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How to drop rows of Pandas DataFrame whose value in a certain column is NaN

...ilippSchwarz This error occurs if the column (EPS in the example) contains strings or other types that cannot be digested by np.isfinite(). I recommend to use pandas.notnull() that will handle this more generously. – normanius Apr 5 '18 at 10:02 ...
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How to pretty print nested dictionaries?

...he only thing I can say against it is that it don't produce a valid python string, but can almost be converted back in python. – y.petremann Oct 6 '14 at 4:49 1 ...
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Programmatically retrieve memory usage on iPhone

... 1048576)); } else { NSLog(@"Error with task_info(): %s", mach_error_string(kerr)); } } There is also a field in the structure info.virtual_size which will give you the number of bytes available virtual memory (or memory allocated to your application as potential virtual memory in any even...
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How do I provide custom cast support for my class?

...c# but note that from that example, using the explicit method, if you do: string name = "Test"; Role role = (Role) name; Then everything is fine; however, if you use: object name = "Test"; Role role = (Role) name; You will now get an InvalidCastException because string cannot be cast to Role, ...
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UITableView with fixed section headers

...ew and change it is style from the right Side/ component menu) if you have extra components such as custom views or etc. please check the table view's margins to create appropriate design. (such as height of header for sections & height of cell at index path, sections) ...
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RegEx for Javascript to allow only alphanumeric

...ex that only allows alphanumeric. So far, everyone I try only works if the string is alphanumeric, meaning contains both a letter and a number. I just want one what would allow either and not require both. ...
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How to compare objects by multiple fields

...NullPointerException when one of the fields I am comparing is null, like a String. Is there anyway to keep this compare format but allow it to be null safe? – rveach May 4 '18 at 21:15 ...
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How to create a trie in Python

... Static memory-efficient Trie structures for Python (2.x and 3.x). String data in a MARISA-trie may take up to 50x-100x less memory than in a standard Python dict; the raw lookup speed is comparable; trie also provides fast advanced methods like prefix search. Based on marisa-trie C...
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PHP: How to remove specific element from an array?

...ther 'strawberry' to demonstrate that it removes multiple instances of the string $array_without_strawberries = array_diff($array, array('strawberry')); print_r($array_without_strawberries); ...No need for extra functions or foreach loop. ...
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How to convert TimeStamp to Date in Java?

...s").parse("01/01/1970 01:00:00").getTime() / 1000; Or the opposite: String date = new java.text.SimpleDateFormat("MM/dd/yyyy HH:mm:ss").format(new java.util.Date (epoch*1000)); share | impro...