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How to drop columns by name in a data frame
... subset(dtest, select = names(dtest)[!names(dtest) %in% drop_vec]) 108.611 119.4830 124.0865 135.4270 1599.577
subset(dtest, select = -c(x, y)) 102.026 111.2680 115.7035 126.2320 1484.174
Code is below :
dtest <- data.frame(x=1:5, y=2:6, z = 3:7)
drop_vec ...
How can I pipe stderr, and not stdout?
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@KurtPfeifle: au contraire! One must read the redirection chains from left to right since that is the way the shell processes them. The f...
Surrogate vs. natural/business keys [closed]
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Tony AndrewsTony Andrews
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How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
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David HedlundDavid Hedlund
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Fastest way to determine if an integer's square root is an integer
...e same technique in Java once you get the idea:
I originally found it at: http://www.codemaestro.com/reviews/9
Newton's method explained at wikipedia: http://en.wikipedia.org/wiki/Newton%27s_method
You can follow the link for more explanation of how it works, but if you don't care much, then this...
switch / pattern matching idea
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Greg BeechGreg Beech
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How do you set, clear, and toggle a single bit?
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It is sometimes worth using an enum to name the bits:
enum ThingFlags = {
ThingMask = 0x00...
What's the point of OOP?
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119
votes
The real world isn't "OO", and the idea implicit in OO--that we can mode...
Why is XOR the default way to combine hashes?
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Assuming uniformly random (1-bit) inputs, the AND function output probability distribution is ...
What are the dangers when creating a thread with a stack size of 50x the default?
....80 %| 120.72 %|
--+---------+---------+---------+
G | 99.21 %| - | 119.76 %|
--+---------+---------+---------+
H | 82.84 %| 83.50 %| - |
--+---------+---------+---------+
Rates are calculated by dividing the row's value to the column's.
I tested on Windows 8.1 Pro (with Update 1), ...