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Is it better to use std::memcpy() or std::copy() in terms to performance?
... 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the memcpy version and the std::copy version. My code takes adv...
C# Error: Parent does not contain a constructor that takes 0 arguments
...
203
Since you don't explicitly invoke a parent constructor as part of your child class constructor,...
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 match a String against string literals in Rust?
...
101
You can do something like this:
match &stringthing[..] {
"a" => println!("0"),
...
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: ...
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...
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...
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.
...