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Python initializing a list of lists [duplicate]
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The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the sam...
How to convert IPython notebooks to PDF and HTML?
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If you have LaTeX installed you can download as PDF directly from Jupyter notebook with File -> Download as -> PDF via LaTeX (.pdf). Otherwise follow these two steps.
For HTML output, you should now use Jupyter in place of IPython and sele...
Case insensitive replace
...ld be useful if the to-replace value was passed into a function, so it's really more of a good example than anything else.
– Blair Conrad
Nov 9 '14 at 23:19
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How to know what the 'errno' means?
When calling execl(...) , I get an errno=2 . What does it mean? How can I know the meaning of this errno ?
15 Answers
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user authentication libraries for node.js?
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Among all auth packages for node I selected passport. It's well-documented and easy to use, and supports more strategies.
– tech-man
May 14 '12 at 4:16
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How to sum array of numbers in Ruby?
... using array.map(...).inject(...) is inefficient, you will iterate through all data twice. Try array.inject(0) { |sum, product| sum += product.price }
– everett1992
Apr 4 '13 at 6:11
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How do I declare a 2d array in C++ using new?
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A dynamic 2D array is basically an array of pointers to arrays. You can initialize it using a loop, like this:
int** a = new int*[rowCount];
for(int i = 0; i < rowCount; ++i)
a[i] = new int[colCount];
The above, for colCount= 5 and rowCount =...
What is the difference between `sorted(list)` vs `list.sort()`?
...sorts the list in-place, mutating the list indices, and returns None (like all in-place operations).
sorted() works on any iterable, not just lists. Strings, tuples, dictionaries (you'll get the keys), generators, etc., returning a list containing all elements, sorted.
Use list.sort() when you wa...
jquery variable syntax [duplicate]
... 2;
alert($ + $$);
jQuery just assigns it's core function to a variable called $. The code you have assigns this to a local variable called self and the results of calling jQuery with this as an argument to a global variable called $self.
It's ugly, dirty, confusing, but $, self and $self are all...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
Performance associated with Arrays and Objects in JavaScript (especially Google V8) would be very interesting to document. I find no comprehensive article on this topic anywhere on the Internet.
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