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Using only CSS, show div on hover over
...ibling selector, and is the basis of the suckerfish dropdown menu.
HTML5 allows anchor elements to wrap almost anything, so in that case the div element can be made a child of the anchor. Otherwise the principle is the same - use the :hover pseudo-class to change the display property of another el...
sql ORDER BY multiple values in specific order?
...I have a table with a indexed key and a non indexed field.
I need to find all records with a certain value and return the row.
I would like to know if I can order by multiple values.
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Flask SQLAlchemy query, specify column names
... do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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What can you use Python generator functions for?
...in them. I want to know what types of problems that these functions are really good at solving.
16 Answers
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Is HttpClient safe to use concurrently?
In all the examples I can find of usages of HttpClient , it is used for one off calls. But what if I have a persistent client situation, where several requests can be made concurrently? Basically, is it safe to call client.PostAsync on 2 threads at once against the same instance of HttpClient .
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Calculate a Running Total in SQL Server
Imagine the following table (called TestTable ):
15 Answers
15
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Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...
Can you 'exit' a loop in PHP?
I have a loop that is doing some error checking in my PHP code. Originally it looked something like this...
6 Answers
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Replacing blank values (white space) with NaN in pandas
I want to find all values in a Pandas dataframe that contain whitespace (any arbitrary amount) and replace those values with NaNs.
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What is Full Text Search vs LIKE
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In general, there is a tradeoff between "precision" and "recall". High precision means that fewer irrelevant results are presented (no false positives), while high recall means that fewer relevant results are missing (no false negatives). Using the LIKE operator gives you 100% precisi...