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What are the differences between numpy arrays and matrices? Which one should I use?

...ted/numpy.matrix.html As other answers already state that you can achieve all the operations with NumPy arrays. share | improve this answer | follow | ...
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Tracking the script execution time in PHP

..."; echo "It spent " . rutime($ru, $rustart, "stime") . " ms in system calls\n"; Note that you don't need to calculate a difference if you are spawning a php instance for every test. share | im...
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How to change the type of a field?

...(x)) and then save the document again. If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax. In response to the second comment below. Change the field bad from a number to a string in collection foo. db.foo.find( { 'bad' :...
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Find object in list that has attribute equal to some value (that meets any condition)

...eat solution, but how do i modify your line so that I can make x.value actually mean x.fieldMemberName where that name is stored in value? field = "name" next((x for x in test_list if x.field == value), None) so that in this case, i am actually checking against x.name, not x.field ...
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Is bool a native C type?

... in the current C - C99, but not in C89/90. In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h. Note, BTW, t...
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How to extract the decision rules from scikit-learn decision-tree?

...sion of sklearn, because some values of tree.tree_.feature are -2 (specifically for leaf nodes). There is no need to have multiple if statements in the recursive function, just one is fine. share | ...
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What is a regular expression which will match a valid domain name without a subdomain?

... This should match all cases I think: ^([a-z0-9])(([a-z0-9-]{1,61})?[a-z0-9]{1})?(\.[a-z0-9](([a-z0-9-]{1,61})?[a-z0-9]{1})?)?(\.[a-zA-Z]{2,4})+$ – transilvlad May 16 '13 at 16:38 ...
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How to use if - else structure in a batch file?

...stion about if - else structure in a batch file. Each command runs individually, but I couldn't use "if - else" blocks safely so these parts of my programme doesn't work. How can I do make these parts run? Thank you. ...
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Where is SQL Server Management Studio 2012?

... SQL Server 2008 R2 and Visual Studio 2008 and 2010 on my laptop. I've installed SQL Server 2012 and have finally got SQL Server Data Tools to show up, so that I can create SSRS reports in Visual Studio 2010. ...
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Is there an IDictionary implementation that, on missing key, returns the default value instead of th

... Indeed, that won't be efficient at all. You could always write an extension method: public static TValue GetValueOrDefault<TKey,TValue> (this IDictionary<TKey, TValue> dictionary, TKey key) { TValue ret; // Ignore return value dic...