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Remove duplicated rows using dplyr
...ow:
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 frame [...
Measure execution time for a Java method [duplicate]
...
answered Aug 1 '10 at 17:38
Vitalii FedorenkoVitalii Fedorenko
91.6k2424 gold badges140140 silver badges111111 bronze badges
...
Scala: List[Future] to Future[List] disregarding failed futures
...equence(...) but there's a twist... The list I'm given usually has around 10-20 futures in it, and it's not uncommon for one of those futures to fail (they are making external web service requests). Instead of having to retry all of them in the event that one of them fails, I'd like to be able to g...
Multiline bash commands in makefile
...
answered Apr 12 '12 at 10:13
Eldar AbusalimovEldar Abusalimov
20k44 gold badges5656 silver badges6565 bronze badges
...
Check if option is selected with jQuery, if not select a default
...ures in Firebug.
– semperos
Aug 12 '10 at 21:08
28
As of jQuery 1.6 you can set the property dire...
What is the proper way to test if a parameter is empty in a batch file?
...
answered Mar 29 '10 at 22:56
Dan StoryDan Story
9,01011 gold badge2020 silver badges2727 bronze badges
...
Sequence contains no matching element
...
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edited Oct 22 '10 at 6:22
answered Oct 22 '10 at 6:14
...
Why doesn't Ruby support i++ or i-- (increment/decrement operators)?
...t in an old thread:
Hi,
In message "[ruby-talk:02706] X++?"
on 00/05/10, Aleksi Niemelä <aleksi.niemela@cinnober.com> writes:
|I got an idea from http://www.pragprog.com:8080/rubyfaq/rubyfaq-5.html#ss5.3
|and thought to try. I didn't manage to make "auto(in|de)crement" working so
|coul...
How to update SQLAlchemy row entry?
...hanks!
– Hatshepsut
Mar 1 '17 at 20:10
1
@Hatshepsut One difference that I came across today betw...
Why does changing 0.1f to 0 slow down performance by 10x?
...trap and resolve them using microcode.
If you print out the numbers after 10,000 iterations, you will see that they have converged to different values depending on whether 0 or 0.1 is used.
Here's the test code compiled on x64:
int main() {
double start = omp_get_wtime();
const float x[...