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Why does Math.round(0.49999999999999994) return 1?
...n see that each value slightly less than .5 is rounded down, except for 0.5 .
5 Answers
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In php, is 0 treated as empty?
...ollowing things are considered to be empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (an empty array)
var $var; (a variable declared, but without a value in a class)
Note that this is exactly the same list as for a ...
remove None value from a list without removing the 0 value
...
10 Answers
10
Active
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计算统计特征（正态分布）函数及实例 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ain(int argc, _TCHAR* argv[])
{
std::map<int, int> map_test;
map_test[0] = 100;
map_test[5] = 80;
map_test[2] = 10;
map_test[8] = 99;
map_test[4] = 102;
StdevInfo stdev_info;
stdev_info.init();
stdev_info.caculate_stdev_info(map_test.begin(), map_test.end(),
[](const std::p...
What does {0} mean when initializing an object?
When {0} is used to initialize an object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
...
How to draw a rounded Rectangle on HTML Canvas?
...
50
The HTML5 canvas doesn't provide a method to draw a rectangle with rounded corners.
How about u...
MySQL ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)
...
You probably have an anonymous user ''@'localhost' or ''@'127.0.0.1'.
As per the manual:
When multiple matches are possible, the server must determine which of
them to use. It resolves this issue as follows: (...)
When a client attempts to connect, the server looks throug...
How do I print a double value without scientific notation using Java?
...8;
System.out.printf("dexp: %f\n", dexp);
This will print dexp: 12345678.000000. If you don't want the fractional part, use
System.out.printf("dexp: %.0f\n", dexp);
This uses the format specifier language explained in the documentation.
The default toString() format used in your original code ...
How do I create an empty array/matrix in NumPy?
...rt numpy
>>> a = numpy.zeros(shape=(5,2))
>>> a
array([[ 0., 0.],
[ 0., 0.],
[ 0., 0.],
[ 0., 0.],
[ 0., 0.]])
>>> a[0] = [1,2]
>>> a[1] = [2,3]
>>> a
array([[ 1., 2.],
[ 2., 3.],
[ 0., 0.],
[ 0., 0.],
[ 0., 0.]])
...
How can I do DNS lookups in Python, including referring to /etc/hosts?
...
Justin M. Keyes
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answered May 10 '10 at 18:36
Jochen RitzelJochen R...