How to plot function of multiple variables in R by initializing all variables but one

Question

What's the easiest way to plot a function of multiple variables in a 2D graph by giving some of the input parameters a value. Let's consider a simple example

my.function<-function(a,b,x){a*x^2+b}

Now I want to plot the simple parabola where a=1 an b=0 . So I define a new function: new.function<-function(x){my.function(1,0,x)}; plot(new.function) .

Is there any way where I can plot the function without defining new.function?

Normally I use Mathematica and in Mathematica it would be:

Plot[my.function[1,0,x],{x ... }]

Basically the same in R `plot(function(x) { my.function(1,0,x) })` — G5W, May 07 '17 at 14:24
Or you can use `curve` like `curve(my.function(1, 0, x), from=0, to=10)`. — lmo, May 07 '17 at 15:51

Dale Kube · Answer 1 · 2017-05-11T14:52:52.253

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You should not need to define a new function. You can use the original function, my.function, and pass in x-values 1 through 10 to plot the parabola:

my.function <- function(a,b,x){a*x^2+b}
x <- 1:10
y <- my.function(a=1,b=0,x=x)
plot(y~x)

edited May 11 '17 at 14:52

answered May 07 '17 at 15:01

Dale Kube

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The function is vectorized, so no need for `sapply`. `y <- my.function(a = 1, b = 0, x = 1:10)` works fine. – Gregor Thomas May 09 '17 at 23:07
Thanks for pointing that out. I edited my post. It's much more simple without `sapply()`. – Dale Kube May 11 '17 at 14:53

score 1 · Accepted Answer · answered May 09 '17 at 23:05

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For future readers, I am sharing @G5W 's comment as answer in here:

plot(function(x) { my.function(1,0,x) })

I believe this is the best way of those provided in here

answered May 09 '17 at 23:05

k.dkhk

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How to plot function of multiple variables in R by initializing all variables but one

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