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Which is faster in Python: x**.5 or math.sqrt(x)?
...
math.sqrt(x) is significantly faster than x**0.5.
import math
N = 1000000
%%timeit
for i in range(N):
z=i**.5
10 loops, best of 3: 156 ms per loop
%%timeit
for i in range(N):
z=math.sqrt(i)
10 loops, best of 3: 91.1 ms per loop
Using Python 3.6....
What is the easiest way to push an element to the beginning of the array?
...
390
What about using the unshift method?
ary.unshift(obj, ...) → ary
Prepends objects to the...
Get last n lines of a file, similar to tail
... till it's found the right number of '\n' characters.
def tail( f, lines=20 ):
total_lines_wanted = lines
BLOCK_SIZE = 1024
f.seek(0, 2)
block_end_byte = f.tell()
lines_to_go = total_lines_wanted
block_number = -1
blocks = [] # blocks of size BLOCK_SIZE, in reverse orde...
How to open, read, and write from serial port in C?
...ity)
{
struct termios tty;
if (tcgetattr (fd, &tty) != 0)
{
error_message ("error %d from tcgetattr", errno);
return -1;
}
cfsetospeed (&tty, speed);
cfsetispeed (&tty, speed);
tty.c_cflag = (tty.c_...
How to get complete address from latitude and longitude?
...
520
Geocoder geocoder;
List<Address> addresses;
geocoder = new Geocoder(this, Locale.getDefaul...
What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...
Java regex capturing groups indexes
... e.g. (\.\w+)+, or to specify where alternation should take effect, e.g. ^(0*1|1*0)$ (^, then 0*1 or 1*0, then $) versus ^0*1|1*0$ (^0*1 or 1*0$).
A capturing group, apart from grouping, will also record the text matched by the pattern inside the capturing group (pattern). Using your example, (.*):...
What is “entropy and information gain”?
...
1051
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imag...
Remove outline from select box in FF
...he color of the dotted border. So say if you do...
select {
color: rgba(0,0,0,0);
}
Firefox will render the dotted border transparent. But of course your text will be transparent too! So we must somehow display the text. text-shadow comes to the rescue:
select {
color: rgba(0,0,0,0);
text-...