[R] Best Fit line trouble with rsruby

[Deadpool]

Hello, I am using R, through rsruby, to create a graph and best fit line for
a set of data points, regarding data collected in a Chemistry class. The
problem is that although the graph functions perfectly properly, the best
fit line will not work.

I initially used code I pretty much copied from a website with a tutorial on
this, which was:

graphData.png("/code/Beer's-Law Graph.png")
concentration = p1Conc
absorbance = p1AbsorbanceArray
graphData.assign('x', p1Conc)
graphData.assign('y', p1AbsorbanceArray)
fit = graphData.lm('x ~ y')
graphData.plot(concentration, absorbance)
graphData.abline(fit["coefficients"]["(Intercept)"],
fit["coefficients"]["y"])
puts fit["coefficients"]
graphData.eval_R("dev.off()")

(p1Conc and p1AbsorbanceArray are arrays)

This worked for the graph, but the best fit line looked (and the
infinitesimally small slope supported) like it was based off a single point.
The site said they had to define something in the R interpreter first, but
didn't elaborate, so I gave it a go, and obviously it didn't work.

I then tried something like this, as I thought the conversion from the array
to the string in the assign function was causing the problem with the best
fit line.

graphData = RSRuby.instance
graphData.png("/code/Beer's-Law Graph.png")
concentration = graphData.c(p1Conc[0..(p1SampNum - 1)])
absorbance = graphData.c(p1AbsorbanceArray[0..(p1SampNum - 1)])
fit = graphData.lm(concentration ~ absorbance)
graphData.plot(concentration, absorbance)
graphData.abline(fit["coefficients"]["(Intercept)"],
fit["coefficients"][absorbance])
puts fit["coefficients"]
print "\n"
graphData.eval_R("dev.off()")

Basically trying to bypass that, and feed the numbers straight from the
array into the best fit line, but the program was giving me an error, saying
it didn't know what ~ was for an array (should note I tried it first without
doing the graphData.c thing, but that didn't work and as the .c function
didn't seem to store things as an array, I thought that might work, it
didn't, as it does store data as an array).

So basically I'm stuck. Not sure if anyone has any experience with rsruby,
but any help would be appreciated. I'm pretty sure the fit =
graphData.lm(etcetera) line is where the trouble is, but not sure how to
handle it.
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