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Select first 4 rows of a data.frame in R
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156
Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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How to assign a Git SHA1's to a file without Git?
As I understand it when Git assigns a SHA1 hash to a file this SHA1 is unique to the file based on its contents.
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How to match “any character” in regular expression?
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Suppress command line output
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212
Because error messages often go to stderr not stdout.
Change the invocation to this:
taskkill...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
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Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won'...
How to increment a pointer address and pointer's value?
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First, the ++ operator takes precedence over the * operator, and the () operators take precede...
Use CSS3 transitions with gradient backgrounds
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SQL NVARCHAR and VARCHAR Limits
...s wrong. nvarchar(max) can store up to (and beyond sometimes) 2GB of data (1 billion double byte characters).
From nchar and nvarchar in Books online the grammar is
nvarchar [ ( n | max ) ]
The | character means these are alternatives. i.e. you specify either n or the literal max.
If you choose to ...
Secondary axis with twinx(): how to add to legend?
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391
You can easily add a second legend by adding the line:
ax2.legend(loc=0)
You'll get this:
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