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Remove duplicated rows using dplyr
...mple(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need...
Command-line Tool to find Java Heap Size and Memory Used (Linux)?
Is there a Command-line Tool (Linux) to check Heap Size (and Used Memory) of a Java Application?
17 Answers
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How do you scroll up/down on the Linux console?
I recognize that Up / Down will give you the command history. But, how do you look at past output by scrolling up and down?
...
Sending emails in Node.js? [closed]
... github.com/marak/node_mailer is deprecated. Should use this github.com/andris9/Nodemailer
– user470370
Jul 31 '12 at 6:17
...
Quickest way to convert a base 10 number to any base in .NET?
I have and old(ish) C# method I wrote that takes a number and converts it to any base:
12 Answers
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find: missing argument to -exec
I was helped out today with a command, but it doesn't seem to be working. This is the command:
10 Answers
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Differences between numpy.random and random.random in Python
.... I inspired myself in other people's code so I ended up using the numpy.random module for some things (for example for creating an array of random numbers taken from a binomial distribution) and in other places I use the module random.random .
...
Is python's sorted() function guaranteed to be stable?
..., the intention of the manual is indeed to guarantee that sorted is stable and indeed that it uses exactly the same algorithm as the sort method. I do realize that the docs aren't 100% clear about this identity; doc patches are always happily accepted!
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Image Greyscale with CSS & re-color on mouse-over?
I am looking to take an icon that is colored (and will be a link) and turn it greyscale until the user places their mouse over the icon (where it would then color the image).
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How to calculate a logistic sigmoid function in Python?
...uld do it:
import math
def sigmoid(x):
return 1 / (1 + math.exp(-x))
And now you can test it by calling:
>>> sigmoid(0.458)
0.61253961344091512
Update: Note that the above was mainly intended as a straight one-to-one translation of the given expression into Python code. It is not t...