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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 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 position a DIV in a specific coordinates?
...
answered Jul 23 '11 at 20:01
Michael BerkowskiMichael Berkowski
246k3636 gold badges408408 silver badges359359 bronze badges
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Flexbox and Internet Explorer 11 (display:flex in ?)
...
According to http://caniuse.com/#feat=flexbox:
"IE10 and IE11 default values for flex are 0 0 auto rather than 0 1 auto, as per the draft spec, as of September 2013"
So in plain words, if somewhere in your CSS you have something like this: flex:1 , that is not translated the...
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 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...
Default value to a parameter while passing by reference in C++
...
104
You can do it for a const reference, but not for a non-const one. This is because C++ does not ...
How would I extract a single file (or changes to a file) from a git stash?
...D when the
stash was created.
So you can treat stash (e.g. stash@{0} is first / topmost stash) as a merge commit, and use:
$ git diff stash@{0}^1 stash@{0} -- <filename>
Explanation: stash@{0}^1 means the first parent of the given stash, which as stated in the explanation above is ...