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In Python, how do I convert all of the items in a list to floats?
...
470
[float(i) for i in lst]
to be precise, it creates a new list with float values. Unlike the map...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
...here):
unsigned int
reverse(register unsigned int x)
{
x = (((x & 0xaaaaaaaa) >> 1) | ((x & 0x55555555) << 1));
x = (((x & 0xcccccccc) >> 2) | ((x & 0x33333333) << 2));
x = (((x & 0xf0f0f0f0) >> 4) | ((x & 0x0f0f0f0f) << 4));
...
Sample random rows in dataframe
...
460
First make some data:
> df = data.frame(matrix(rnorm(20), nrow=10))
> df
X1 ...
How do I get bit-by-bit data from an integer value in C?
...wanted){
int *bits = malloc(sizeof(int) * bitswanted);
int k;
for(k=0; k<bitswanted; k++){
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
bits[k] = thebit;
}
return bits;
}
int main(){
int n=7;
int bitswanted = 5;
int...
Canvas width and height in HTML5
...
390
The canvas DOM element has .height and .width properties that correspond to the height="…" and...
How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?
...ystem should contain plenty information for your quest. My system (2.6.32-40-generic #87-Ubuntu) suggests:
/sys/class/tty
Which gives you descriptions of all TTY devices known to the system. A trimmed down example:
# ll /sys/class/tty/ttyUSB*
lrwxrwxrwx 1 root root 0 2012-03-28 20:43 /sys/class/...
How to truncate the time on a DateTime object in Python?
...
390
I think this is what you're looking for...
>>> import datetime
>>> dt = datet...
Pandas groupby: How to get a union of strings
..._csv(StringIO(data),sep='\s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When...
Is it correct to use JavaScript Array.sort() method for shuffling?
...
110
It's never been my favourite way of shuffling, partly because it is implementation-specific as y...
how to use sed, awk, or gawk to print only what is matched?
... tried * instead and I added p tag for printing match:
sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt
For matching at least one numeric character without +, I would use:
sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\1/p' example.txt
...