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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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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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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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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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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...
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Pretty-print C++ STL containers

... // Don't insert a delimiter if this is the first time the function is called if( _insertDelim ) (*_stream) << _delim; else _insertDelim = true; } (*_stream) << value; return *this; } pretty_ostre...
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Schema for a multilanguage database

...izability is not an issue. We can use language specific resources and have all kinds of tools that work well with them. 12 ...
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Why won't my PHP app send a 404 error?

... Your code is technically correct. If you looked at the headers of that blank page, you'd see a 404 header, and other computers/programs would be able to correctly identify the response as file not found. Of course, your users are still SOL. N...
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How do I pass JavaScript variables to PHP?

... @sergey, so i need to use ajax? Actually, i'm familliar with that. – SUN Jiangong Dec 18 '09 at 10:08 ...