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what is the most efficient way of counting occurrences in pandas?
I have a large (about 12M rows) dataframe df with say:
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How to find if a given key exists in a C++ std::map
I'm trying to check if a given key is in a map and somewhat can't do it:
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Accessing attributes from an AngularJS directive
My AngularJS template contains some custom HTML syntax like:
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Secret copy to clipboard JavaScript function in Chrome and Firefox?
Update
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Deleting rows with MySQL LEFT JOIN
I have two tables, one for job deadlines, one for describe a job. Each job can take a status and some statuses means the jobs' deadlines must be deleted from the other table.
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Why does sed not replace all occurrences?
If I run this code in bash:
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What is the difference between git am and git apply?
Both git am and git apply can be used to apply patches. I fail to see the difference. I see a difference now: git am automatically commits whereas git apply only touches the files but doesn't create a commit. Is that the only difference?
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Entity framework code-first null foreign key
I have a User < Country model. A user belongs to a country, but may not belong to any (null foreign key).
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How to switch back to 'master' with git?
I have made my first commit; then created a branch (let's say branch1).
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How to name variables on the fly?
Is it possible to create new variable names on the fly?
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