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How does C compute sin() and other math functions?

...ximations for both sin(x) and cos(x), then using values from a precomputed table to refine the approximation. When |x| > 2, none of the above algorithms would work, so the code starts by computing some value closer to 0 that can be fed to sin or cos instead. There's yet another branch to deal wit...
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What's the $unwind operator in MongoDB?

..., consider this array tags : [ "fun" , "good" , "fun" ] as another related table (can't be a lookup/reference table because values has some duplication) named "tags". Remember SELECT generally produces things vertical, so unwind the "tags" is to split() vertically into table "tags". The end result ...
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MySQL offset infinite rows

I would like to construct a query that displays all the results in a table, but is offset by 5 from the start of the table. As far as I can tell, MySQL's LIMIT requires a limit as well as an offset. Is there any way to do this? ...
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What are file descriptors, explained in simple terms?

...file in operating system. If your process opens 10 files then your Process table will have 10 entries for file descriptors. Similarly when you open a network socket, it is also represented by an integer and it is called Socket Descriptor. I hope you understand. ...
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MySQL Error 1215: Cannot add foreign key constraint

... the keys I'm trying to use as a foreign key are primary keys in their own tables. I have done both of these things, if I'm not mistaken. Any other help you guys could offer? ...
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How to check if object (variable) is defined in R?

...paces of attached packages, this would also fall short: > exists("data.table") [1] FALSE require(data.table) > exists("data.table", inherits = FALSE) [1] FALSE > exists("data.table") [1] TRUE The only thing I can think of to get around this -- to search in attached packages but not in ba...
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Iterate over model instance field names and values in template

.... Think of it as just a standard output of the values of that instance in table format, with the field name (verbose_name specifically if specified on the field) in the first column and the value of that field in the second column. ...
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Count number of records returned by group by

... count(*) RecordsPerGroup, COUNT(*) OVER () AS TotalRecords from temptable group by column_1, column_2, column_3, column_4 share | improve this answer | follow ...
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Table header to stay fixed at the top when user scrolls it out of view with jQuery

I am trying to design an HTML table where the header will stay at the top of the page when AND ONLY when the user scrolls it out of view. For example, the table may be 500 pixels down from the page, how do I make it so that if the user scrolls the header out of view (browser detects its no longer i...
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How to “fadeOut” & “remove” a div in jQuery?

... <title>JS Bin</title> </head> <body> <table class="table table-striped table-bordered table-hover"> <thead> <tr> <th>id</th> <th>firstname</th> <th>lastname</th> &l...