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How to match a String against string literals in Rust?
...
101
You can do something like this:
match &stringthing[..] {
"a" => println!("0"),
...
COUNT DISTINCT with CONDITIONS
...count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex, is actually the same as the first one, except that you use case...when clause. In ...
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...
Javascript How to define multiple variables on a single line?
... |
edited Nov 12 '10 at 16:39
answered Nov 12 '10 at 16:27
...
Opacity of background-color, but not the text [duplicate]
...
601
Use rgba!
.alpha60 {
/* Fallback for web browsers that don't support RGBa */
backgroun...
Clearing a string buffer/builder after loop
...ete method as follows:
StringBuffer sb = new StringBuffer();
for (int n = 0; n < 10; n++) {
sb.append("a");
// This will clear the buffer
sb.delete(0, sb.length());
}
Another option (bit cleaner) uses setLength(int len):
sb.setLength(0);
See Javadoc for more info:
...
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...
How to pass optional arguments to a method in C++?
...e of passing mode as optional parameter
void myfunc(int blah, int mode = 0)
{
if (mode == 0)
do_something();
else
do_something_else();
}
you can call myfunc in both ways and both are valid
myfunc(10); // Mode will be set to default 0
myfunc(10, 1); // Mode will be ...
Zooming MKMapView to fit annotation pins?
...MKMapView and have added a number of annotation pins to the map about a 5-10 kilometre area. When I run the application my map starts zoomed out to show the whole world, what is the best way to zoom the map so the pins fit the view?
...
What is the difference between & and && in Java?
...the first operand evaluates to false since the result will be false
(x != 0) & (1/x > 1) <-- this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an exception.
(x != 0) && (1/x > 1) <-- this means evaluate (x...