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Aggregate / summarize multiple variables per group (e.g. sum, mean)
....122369 -128.122613
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23 2000 12 63.436507 449.794454
24 2001 12 999.472226 922.726589
See ?aggregate, the formula argument and the examples.
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Selenium WebDriver: Wait for complex page with JavaScript to load
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Petr JanečekPetr Janeček
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MongoDB not equal to
...u would like to use $not is:
db.inventory.find( { price: { $not: { $gt: 1.99 } } } )
That would select all documents where:
The price field value is less than or equal to 1.99 or the price
Field does not exist
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Are negative array indexes allowed in C?
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That is correct. From C99 §6.5.2.1/2:
The definition of the subscript
operator [] is that E1[E2] is
identical to (*((E1)+(E2))).
There's no magic. It's a 1-1 equivalence. As always when dereferencing a pointer (*), you need to be sure...
Get full path without filename from path that includes filename
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Jon HannaJon Hanna
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Should URL be case sensitive?
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I guess "be liberal in what you accept and conservative in what you send" (IETF speak) would be my guideline.
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What does the caret (‘^’) mean in C++/CLI?
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Bakudan
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answered Jan 17 '13 at 11:45
salomonsalomon
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How can I pass a parameter to a setTimeout() callback?
... PhmsFabio Phms
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Can an Android NFC phone act as an NFC tag?
... MakeSomethingMakeSomething
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This Handler class should be static or leaks might occur: IncomingHandler
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Aaron
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answered Feb 11 '13 at 0:55
MichaelMichael
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