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Minimizing NExpectation for a custom distribution in Mathematica
...a minimum requires either to set the first derivative of the function zero and solve for a solution. Since your function is quite complicated (and probably not differentiable), the second possibility is to do a numerical minimization, which requires many evaluations of your function. Ergo, it is ver...
Detecting a mobile browser
...m detectmobilebrowsers.com):
Here's a function that uses an insanely long and comprehensive regex which returns a true or false value depending on whether or not the user is browsing with a mobile.
window.mobileCheck = function() {
let check = false;
(function(a){if(/(android|bb\d+|meego).+mob...
RegEx for Javascript to allow only alphanumeric
...y only works if the string is alphanumeric, meaning contains both a letter and a number. I just want one what would allow either and not require both.
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How to install Android SDK Build Tools on the command line?
I want to setup the Android dev environment from command line, and encounter the following issue:
19 Answers
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Center a position:fixed element
...a position: fixed; popup box centered to the screen with a dynamic width and height. I used margin: 5% auto; for this. Without position: fixed; it centers fine horizontally, but not vertically. After adding position: fixed; , it's even not centering horizontally.
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How do I get the full path to a Perl script that is executing?
I have Perl script and need to determine the full path and filename of the script during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't ...
Matplotlib plots: removing axis, legends and white spaces
I'm new to Python and Matplotlib, I would like to simply apply colormap to an image and write the resulting image, without using axes, labels, titles or anything usually automatically added by matplotlib. Here is what I did:
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Converting between datetime, Timestamp and datetime64
...d by np.datetime64 as time in UTC.
To convert datetime to np.datetime64 and back (numpy-1.6):
>>> np.datetime64(datetime.utcnow()).astype(datetime)
datetime.datetime(2012, 12, 4, 13, 34, 52, 827542)
It works both on a single np.datetime64 object and a numpy array of np.datetime64.
Th...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...hat the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the case in python2.7.
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