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TypeScript: casting HTMLElement
...var script = <HTMLScriptElement>document.getElementsByName("script")[0];
However, unfortunately you cannot do:
var script = (<HTMLScriptElement[]>document.getElementsByName(id))[0];
You get the error
Cannot convert 'NodeList' to 'HTMLScriptElement[]'
But you can do :
(<HTMLS...
Replace a value if null or undefined in JavaScript
...
Here’s the JavaScript equivalent:
var i = null;
var j = i || 10; //j is now 10
Note that the logical operator || does not return a boolean value but the first value that can be converted to true.
Additionally use an array of objects instead of one single object:
var options = {
...
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...
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
share
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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...
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...
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 ...
Declaring variables inside or outside of a loop
...
20 Answers
20
Active
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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...
php中json_decode()和json_encode()的使用方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...de()和json_encode()的使用方法1.json_decode()json_decode(PHP 5 >= 5.2.0, PECL json >= 1.2.0)json_decode — 对 JSON 格式的字符串进行编码说明mixed jso...1.json_decode()
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
对 JSON 格式的字符串进行编码
说明：
mixed json_decode ...