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Determine the data types of a data frame's columns
I'm using R and have loaded data into a dataframe using read.csv() . How do I determine the data type of each column in the data frame?
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What is the difference between class and instance attributes?
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Only the mutable types are shared. Like for int and str they still attached with each instances rather than class.
– Babu
Jul 17 '14 at 11:59
11
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ViewPager with previous and next page boundaries
I'm designing a view with multiple pages. I want edges of previous and next pages to be show like below and implement a 2 finger swipe to switch between pages.
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Difference between size_t and std::size_t
What are the differences between size_t and std::size_t in terms of where they are declared, when they should be used and any other differentiating features?
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64-bit version of Boost for 64-bit windows
...As a longer answer, here are my build notes for having VS .NET 2008 32-bit and 64-bit boost libraries in the same hierarchy (which is I suspect a common use case):
Build the win32 binaries
bjam --toolset=msvc-9.0 --build-type=complete stage
Create the directory lib\win32
Move the contents of sta...
Generating CSV file for Excel, how to have a newline inside a value
...ot strip off leading spaces. You will get unwanted spaces in your headings and data fields. Worse, the " that should be "protecting" that line-break in the third column will be ignored because it is not at the start of the field.
If you have non-ASCII characters (encoded in UTF-8) in the file, you ...
public friend swap member function
In the beautiful answer to the copy-and-swap-idiom there is a piece of code I need a bit of help:
2 Answers
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Hidden Features of Java
...e per-thread state.
Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interesting example is the java.util.concurrent.atomic subpackage that contains thread-safe primitives that implement the co...
What is the difference between setUp() and setUpClass() in Python unittest?
What is the difference between setUp() and setUpClass() in the Python unittest framework? Why would setup be handled in one method over the other?
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Python (and Python C API): __new__ versus __init__
...stion I'm about to ask seems to be a duplicate of Python's use of __new__ and __init__? , but regardless, it's still unclear to me exactly what the practical difference between __new__ and __init__ is.
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