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How to convert a std::string to const char* or char*?
...ice that the above is not exception safe. If anything between the new call and the delete call throws, you will leak memory, as nothing will call delete for you automatically. There are two immediate ways to solve this.
boost::scoped_array
boost::scoped_array will delete the memory for you upon go...
Difference between map, applymap and apply methods in Pandas
...rame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3), columns=list('bde'), index=['Utah', 'Ohio', 'Texas', 'Oregon'])
In [117]: frame
Out[117]:
b d e
Utah -0.029638 1.081563 1.280300
Ohio 0.647747 0.831136 -1.549481
Tex...
data.table vs dplyr: can one do something well the other can't or does poorly?
...able , not so much with dplyr . I've read through some dplyr vignettes and examples that have popped up on SO, and so far my conclusions are that:
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What is the role of the bias in neural networks? [closed]
I'm aware of the gradient descent and the back-propagation algorithm. What I don't get is: when is using a bias important and how do you use it?
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MySQL stored procedure vs function, which would I use when?
I'm looking at MySQL stored procedures and function. What is the real difference?
5 Answers
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What does axis in pandas mean?
...r the flattened array) , in which axis=0 along the rows (namely, index in pandas), and axis=1 along the columns. For added clarity, one may choose to specify axis='index' (instead of axis=0) or axis='columns' (instead of axis=1).
+------------+---------+--------+
| | A | B |
+...
How to read the output from git diff?
The man page for git-diff is rather long, and explains many cases which don't seem to be necessary for a beginner. For example:
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Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...
How to find what code is run by a button or element in Chrome using Developer Tools
I'm using Chrome and my own website.
5 Answers
5
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What is the JavaScript convention for no operation?
...at is the JavaScript convention for no operation? Like a Python pass command.
6 Answers
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