R help - Jun 2008 - Superimposing Line over Histogram in Density Plot

Hi,

Currently I have a density plot generated with this
snippet.

Is there a way I can add a line curve on top of it?
I mean in one figure


__BEGIN__
   myhist <- hist(x
                col="blue",
                main = "Density Plot",
                xlab = "Exp Level",
    )
__END__


- Gundala Viswanath
Jakarta - Indonesia

try something like this:

x <- rnorm(200)
hist(x, col = "blue", freq = FALSE)
lines(density(x), col = "red", lwd = 2)


I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm


----- Original Message ----- 
From: "Gundala Viswanath" <gundalav at gmail.com>
To: <r-help at stat.math.ethz.ch>
Sent: Monday, June 16, 2008 8:25 AM
Subject: [R] Superimposing Line over Histogram in Density Plot

> Hi,
>
> Currently I have a density plot generated with this
> snippet.
>
> Is there a way I can add a line curve on top of it?
> I mean in one figure
>
>
> __BEGIN__
>   myhist <- hist(x
>                col="blue",
>                main = "Density Plot",
>                xlab = "Exp Level",
>    )
> __END__
>
>
> - Gundala Viswanath
> Jakarta - Indonesia
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

How can I swap the column names at the same time ?
 
> m <- cbind(x=1:3, y=2:4, z=3:5)> m     x y z[1,] 1 2 3[2,] 2 3 4[3,]
3 4 5
> m[,c(1,2)] <- m[,c(2,1)]> m     x y z[1,] 2 1 3[2,] 3 2 4[3,] 4 3 5
_________________________________________________________________


	[[alternative HTML version deleted]]

Look here:

http://msenux.redwoods.edu/mathdept/R/CentralLimit.php

D.

On Jun 15, 2008, at 11:25 PM, Gundala Viswanath wrote:
> Hi,
>
> Currently I have a density plot generated with this
> snippet.
>
> Is there a way I can add a line curve on top of it?
> I mean in one figure
>
>
> __BEGIN__
>    myhist <- hist(x
>                 col="blue",
>                 main = "Density Plot",
>                 xlab = "Exp Level",
>     )
> __END__
>
>
> - Gundala Viswanath
> Jakarta - Indonesia
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting- 
> guide.html
> and provide commented, minimal, self-contained, reproducible code.

I do it a bit differently:
Once you've got myhist, you can plot a line on the existing histogram 
plot with something like:

smoo<-spline(myhist$breaks[1:length(myhist$breaks)-1],myhist$counts)
lines(smoo$x,smoo$y,col='green')

You'll have to muck a bit with scale factors to make the spline curve 
"match up" with the histogram plot's actual x-axis values.
(actually, that snippet is part of my conversion from histogram data to 
a bar chart that "looks" like a histogram, with the spline curve
overlaid).

Carl





try something like this:

x <- rnorm(200)
hist(x, col = "blue", freq = FALSE)
lines(density(x), col = "red", lwd = 2)

I hope it helps.

Best,
Dimitris


 >
 > Currently I have a density plot generated with this
 > snippet.
 >
 > Is there a way I can add a line curve on top of it?
 > I mean in one figure
 >
 >
 > __BEGIN__
 > myhist <- hist(x
 > col="blue",
 > main = "Density Plot",
 > xlab = "Exp Level",
 > )
 > __END__
 >
 >