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Replace None with NaN in pandas dataframe
...beware when you run df.replace([None], np.nan, inplace=True), this changed all datetime objects with missing data to object dtypes. So now you may have broken queries unless you change them back to datetime which can be taxing depending on the size of your data.
– Doubledown
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Changing user agent on urllib2.urlopen
...eaders should be a dictionary, and will be treated as if add_header() was called with each key and value as arguments. This is often used to “spoof” the User-Agent header, which is used by a browser to identify itself – some HTTP servers only allow requests coming from common browsers as oppos...
Finding the PHP File (at run time) where a Class was Defined
...rejected? " I realize I could use (get_included_files()) to get a list of all the files that have been included so far and then parse them all manually, but that's a lot of file system access for a single attempt."
– Alan Storm
Mar 10 '10 at 20:22
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What is the difference between varchar and nvarchar?
... nvarchar supports multibyte characters? If that is the case, is there really any point, other than storage concerns, to using varchars ?
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MySQL: Can't create table (errno: 150)
... child table InnoDB engine. Current create.sql script was using InnoDB for all tables, but I had very very old installation where first script used MyISAM.
– Whome
Apr 8 '13 at 9:50
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How can I get the corresponding table header (th) from a table cell (td)?
...$(function($) {
"use strict";
// Only part of the demo, the thFromTd call does the work
$(document).on('mouseover mouseout', 'td', function(event) {
var td = $(event.target).closest('td'),
th = thFromTd(td);
th.parent().find('.highlight').removeClass('highlight');
if (even...
Why is MATLAB so fast in matrix multiplication?
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Here's my results using MATLAB R2011a + Parallel Computing Toolbox on a machine with a Tesla C2070:
>> A = rand(1024); gA = gpuArray(A);
% warm up by executing the operations a couple of times, and then:
>> tic, C = A * A; toc
Elapsed time is 0.075396 sec...
seek() function?
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Regarding seek() there's not too much to worry about.
First of all, it is useful when operating over an open file.
It's important to note that its syntax is as follows:
fp.seek(offset, from_what)
where fp is the file pointer you're working with; offset means how many positions you wi...
Why would you use String.Equals over ==? [duplicate]
I recently was introduced to a large codebase and noticed all string comparisons are done using String.Equals() instead of ==
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Get cookie by name
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@user3132564 tried to edit this in, but its actually a comment: This method returns the wrong value when you search for a suffix of a cookie - if the value of document.cookie is "FirstName=John" and you call getCookie("Name"), you'll get back "John" even though there's no ...