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Is object empty? [duplicate]
...th: 0, custom_property: []}), // true
isEmpty("Hello"), // false
isEmpty([1,2,3]), // false
isEmpty({test: 1}), // false
isEmpty({length: 3, custom_property: [1,2,3]}) // false
If you only need to handle ECMAScript5 browsers, you can use Object.getOwnPropertyNames instead of the hasOwnProperty lo...
Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...umns to DataFrame constructor, as in:
>>> pd.DataFrame(data=data[1:,1:], # values
... index=data[1:,0], # 1st column as index
... columns=data[0,1:]) # 1st row as the column names
edit: as in the @joris comment, you may need to change above to np.int_(dat...
How to check if a string is a valid hex color representation?
...d support for 3-character HEX codes, use the following:
/^#([0-9A-F]{3}){1,2}$/i.test('#ABC')
The only difference here is that
[0-9A-F]{6}
is replaced with
([0-9A-F]{3}){1,2}
This means that instead of matching exactly 6 characters, it will match exactly 3 characters, but 1 or 2 times. Al...
How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...e number must be converted to a string:
require 'date'
DateTime.strptime("1318996912",'%s')
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
My current version of ruby is ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.5.0] but I want to update it to the latest patch level using rvm. How can I do this?
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How to calculate the angle between a line and the horizontal axis?
...xtend infinitely and don't start at a particular point).
deltaY = P2_y - P1_y
deltaX = P2_x - P1_x
Then calculate the angle (which runs from the positive X axis at P1 to the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividin...
How to drop a list of rows from Pandas dataframe?
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Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
I have a computer with 1 MB of RAM and no other local storage. I must use it to accept 1 million 8-digit decimal numbers over a TCP connection, sort them, and then send the sorted list out over another TCP connection.
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Generating random whole numbers in JavaScript in a specific range?
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How to validate an email address in PHP
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