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Transpose/Unzip Function (inverse of zip)?
...
802
zip is its own inverse! Provided you use the special * operator.
>>> zip(*[('a', 1), ...
Random Gaussian Variables
...rand = new Random(); //reuse this if you are generating many
double u1 = 1.0-rand.NextDouble(); //uniform(0,1] random doubles
double u2 = 1.0-rand.NextDouble();
double randStdNormal = Math.Sqrt(-2.0 * Math.Log(u1)) *
Math.Sin(2.0 * Math.PI * u2); //random normal(0,1)
double randNormal =...
Set time to 00:00:00
...oblem resetting hours in Java. For a given date I want to set the hours to 00:00:00.
12 Answers
...
Breadth First Vs Depth First
...|
edited Feb 12 '12 at 21:05
answered Mar 26 '09 at 22:08
d...
How to use QueryPerformanceCounter?
...
#include <windows.h>
double PCFreq = 0.0;
__int64 CounterStart = 0;
void StartCounter()
{
LARGE_INTEGER li;
if(!QueryPerformanceFrequency(&li))
cout << "QueryPerformanceFrequency failed!\n";
PCFreq = double(li.QuadPart)/1000.0;
Q...
How to find the length of a string in R
...
See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sample(LETTERS, 10), collapse = "")
> strn
[1] "NHKPBEFTLY"
> nchar(strn)
[1] 10
share
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im...
How can I filter lines on load in Pandas read_csv function?
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170
There isn't an option to filter the rows before the CSV file is loaded into a pandas object.
Y...
How to create file execute mode permissions in Git on Windows?
...Temp\TestRepo>git add foo.sh
C:\Temp\TestRepo>git ls-files --stage
100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0 foo.sh
As you note, after adding, the mode is 0644 (ie, not executable). However, we can mark it as executable before committing:
C:\Temp\TestRepo>git update-index...
In Hibernate Validator 4.1+, what is the difference between @NotNull, @NotEmpty, and @NotBlank?
...he CharSequence, Collection, Map or Array object is not null and size > 0.
@NotBlank: The string is not null and the trimmed length is greater than zero.
To help you understand, let's look into how these constraints are defined and carried out (I'm using version 4.1):
The @NotNull constrain...
get list from pandas dataframe column
..._one_arr}\ntype:{type(col_one_arr)}")
Output:
DataFrame:
one two
a 1.0 1
b 2.0 2
c 3.0 3
d NaN 4
column types:
one float64
two int64
dtype: object
col_one_list:
[1.0, 2.0, 3.0, nan]
type:<class 'list'>
col_one_arr:
[ 1. 2. 3. nan]
type:<class 'numpy.ndarray...