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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...lly, setdiff(bigFrame, smallFrame) gets you the extra records in the first table.
In the SQLverse this is called a
For good descriptions of all join options and set subjects, this is one of the best summaries I've seen put together to date: http://www.vertabelo.com/blog/technical-articles/sq...
What's the easiest way to escape HTML in Python?
...with all non-ascii unicode chars encoded using the xml character reference table.
– nosklo
Jun 23 '10 at 3:48
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How to escape a JSON string containing newline characters using JavaScript?
...ving one of the slashes, for example: /\\n/g should be /\n/g. See "Non-Printable Characters" at this link for details - RegExp Info
– b01
Mar 1 '13 at 16:24
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“static const” vs “#define” vs “enum”
...s pointers around.
Both (1) and (3) have a symbol in the debugger's symbol table - that makes debugging easier. It is more likely that (2) will not have a symbol, leaving you wondering what it is.
(1) cannot be used as a dimension for arrays at global scope; both (2) and (3) can.
(1) cannot be used...
In Django, how does one filter a QuerySet with dynamic field lookups?
... right. It sounds like the "field" is actually a key to a row in another table, not a column.
Specific filter buttons. Wait... That's the way the Django admin works. Specific filters are turned into buttons. And the same analysis as above applies. A few filters make sense. A large number of ...
Javascript switch vs. if…else if…else
... can add and remove functionality dynamically. You can create the dispatch table from data. You can examine it programmatically. You can build the handlers with other functions.
There's the added overhead of a function call to get to the equivalent of a "case", but the advantage (when there are lot...
Generate a random point within a circle (uniformly)
...m[] 2 Pi;
r = If[u > 1, 2 - u, u];
{r Cos[t], r Sin[t]}
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ListPlot[Table[f[], {10000}], AspectRatio -> Automatic]
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Is the creation of Java class files deterministic?
When using the same JDK (i.e. the same javac executable), are the generated class files always identical? Can there be a difference depending on the operating system or hardware ? Except of the JDK version, could there be any other factors resulting in differences? Are there any compiler opti...
Representing Monetary Values in Java [closed]
...mes a currency, too. This comes in handy when rendering monetary values in tables.
– Daniel Hiller
Nov 13 '08 at 6:01
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How to get the raw value an field?
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@Bergi The table above gives examples where number inputs can be invalid: "q", "11" (then the max is 10), "0" (when the min is 1), "" (then the element is required)
– Ian Boyd
Sep 17 '13 at 15:48
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