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Cannot ping AWS EC2 instance
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answered May 30 '15 at 9:39
RakibRakib
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Getting the array length of a 2D array in Java
... };
System.out.println(foo.length); //2
System.out.println(foo[0].length); //3
System.out.println(foo[1].length); //4
}
Column lengths differ per row. If you're backing some data by a fixed size 2D array, then provide getters to the fixed values in a wrapper class.
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Add column with constant value to pandas dataframe [duplicate]
...numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = df.a[:5]
In [12]: dfa, sa = df.align(s, axis=0)
In [13]: dfa
Out[13]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 ...
How to make good reproducible pandas examples
...nd below your code with your code unindented:
In [2]: df
Out[2]:
A B
0 1 2
1 1 3
2 4 6
test pd.read_clipboard(sep='\s\s+') yourself.
* I really do mean small, the vast majority of example DataFrames could be fewer than 6 rowscitation needed, and I bet I can do it in 5 rows. Can you re...
How to format a number as percentage in R?
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10 Answers
10
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Why does changing 0.1f to 0 slow down performance by 10x?
...rap and resolve them using microcode.
If you print out the numbers after 10,000 iterations, you will see that they have converged to different values depending on whether 0 or 0.1 is used.
Here's the test code compiled on x64:
int main() {
double start = omp_get_wtime();
const float x[1...
Finding current executable's path without /proc/self/exe
...ross-platform interfaces. I've seen some projects mucking around with argv[0], but it doesn't seem entirely reliable.
13 A...
C# Regex for Guid
... you say.
resultString = Regex.Replace(subjectString,
@"(?im)^[{(]?[0-9A-F]{8}[-]?(?:[0-9A-F]{4}[-]?){3}[0-9A-F]{12}[)}]?$",
"'$0'");
This matches the following styles, which are all equivalent and acceptable formats for a GUID.
ca761232ed4211cebacd00aa0057b223
CA761232-ED42-11CE-BAC...
Syntax for creating a two-dimensional array
...
Try the following:
int[][] multi = new int[5][10];
... which is a short hand for something like this:
int[][] multi = new int[5][];
multi[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every...
Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...