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How to select the rows with maximum values in each group with dplyr? [duplicate]
...n the comments, slice may be preferred here as per @RoyalITS' answer below if you strictly only want 1 row per group. This answer will return multiple rows if there are multiple with an identical maximum value.
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Can't use modulus on doubles?
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@Paul: That's probably not a bug. If angle is, say, 359.9999999, then both angle and fmod(angle, 360) are likely to be displayed as 360. (Add more 9s as needed.) Try printing the values with, say, 50 digits of precision.
– Keith Thompson...
How to get just numeric part of CSS property with jQuery?
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you might want to add the radix (10) to parseInt if you are using this solution.
– asawilliams
Jun 8 '11 at 16:45
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What is the purpose of Order By 1 in SQL select statement?
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It's not a recommended practice, because:
It's not obvious/explicit
If the column order changes, the query is still valid so you risk ordering by something you didn't intend
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What does Java option -Xmx stand for? [duplicate]
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see here: Java Tool Doc, it says,
-Xmxn
Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 64MB. T...
How to fix PCH error?
...n key pressed) works for most people. See the selected answer by @gaige.
If you're unlike most people (myself included) and this still causes you trouble XCode has likely left your shared precompiled headers elsewhere. For me they were in a folder similar to this:
/var/folders/<some random tw...
Converting string into datetime
... have to know ahead of time to exclude that part of the format string, but if you want a date instead of a datetime, going through datetime handles it nicely: datetime.strptime('Jun 1 2005', '%b %d %Y').date() == date(2005, 6, 1)
– Izkata
Nov 11 '14 at 20:02
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Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?
... it may not in fact be a System.Exception.
See CLI spec section 10.5 (specifically CLS rule 40) for more details
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Where does VBA Debug.Print log to?
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This is true if you are in an office application which supports VBA, but if you are using via WSH you may need to use MsgBox (shudder) or some similar technique as the immediate window is not available.
– AJ.
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Functional programming vs Object Oriented programming [closed]
...oose functional programming over object oriented?
When you anticipate a different kind of software evolution:
Object-oriented languages are good when you have a fixed set of operations on things, and as your code evolves, you primarily add new things. This can be accomplished by adding new clas...