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Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(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 fr...
Is it safe to check floating point values for equality to 0?
...ality between double or decimal type values normally, but I'm wondering if 0 is a special case.
9 Answers
...
Scaling Node.js
...like to know what the general principles are for scaling node up to, say, 20 queries per second.
1 Answer
...
how to mysqldump remote db from local machine
...
250
As I haven't seen it at serverfault yet, and the answer is quite simple:
Change:
ssh -f -L3310...
How to connect to my http://localhost web server from Android Emulator
...ct it to my localhost web server page at http://localhost or http://127.0.0.1 ?
11 Answers
...
How to sort a list in Scala by two fields?
...g.String) ).
– senia
Jun 18 '14 at 10:16
5
@SachinK: You could implement customOrdering as Orderi...
How to determine if a list of polygon points are in clockwise order?
...se. (The result is twice the enclosed area, with a +/- convention.)
point[0] = (5,0) edge[0]: (6-5)(4+0) = 4
point[1] = (6,4) edge[1]: (4-6)(5+4) = -18
point[2] = (4,5) edge[2]: (1-4)(5+5) = -30
point[3] = (1,5) edge[3]: (1-1)(0+5) = 0
point[4] = (1,0) edge[4]: (5-1)(0+0) = 0
...
Selecting a row of pandas series/dataframe by integer index
...
echoing @HYRY, see the new docs in 0.11
http://pandas.pydata.org/pandas-docs/stable/indexing.html
Here we have new operators, .iloc to explicity support only integer indexing, and .loc to explicity support only label indexing
e.g. imagine this scenario
In ...
How to position a DIV in a specific coordinates?
...
answered Jul 23 '11 at 20:01
Michael BerkowskiMichael Berkowski
246k3636 gold badges408408 silver badges359359 bronze badges
...
Can someone explain this 'double negative' trick? [duplicate]
...ue.
The "falsey" values are:
false
NaN
undefined
null
"" (empty string)
0
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