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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
I have a data.frame that looks like this.
6 Answers
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Tool to convert Python code to be PEP8 compliant
...torming" (the entire project) has several negative side-effects:
lots of merge-conflicts
break git blame
make code review difficult
As an alternative (and thanks to @y-p for the idea), I wrote a small package which autopep8s only those lines which you have been working on since the last commit/b...
Ruby class instance variable vs. class variable
...nce variable on a class (not on an instance of that class) you can store something common to that class without having sub-classes automatically also get them (and vice-versa). With class variables, you have the convenience of not having to write self.class from an instance object, and (when desirab...
Why wasn't PyPy included in standard Python?
...nline Python distributions. Wouldn't things like JIT compilation and lower memory footprint greatly improve the speeds of all Python code?
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Find a string by searching all tables in SQL Server Management Studio 2008
...way to search for a string in all tables of a database in SQL Server Management Studio 2008?
8 Answers
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Algorithm to detect intersection of two rectangles?
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The standard method would be to do the separating axis test (do a google search on that).
In short:
Two objects don't intersect if you can find a line that separates the two objects. e.g. the objects / all points of an object are on di...
Is it possible for a computer to “learn” a regular expression by user-provided examples?
...ar language is equivalent to a finite automaton, it is possible to learn some regular expressions by a program. Kearns and Valiant show some cases where it is not possible to learn a finite automaton. A related problem is learning hidden Markov Models, which are probabilistic automata that can descr...
Which is better: … or …
...as it as optional, defaulting to text/javascript. HTML5 is now widely implemented, so if you use the HTML5 doctype, <script>...</script> is valid and a good choice.
As to what should go in the type attribute, the MIME type application/javascript registered in 2006 is intended to replac...
Why should a function have only one exit-point? [closed]
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There are different schools of thought, and it largely comes down to personal preference.
One is that it is less confusing if there is only a single exit point - you have a single path through the method and you know where to look for the exit. On the minus side if you use indenta...
Get the full URL in PHP
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Not much you can do about it, this is the proper method for the question asked.
– Mfoo
Apr 27 '13 at 12:45
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