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Warning message: In `…` : invalid factor level, NA generated
...of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3),stringsAsFactors=FALSE)
> fixed[1, ] <- c("lunch", 100)
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : chr ...
Do while loop in SQL Server 2008
Is there any method for implement do while loop in SQL server 2008?
5 Answers
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Is C++ context-free or context-sensitive?
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np.mean() vs np.average() in Python NumPy?
...eturned: #returned is another optional argument
scl = np.multiply(avg, 0) + scl
return avg, scl
else:
return avg
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Using a bitmask in C#
...se the Flags attribute on an enum:
[Flags]
public enum Names
{
None = 0,
Susan = 1,
Bob = 2,
Karen = 4
}
Then you'd check for a particular name as follows:
Names names = Names.Susan | Names.Bob;
// evaluates to true
bool susanIsIncluded = (names & Names.Susan) != Names.None;...
Android, canvas: How do I clear (delete contents of) a canvas (= bitmaps), living in a surfaceView?
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edited Apr 20 '11 at 12:22
answered Apr 20 '11 at 12:01
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What is the maximum size of a web browser's cookie's key?
...c. If you want to support most browsers, I suggest keeping the name under 4000 bytes, and the overall cookie size under 4093 bytes.
One thing to be careful of: if the name is too big you cannot delete the cookie (at least in JavaScript). A cookie is deleted by updating it and setting it to expire. ...
Pythonic way to check if a list is sorted or not
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edited Jan 29 '18 at 14:08
Andreas Haferburg
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an...
How to call C from Swift?
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Yes, you can of course interact with Apples C libraries. Here is explained how.
Basically, the...