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Convert columns to string in Pandas
...cated dtype.
object dtype breaks dtype-specific operations like DataFrame.select_dtypes(). There isn’t a clear way to select just text
while excluding non-text but still object-dtype columns.
When reading code, the contents of an object dtype array is less clear than 'string'.
See also the se...
How to change the name of the active scheme in Xcode?
...t Scheme" from the "Product" menu.
Click on the "Manage Schemes…" button
Select the scheme whose name you wish to change
Press the "Return" key
It will select the name of the scheme and allow you to edit it.
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...
Compare two objects' properties to find differences?
...pe t1, Type t2) {
var list1 = t1.GetProperties().OrderBy(x => x.Name).Select(x => x.Name);
var list2 = t2.GetProperties().OrderBy(x => x.Name).Select(x => x.Name);
return list1.SequenceEqual(list2);
}
shar...
How do I install a NuGet package into the second project in a solution?
...
The selected one in the dropdown
– davidfowl
Aug 31 '15 at 16:39
...
jQuery: fire click() before blur() event
...opdown from stealing focus. The slight advantage is that the value will be selected when the mouse button is released, which is how native select components work. JSFiddle
$('input').on('focus', function() {
$('ul').show();
}).on('blur', function() {
$('ul').hide();
});
$('ul').on('mousedo...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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How to combine two or more querysets in a Django view?
...s. For example:
>>> qs1.union(qs2, qs3)
The UNION operator selects only distinct values by default. To allow duplicate values, use the all=True
argument.
union(), intersection(), and difference() return model instances of
the type of the first QuerySet even if the arguments ...
WAMP shows error 'MSVCR100.dll' is missing when install
...s://www.microsoft.com/en-us/download/details.aspx?id=30679
There you can select the x86 or x64 version depending on your system
This article on the WampServer forums shows all the Microsoft Visual C++ runtime libraries you need to have installed on your system for each version of WampServer. To ...
How can I calculate the number of lines changed between two commits in git?
...2>
but you can use --numstat or --shortstat as well. git log can also select commits in a variety other ways - have a look at the documentation. You might be interested in things like --since (rather than specifying commit ranges, just select commits since last week) and --no-merges (merge comm...
How can I define a composite primary key in SQL?
...for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from th...