:
Column 1
foo
Apples 1
Oranges 2
Puppies 3
Ducks 4
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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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