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Drop unused factor levels in a subsetted data frame
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Also: this method does preserve the ordering of the variable.
– webelo
Jul 1 '16 at 0:36
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LINQ OrderBy versus ThenBy
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You should definitely use ThenBy rather than multiple OrderBy calls.
I would suggest this:
tmp = invoices.InvoiceCollection
.OrderBy(o => o.InvoiceOwner.LastName)
.ThenBy(o => o.InvoiceOwner.FirstName)
.ThenBy(o => o.InvoiceID...
MIN and MAX in C
Where are MIN and MAX defined in C, if at all?
14 Answers
14
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How to replace multiple substrings of a string?
...eplaced with items()
Careful: Python dictionaries don't have a reliable order for iteration. This solution only solves your problem if:
order of replacements is irrelevant
it's ok for a replacement to change the results of previous replacements
For instance:
d = { "cat": "dog", "dog": "pig"...
What is a “Bitmap heap scan” in a query plan?
... is different from an index scan, where the index is visited row by row in order -- meaning a disk page may get visited multiple times.
Re: the question in your comment... Yep, that's exactly it.
An index scan will go through rows one by one, opening disk pages again and again, as many times as ...
Unable to update the EntitySet - because it has a DefiningQuery and no element exis
...really weird issue. Is there any information on how this problem occurs in order to avoid it? Nonetheless - it helped
– r3dst0rm
Jan 24 '18 at 9:56
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How should I log while using multiprocessing in Python?
...that its log goes to a different file descriptor (to disk or to pipe.) Ideally, all log entries should be timestamped.
Your controller process can then do one of the following:
If using disk files: Coalesce the log files at the end of the run, sorted by timestamp
If using pipes (recommended): C...
Sorting arrays in NumPy by column
... actually the most elegant way of doing it.
For the "correct" way see the order keyword argument of numpy.ndarray.sort
However, you'll need to view your array as an array with fields (a structured array).
The "correct" way is quite ugly if you didn't initially define your array with fields...
A...
How can I add reflection to a C++ application?
...rate the data about each field(plus the field itself). This macro will be called like this:
REFLECTABLE
(
(const char *) name,
(int) age
)
So using Boost.PP we iterate over each argument and generate the data like this:
// A helper metafunction for adding const to a type
template<clas...
Check if OneToOneField is None in Django
... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...