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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...
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 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
...
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 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 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
...
Can someone explain this 'double negative' trick? [duplicate]
...ue.
The "falsey" values are:
false
NaN
undefined
null
"" (empty string)
0
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How to position a DIV in a specific coordinates?
...
answered Jul 23 '11 at 20:01
Michael BerkowskiMichael Berkowski
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How to calculate cumulative normal distribution?
...le:
>>> from scipy.stats import norm
>>> norm.cdf(1.96)
0.9750021048517795
>>> norm.cdf(-1.96)
0.024997895148220435
In other words, approximately 95% of the standard normal interval lies within two standard deviations, centered on a standard mean of zero.
If you need t...