[R] Question about curve function

[Matt Shotwell]

I think there is trouble because expr in curve(expr) may be the name of
a function, and it's ambiguous whether 'x' should be interpreted as a
mathematical expression involving x, or the name of a function. Here are
some examples that work:

curve(I(x))
curve(1*x)

On Sun, 2011-06-05 at 12:07 -0500, Abhilash Balakrishnan wrote:
> Dear Sirs,
> 
> I am a new user of the R package.  When I try to use the curve function it
> confuses me.
> 
> > curve(x^2)
> Works fine.
> 
> > curve(x)
> Makes a complaint I don't understand.  Why is x^2 valid and x is not?
> 
> I check the documentation of curve, and it says the first argument must be
> an expression containing x.
> 
> > expression(x)
> Is an expression containing x.
> 
> > curve(expression(x))
> Makes a different complaint and mentions different lengths of x and y (but I
> use no y here).
> 
> I understand that plotting the function y(x) = x is rather silly, but I want
> to know what I am doing wrong, for the sake of my understanding of how R
> works.
> 
> Thank you for support.
> Abhilash B.
> 
> 	[[alternative HTML version deleted]]
> 
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