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In Python, what is the difference between “.append()” and “+= []”?
...ase the only difference is performance: append is twice as fast.
Python 3.0 (r30:67507, Dec 3 2008, 20:14:27) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import timeit
>>> timeit.Timer('s.append("something")', 's...
How do I break out of nested loops in Java?
...ic static void main(String[] args) {
outerloop:
for (int i=0; i < 5; i++) {
for (int j=0; j < 5; j++) {
if (i * j > 6) {
System.out.println("Breaking");
break outerloop;
}
Sys...
Opacity of background-color, but not the text [duplicate]
...
601
Use rgba!
.alpha60 {
/* Fallback for web browsers that don't support RGBa */
backgroun...
How might I convert a double to the nearest integer value?
...
answered Mar 11 '09 at 4:33
nickfnickf
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...
how to check redis instance version?
...
310
$ redis-server --version
gives you the version.
...
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...
UITextfield leftView/rightView padding on iOS7
...
90
Was just working on this myself and used this solution:
- (CGRect) rightViewRectForBounds:(CGRe...
Maximum single-sell profit
...ry!), but it's helpful to see the algorithm evolve:
5 10 4 6 7
min 5 5 4 4 4
best (5,5) (5,10) (5,10) (5,10) (5,10)
Answer: (5, 10)
5 10 4 6 12
min ...
How to style dt and dd so they are on the same line?
...
dl {
width: 100%;
overflow: hidden;
background: #ff0;
padding: 0;
margin: 0
}
dt {
float: left;
width: 50%;
/* adjust the width; make sure the total of both is 100% */
background: #cc0;
padding: 0;
margin: ...