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How to add a new row to an empty numpy array
...
The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...
Best way of returning a random boolean value
...alse].sample is faster than rand(2) == 1. When I performed each operation 10 million times the rand method was 2.179s. The sample method was 1.645s.
– Mirror318
Jun 27 '16 at 4:47
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c# datatable insert column at position 0
...oes anyone know the best way to insert a column in a datatable at position 0?
3 Answers
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Remove trailing zeros
...this, if the input IS a string? You can use one of these:
string.Format("{0:G29}", decimal.Parse("2.0044"))
decimal.Parse("2.0044").ToString("G29")
2.0m.ToString("G29")
This should work for all input.
Update Check out the Standard Numeric Formats I've had to explicitly set the precision specif...
How is Math.Pow() implemented in .NET Framework?
...king for an efficient approach for calculating a b (say a = 2 and b = 50 ). To start things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
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Difference between DateTime and Time in Ruby
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Newer versions of Ruby (2.0+) do not really have significant differences between the two classes. Some libraries will use one or the other for historical reasons, but new code does not necessarily need to be concerned. Picking one for consistency is p...
CSS Box Shadow - Top and Bottom Only [duplicate]
...operty can accept a comma-separated list of shadows like this:
box-shadow: 0px 10px 5px #888, 0px -10px 5px #888;
This will give you some control over the "amount" of shadow in each direction.
Have a look at http://www.css3.info/preview/box-shadow/ for more information about box-shadow.
Hope this w...
Deleting an element from an array in PHP
...t() which will convert all keys to numerical enumerated keys starting from 0.
Code
<?php
$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
//↑ Key which you want to delete
?>
Output
[
[0] => a
[2] => c
]
\array_splice() method
If yo...
How can I access my localhost from my Android device?
...ble to access my laptop web server using the Android emulator, I'm using 10.0.2.2:portno
works well.
39 Answers
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How do you convert epoch time in C#?
...ou convert Unix epoch time into real time in C#? (Epoch beginning 1/1/1970)
14 Answers
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