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Immutable vs Mutable types
...
What? Floats are immutable? But can't I do
x = 5.0
x += 7.0
print x # 12.0
Doesn't that "mut" x?
Well you agree strings are immutable right? But you can do the same thing.
s = 'foo'
s += 'bar'
print s # foobar
The value of the variable changes, but it changes by chang...
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: ...
byte[] to hex string [duplicate]
...
605
There is a built in method for this:
byte[] data = { 1, 2, 4, 8, 16, 32 };
string hex = BitCo...
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...
python plot normal distribution
...ot as plt
import numpy as np
import scipy.stats as stats
import math
mu = 0
variance = 1
sigma = math.sqrt(variance)
x = np.linspace(mu - 3*sigma, mu + 3*sigma, 100)
plt.plot(x, stats.norm.pdf(x, mu, sigma))
plt.show()
s...
How to get datetime in JavaScript?
How to get date time in JavaScript with format 31/12/2010 03:55 AM?
7 Answers
7
...
how to check redis instance version?
...
310
$ redis-server --version
gives you the version.
...
How accurately should I store latitude and longitude?
...tor
decimal degrees distance
places
-------------------------------
0 1.0 111 km
1 0.1 11.1 km
2 0.01 1.11 km
3 0.001 111 m
4 0.0001 11.1 m
5 0.00001 1.11 m
6 0.000001 0.111 m
7 0.0000001 1.11 cm
8 ...
ReactJS: Modeling Bi-Directional Infinite Scrolling
...render them, it's really cheap to just allocate them and discard them. If 10k allocations is too big, you can instead pass a function that takes a range and return the elements.
<List>
{thousandelements.map(function() { return <Element /> })}
</List>
Your List component is kee...
What's the UIScrollView contentInset property for?
...enclosing scroll view.
Obj-C
aScrollView.contentInset = UIEdgeInsetsMake(0, 0, 0, 7.0);
Swift 5.0
aScrollView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 7.0)
Here's a good iOS Reference Library article on scroll views that has an informative screenshot (fig 1-3) - I'll rep...