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How can I brew link a specific version?
...h the available version numbers:
brew switch mysql 0
Update (15.10.2014):
The brew versions command has been removed from brew, but, if you do wish to use this command first run brew tap homebrew/boneyard.
The recommended way to install an old version is to install from the homebrew/versions ...
How do I interpret precision and scale of a number in a database?
...
406
Numeric precision refers to the maximum number of digits that are present in the number.
ie ...
How to drop columns by name in a data frame
... function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2
2 2 3
3 3 4...
How to get a URL parameter in Express?
...ue on getting the value of tagid from my URL: localhost:8888/p?tagid=1234 .
4 Answers
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Appropriate datatype for holding percent values?
...ent (e.g. 100.00% stored as 1.0000), I would store the data in a decimal(5,4) data type with a CHECK constraint that ensures that the values never exceed 1.0000 (assuming that is the cap) and never go below 0 (assuming that is the floor). If you are going to store their face value (e.g. 100.00% is s...
Tell Ruby Program to Wait some amount of time
... construct longer intervals using the following convenience syntax:
sleep(4.minutes)
# or, even longer...
sleep(2.hours); sleep(3.days) # etc., etc.
# or shorter
sleep(0.5) # half a second
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How to group dataframe rows into list in pandas groupby?
...
442
You can do this using groupby to group on the column of interest and then apply list to every ...
Split a vector into chunks in R
...(), split() and ceiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 12 4 6 8 4 2 7 6 5
[53] 4 5 4 5 5 8 7 7 7 6 2 4 3 3 8 11 6 6 1 8 4
> m...
Logical operators for boolean indexing in Pandas
...
answered Jan 28 '14 at 20:22
unutbuunutbu
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How do you grep a file and get the next 5 lines
How do I grep a file for 19:55 and get the Line 1,2,3,4,5?
3 Answers
3
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