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javascript set a variable if undefined
...efined. It would therefore not only match undefined but also null, false, 0, NaN, "" (but not "0").
If you want to set to default only if the variable is strictly undefined then the safest way is to write:
var x = (typeof x === 'undefined') ? your_default_value : x;
On newer browsers it's actu...
Format decimal for percentage values?
...se the P format string. This will vary by culture:
String.Format("Value: {0:P2}.", 0.8526) // formats as 85.26 % (varies by culture)
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Is there a way to 'uniq' by column?
... delimiter
-k1,1 for the key field 1
Test result:
overflow@domain2.com,2009-11-27 00:58:29.793000000,xx3.net,255.255.255.0
stack2@domain.com,2009-11-27 01:05:47.893000000,xx2.net,127.0.0.1
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How to calculate a logistic sigmoid function in Python?
... math.exp(-x))
And now you can test it by calling:
>>> sigmoid(0.458)
0.61253961344091512
Update: Note that the above was mainly intended as a straight one-to-one translation of the given expression into Python code. It is not tested or known to be a numerically sound implementation. I...
How do I upload a file with metadata using a REST web service?
...": 52.12873
}
To create the metadata entry and return a response like:
201 Created
Location: http://server/data/media/21323
{
"Name": "Test",
"Latitude": 12.59817,
"Longitude": 52.12873,
"ContentUrl": "http://server/data/media/21323/content"
}
The client can then use this Conten...
Declaring variables inside or outside of a loop
...
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Clear icon inside input text
...ch" to your input
The support is pretty decent but will not work in IE<10
<input type="search">
Clearable input for old browsers
If you need IE9 support here are some workarounds
Using a standard <input type="text"> and some HTML elements:
/**
* Clearable text ...
Numpy how to iterate over columns of array?
...
– Ibrahim Muhammad
Sep 23 '13 at 17:08
49
For those wondering, array.T isn't costly, as it just c...
How do I calculate a point on a circle’s circumference?
...
600
The parametric equation for a circle is
x = cx + r * cos(a)
y = cy + r * sin(a)
Where r is t...
How can I convert an RGB image into grayscale in Python?
...
320
How about doing it with Pillow:
from PIL import Image
img = Image.open('image.png').convert('LA...