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Compare floats in php
...same value do not need to actually be identical. So if $a is a literal .17 and $b arrives there through a calculation it can well be that they are different, albeit both display the same value.
Usually you never compare floating-point values for equality like this, you need to use a smallest accept...
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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check if directory exists and delete in one command unix
Is it possible to check if a directory exists and delete if it does,in Unix using a single command? I have situation where I use ANT 'sshexec' task where I can run only a single command in the remote machine. And I need to check if directory exists and delete it...
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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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What is time_t ultimately a typedef to?
I searched my Linux box and saw this typedef:
10 Answers
10
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In Hibernate Validator 4.1+, what is the difference between @NotNull, @NotEmpty, and @NotBlank?
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@NotEmpty: The CharSequence, Collection, Map or Array object is not null and size > 0.
@NotBlank: The string is not null and the trimmed length is greater than zero.
To help you understand, let's look into how these constraints are defined and carried out (I'm using version 4.1):
The @Not...
Changing a specific column name in pandas DataFrame
...index=None, columns=None, copy=True, inplace=False)
Docstring:
Alter index and / or columns using input function or
functions. Function / dict values must be unique (1-to-1). Labels not
contained in a dict / Series will be left as-is.
Parameters
----------
index : dict-like or function, optional
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Access lapply index names inside FUN
... n=names(x))
Here I use lapply over the indices of x, but also pass in x and the names of x. As you can see, the order of the function arguments can be anything - lapply will pass in the "element" (here the index) to the first argument not specified among the extra ones. In this case, I specify y ...
Why does one hot encoding improve machine learning performance?
...ced that when One Hot encoding is used on a particular data set (a matrix) and used as training data for learning algorithms, it gives significantly better results with respect to prediction accuracy, compared to using the original matrix itself as training data. How does this performance increase h...
How to convert currentTimeMillis to a date in Java?
...ted date do not represent correct time of the server. Is there any way to handle this elegantly ?
11 Answers
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