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How to draw polygons on an HTML5 canvas?
...dle top of the polygon rather than the middle right, flip the sin and cos calls and change Ycenter + to Ycenter - on both places (leaving it as a sum rather than a difference of the values results in it starting with a point at the bottom of the resultant shape). I am not a clever man when it comes...
Subtract days from a date in JavaScript
...t saving time is only 23 hours long, and the last is 25 hours long. it usually doesn't matter, but it's something to consider.
– Kip
Aug 18 '09 at 20:55
12
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Stop/Close webcam which is opened by navigator.getUserMedia
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EDIT
Since this answer has been originally posted the browser API has changed.
.stop() is no longer available on the stream that gets passed to the callback.
The developer will have to access the tracks that make up the stream (audio or video) and stop each of th...
What's the difference between '$(this)' and 'this'?
... help to do DOM things just keep this in mind.
$(this)[0] === this
Basically every time you get a set of elements back jQuery turns it into a jQuery object. If you know you only have one result, it's going to be in the first element.
$("#myDiv")[0] === document.getElementById("myDiv");
And so ...
Apply pandas function to column to create multiple new columns?
...
I usually do this using zip:
>>> df = pd.DataFrame([[i] for i in range(10)], columns=['num'])
>>> df
num
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
>>> def powers(x):
>...
What is the explanation for these bizarre JavaScript behaviours mentioned in the 'Wat' talk for Code
The 'Wat' talk for CodeMash 2012 basically points out a few bizarre quirks with Ruby and JavaScript.
5 Answers
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Building big, immutable objects without using constructors having long parameter lists
...of course completely wrong.
The trick is that only the build() method actually creates a Foo (hence you Foo can be immutable).
FooFactory.create(), whereXXX(..) and withXXX(..) all create "something else".
That something else may be a FooFactory, here's one way to do it....
You FooFactory would ...
How to make a always full screen?
...
This is the most stable (and easy) way to do it, and it works in all modern browsers:
.fullscreen {
position: fixed;
top: 0;
left: 0;
bottom: 0;
right: 0;
overflow: auto;
background: lime; /* Just to visualize the extent */
}
<div class="fullscreen">
...
Convert Pandas column containing NaNs to dtype `int`
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@jsc123 you can use the object dtype. This comes with a small health warning but for the most part works well.
– Andy Hayden
May 19 '15 at 15:16
1
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JavaScript before leaving the page
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Just a note, if you want to conditionally display a message in onbeforeunload, return false will make the browser show "false" in a dialog. You need to return undefined if you want to let the window close with no user alert.
– Dan Fitch
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