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Can someone explain the dollar sign in Javascript?
...s that contain a jQuery object with a $ so that they are easily identified and not mixed up with, say, integers.
The dollar sign function $() in jQuery is a library function that is frequently used, so a short name is desirable.
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How to implement a binary tree?
... if val == node.v:
return node
elif (val < node.v and node.l is not None):
self._find(val, node.l)
elif (val > node.v and node.r is not None):
self._find(val, node.r)
def deleteTree(self):
# garbage collector will do this for u...
why is plotting with Matplotlib so slow?
...ating different python plotting libraries. Right now I'm trying matplotlib and I'm quite disappointed with the performance. The following example is modified from SciPy examples and gives me only ~ 8 frames per second!
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How can I check if a command exists in a shell script? [duplicate]
...my first shell script. In my script I would like to check if a certain command exists, and if not, install the executable. How would I check if this command exists?
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Can't connect to MySQL server error 111 [closed]
...ut when i try to connect to this IP it alway error(111). but use localhost and 127.0.0.1 is OK.
4 Answers
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How do I compare two DateTime objects in PHP 5.2.8?
... Thanks Milen, looks like I just needed my false assumptions removed and suddenly the glaring bug in my code became obvious to me.
– RedBlueThing
Jun 7 '09 at 5:26
2
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Determine which element the mouse pointer is on top of in JavaScript
...ntFromPoint which does what it sounds like.
What we need is to find the x and y coords of the mouse and then call it using those values:
var x = event.clientX, y = event.clientY,
elementMouseIsOver = document.elementFromPoint(x, y);
document.elementFromPoint
jQuery event object
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How to write a switch statement in Ruby
...Ruby uses the case expression instead.
case x
when 1..5
"It's between 1 and 5"
when 6
"It's 6"
when "foo", "bar"
"It's either foo or bar"
when String
"You passed a string"
else
"You gave me #{x} -- I have no idea what to do with that."
end
Ruby compares the object in the when clause wit...
Alphabet range in Python
...', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>>> list(map(chr, range(97, 123))) #or list(map(chr, range(ord('a'), ord('z')+1)))
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v...
How do I invert BooleanToVisibilityConverter?
...s fine, but I'd like one of the controls to hide if the boolean is true , and show if it's false .
17 Answers
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