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Applying a function to every row of a table using dplyr?
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alexwhanalexwhan
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How does zip(*[iter(s)]*n) work in Python?
...and it pulls an item from the iterator each time.
x = iter([1,2,3,4,5,6,7,8,9])
print zip(x, x, x)
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Determine the data types of a data frame's columns
...r(my.data)
'data.frame': 5 obs. of 4 variables:
$ y : num 1.03 1.599 -0.818 0.872 -2.682
$ x1: int 1 2 3 4 5
$ x2: logi TRUE TRUE FALSE FALSE FALSE
$ X3: Factor w/ 5 levels "a","b","c","d",..: 1 2 3 4 5
@Gavin Simpson's approach is also streamlined, but provides slightly different information...
Rank function in MySQL
...erson VALUES (5, 'Nick', 22, 'M');
INSERT INTO person VALUES (6, 'Kathy', 18, 'F');
INSERT INTO person VALUES (7, 'Steve', 36, 'M');
INSERT INTO person VALUES (8, 'Anne', 25, 'F');
Result:
+------------+------+--------+------+
| first_name | age | gender | rank |
+------------+------+--------+--...
Regular expression to match numbers with or without commas and decimals in text
...ure the whole thing wasn't blank.
Tested here: http://rextester.com/YPG96786
This will allow things like:
100,000
999.999
90.0009
1,000,023.999
0.111
.111
0
It will block things like:
1,1,1.111
000,001.111
999.
0.
111.110000
1.1.1.111
9.909,888
There are several ways to make this regex simpler an...
Bootstrap 3 offset on right not left
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Ross AllenRoss Allen
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Flatten an Array of Arrays in Swift
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448
Swift >= 3.0
reduce:
let numbers = [[1,2,3],[4],[5,6,7,8,9]]
let reduced = numbers.reduce([...
How to work around the stricter Java 8 Javadoc when using Maven
You'll quickly realize that JDK8 is a lot more strict (by default) when it comes to Javadoc. ( link - see last bullet point)
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Shuffle two list at once with same order
...an?
– ᔕᖺᘎᕊ
Apr 2 '15 at 16:18
2
@ᔕᖺᘎᕊ, It means unpack the values of c so it is c...
How to drop columns by name in a data frame
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389
You should use either indexing or the subset function. For example :
R> df <- data.frame...