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What does SQL clause “GROUP BY 1” mean?
Someone sent me a SQL query where the GROUP BY clause consisted of the statement: GROUP BY 1 .
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How can I wrap text to some length in Vim?
Let's speak of relative measures. My Vim looks like:
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How do I get a list of all the duplicate items using pandas in python?
I have a list of items that likely has some export issues. I would like to get a list of the duplicate items so I can manually compare them. When I try to use pandas duplicated method , it only returns the first duplicate. Is there a a way to get all of the duplicates and not just the first one?...
Aligning UIToolBar items
I have three UIBarButtonItem created as below. They align left and I'd like to align center so there isn't a gap on the right side. I don't see an align property on UIToolBar . Is there another way to accomplish this?
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How do I access named capturing groups in a .NET Regex?
I'm having a hard time finding a good resource that explains how to use Named Capturing Groups in C#. This is the code that I have so far:
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What is the fastest way to get the value of π?
I'm looking for the fastest way to obtain the value of π, as a personal challenge. More specifically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in.
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When to use cla(), clf() or close() for clearing a plot in matplotlib?
Matplotlib offers there functions:
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
Regarding this .NET unhandled exception message:
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Line continuation for list comprehensions or generator expressions in python
How are you supposed to break up a very long list comprehension?
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Speed up the loop operation in R
I have a big performance problem in R. I wrote a function that iterates over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the...