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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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How do I generate a random int number?
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The Random class is used to create random numbers. (Pseudo-random that is of course.).
Example:
Random rnd = new Random();
int month = rnd.Next(1, 13); // creates a number between 1 and 12
int dice = rnd.Next(1, 7); // creates a numbe...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...re both for the UTF-8 character encoding. The differences are in how text is sorted and compared.
Note: In MySQL you have to use utf8mb4 rather than utf8. Confusingly, utf8 is a flawed UTF-8 implementation from early MySQL versions which remains only for backward compatibility. The fixed version wa...
What is the difference between And and AndAlso in VB.NET?
In VB.NET, what is the difference between And and AndAlso ? Which should I use?
11 Answers
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How to determine if a record is just created or updated in after_save
The #new_record? function determines if a record has been saved. But it is always false in the after_save hook. Is there a way to determine whether the record is a newly created record or an old one from update?
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Why is @autoreleasepool still needed with ARC?
... need to think about memory management at all with Objective-C objects. It is not permitted to create NSAutoreleasePool s anymore, however there is a new syntax:
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Does Python's time.time() return the local or UTC timestamp?
... the number of seconds since the epoch, as seconds. Note that the "epoch" is defined as the start of January 1st, 1970 in UTC. So the epoch is defined in terms of UTC and establishes a global moment in time. No matter where you are "seconds past epoch" (time.time()) returns the same value at the ...
What is the difference between Amazon S3 and Amazon EC2 instance?
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An EC2 instance is like a remote computer running Windows or Linux and on which you can install whatever software you want, including a Web server running PHP code and a database server.
Amazon S3 is just a storage service, typically used t...
Check if a variable is of function type
Suppose I have any variable, which is defined as follows:
18 Answers
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What is the best workaround for the WCF client `using` block issue?
...ck as it's pretty much the standard way to use resources that implement IDisposable :
26 Answers
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