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At runtime, find all classes in a Java application that extend a base class
...ns. I mistakenly figured this would be as easy as it is in the .Net world and this answer has saved me a lot of time.
– akmad
Oct 1 '12 at 19:55
1
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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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Django TemplateDoesNotExist?
My local machine is running Python 2.5 and Nginx on Ubuntu 8.10, with Django builded from latest development trunk.
20 Answ...
C# Float expression: strange behavior when casting the result float to int
...ing (it's actually the value 61.99999809265137 when expressed as a double) and that your question is only about why two seemingly identical computations result in the wrong value.
The answer is that in the case of (int)(6.2f * 10), you are taking the double value 61.99999809265137 and truncating it...
Prepend text to beginning of string
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Perhaps this should be the new standard: each post must also include relevant XKCD.
– Brett84c
Sep 12 '18 at 20:33
1
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SQL Data Reader - handling Null column values
...der.GetString(indexFirstName);
}
That's your only reliable way to detect and handle this situation.
I wrapped those things into extension methods and tend to return a default value if the column is indeed null:
public static string SafeGetString(this SqlDataReader reader, int colIndex)
{
if(!...
How to get a file or blob from an object URL?
I am allowing the user to load images into a page via drag&drop and other methods. When an image is dropped, I'm using URL.createObjectURL to convert to an object URL to display the image. I am not revoking the url, as I do reuse it.
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Calling a Method From a String With the Method's Name in Ruby
... module function
FileUtils.send('pwd')
# or
FileUtils.public_send(:pwd)
and a locally defined method
def load()
puts "load() function was executed."
end
send('load')
# or
public_send('load')
Documentation:
Object#public_send
Object#send
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Determine whether an array contains a value [duplicate]
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fixed the comparison and added the missing return -1; please note that according to the ES5 spec, this method will behave differently from the native one in case ofsigned zeroes and NaNs (see 15.4.4.14 and 9.12 vs. 11.9.6)
–...
What is the difference between a JavaBean and a POJO?
I'm not sure about the difference. I'm using Hibernate and, in some books, they use JavaBean and POJO as an interchangeable term. I want to know if there is a difference, not just in the Hibernate context, but as general concepts.
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