[R] using "substitute" inside a legend

[Uwe Ligges]

Mathew Fox wrote:
> Hello list,
> 
> I have a linear regression:
> 
> mylm = lm(y~x-1)
> 
> I've been reading old mail postings as well as the plotmath demo and I came
> up with a way to print an equation resulting from a linear regression:
> 
> model = substitute(list("y"==slope%*%"x", R^2==rsq),
> list(slope=round(mylm$coefficients[[1]],2),rsq=round(summary(mylm)$adj.r.squared,
> 2)))
> 
> I have four models and I need to list each equation in a legend. I'm using:
> 
> legend(20, 120, title = "fitted models", c(model1, model2, model3, model4),
> lty=1, col=c("blue", "red", "black", "green"))


legend(20, 120, title = "fitted models",
     do.call("expression", list(model1, model2, model3, model4)),
     lty=1, col=c("blue", "red", "black", "green"))

Uwe Ligges


> But this only works when I have up to two models. With four models the
> formatting is lost. I suspect the concatenation converts the objects into
> List and this destroys the formatting.
> 
> Does anybody have any suggestions? The main difficulty I have is
> substituting R squared / slope values from a linear model into a
> mathematical expression.
> 
> Thanks,
> 
> M.
> 
> 	[[alternative HTML version deleted]]
> 
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