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How to check whether a pandas DataFrame is empty?
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You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print('DataFrame is empty!')
Source: Pandas Documentation
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What is a Portable Class Library?
On MSDN I noticed a section about a Portable Class Library , under Version Information.
4 Answers
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How to create a unique index on a NULL column?
I am using SQL Server 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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JavaScript: Class.method vs. Class.prototype.method
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Yes, the first function has no relationship with an object instance of that constructor function, you can consider it like a 'static method'.
In JavaScript functions are first-class objects, that means you can treat them just like any objec...
Difference between a Postback and a Callback
I keep on hearing this words ' callback ' and ' postback ' tossed around.
What is the difference between two ?
6 Answers...
E731 do not assign a lambda expression, use a def
I get this pep8 warning whenever I use lambda expressions. Are lambda expressions not recommended? If not why?
4 Answers
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What does this square bracket and parenthesis bracket notation mean [first1,last1)?
I have seen number ranges represented as [first1,last1) and [first2,last2) .
4 Answers
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What's the idiomatic syntax for prepending to a short python list?
list.append() is the obvious choice for adding to the end of a list. Here's a reasonable explanation for the missing list.prepend() . Assuming my list is short and performance concerns are negligible, is
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How do browsers pause/change Javascript when tab or window is not active?
Background: I'm doing some user interface tests that need to detect if people are paying attention or not. But, this question is not about the page visibility API .
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Under what circumstances is an SqlConnection automatically enlisted in an ambient TransactionScope T
...o be "enlisted" in a transaction? Does it simply mean that commands I execute on the connection will participate in the transaction?
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