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Warning message: In `…` : invalid factor level, NA generated
... "Type" to be a character.
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3))
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = nume...
How to increase space between dotted border dots
...orders:
/*Horizontal*/
background-image: linear-gradient(to right, black 33%, rgba(255,255,255,0) 0%);
background-position: bottom;
background-size: 3px 1px;
background-repeat: repeat-x;
/*Vertical*/
background-image: linear-gradient(black 33%, rgba(255,255,255,0) 0%);
background-position: right;...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
...
3 Answers
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How to remove leading zeros from alphanumeric text?
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638
Regex is the best tool for the job; what it should be depends on the problem specification. The...
Convert String to Float in Swift
...ll also help prevent the user from copying text into your input field (12p.34, or even 12.12.41).
Obviously, if Apple does add a floatValue to Swift this will throw an exception, but it may be nice in the mean time. If they do add it later, then all you need to do to modify your code is remove the ...
How to check whether a script is running under Node.js?
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answered Mar 4 '11 at 17:34
RossRoss
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Scatterplot with too many points
... rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regular old rectangular...
How can I find script's directory with Python? [duplicate]
... Czarek TomczakCzarek Tomczak
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46
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Entity Framework and Connection Pooling
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371
Connection pooling is handled as in any other ADO.NET application. Entity connection still us...
How do you reverse a string in place in JavaScript?
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753
As long as you're dealing with simple ASCII characters, and you're happy to use built-in functio...