[R] Scatter plot / LOESS, or LOWESS for more than one parameter

[Greg Snow]

You can also use range( MC.pH, MV.pH, na.rm=TRUE).

On Tue, Apr 24, 2012 at 1:29 PM, David Doyle <kydaviddoyle at gmail.com> wrote:
> Hi Greg,
>
> Sloved my own problem.
>
> I had some missing data "NA" in the datasets.  So I manually entered the
> ylim=range(4,6)
> and it worked!!!
>
> Thanks!!
> David
>
>
> On Tue, Apr 24, 2012 at 1:55 PM, David Doyle <kydaviddoyle at gmail.com> wrote:
>>
>> Hi Greg,
>>
>> Thanks,
>>
>> I got the 1st example to work using the following code:
>>
>>
>> data <- read.csv("http://doylesdartden.com/Monthly-pH-example.csv",
>> sep=",")
>>
>> attach(data)
>>
>> par(mfrow=c(2,1))
>> scatter.smooth( Year, MC.pH )
>> scatter.smooth( Year, MV.pH )
>>
>>
>> This is good but what I'm really looking for is to have them on the same
>> graph.
>>
>>
>> I tried your second example using the code below but got:
>>
>> "Error in plot.window(...) : need finite 'ylim' values"
>>
>> here is the code I used
>>
>>
>> data <- read.csv("http://doylesdartden.com/Monthly-pH-example.csv",
>> sep=",")
>>
>> attach(data)
>>
>>
>> plot( Year, MC.pH, ylim=range(MC.pH,MV.pH) , col='blue')
>>
>> points( Year, MV.pH, col='green' )
>>
>> lines( loess.smooth(Year,MC.pH), col='blue')
>>
>> lines( loess.smooth(Year,MV.pH), col='green')
>>
>>
>> Thanks again
>>
>> David
>>
>>
>>
>> On Tue, Apr 24, 2012 at 1:45 PM, Greg Snow <538280 at gmail.com> wrote:
>>>
>>> Assuming that you want event as the x-axis (horizontal) you can do
>>> something like (untested without reproducible data):
>>>
>>> par(mfrow=c(2,1))
>>> scatter.smooth( event, pH1 )
>>> scatter.smooth( event, pH2 )
>>>
>>> or
>>>
>>> plot( event, pH1, ylim=range(pH1,pH2) , col='blue')
>>> points( event, pH2, col='green' )
>>> lines( loess.smooth(event,pH1), col='blue')
>>> lines( loess.smooth(event,pH2), col='green')
>>>
>>> Only do the second one if pH1 and pH2 are measured on the same scale
>>> in a way that the comparison and any crossings are meaningful or if
>>> there is enough separation (but not too much) that there is no
>>> overlap, but still enough detail.
>>>
>>>
>>>
>>> On Mon, Apr 23, 2012 at 10:40 PM, R. Michael Weylandt
>>> <michael.weylandt at gmail.com> wrote:
>>> > The scatter plot is easy:
>>> >
>>> > plot(pH1 ~ pH2, data = OBJ)
>>> >
>>> > When you say a loess for each -- how do you break them up? Are there
>>> > repeat values for pH1? If so, this might be hard to do in base
>>> > graphics, but ggplot2 would make it easy:
>>> >
>>> > library(ggplot2)
>>> > ggplot(OBJ, aes(x = pH1, y = pH2)) + geom_point() + stat_smooth() +
>>> > facet_wrap(~factor(pH1))
>>> >
>>> > or something similar.
>>> >
>>> > Michael
>>> >
>>> > On Mon, Apr 23, 2012 at 11:26 PM, David Doyle <kydaviddoyle at gmail.com>
>>> > wrote:
>>> >> Hi folks.
>>> >>
>>> >> If I have the following in my "data"
>>> >>
>>> >> event    pH1    pH2
>>> >> 1            4.0     6.0
>>> >> 2            4.3     5.9
>>> >> 3            4.1     6.1
>>> >> 4            4.0     5.9
>>> >> and on and on..... for about 400 events
>>> >>
>>> >> Is there a way I can get R to plot event vs. pH1  and event vs. pH2
>>> >> and
>>> >> then do a loess or lowess line for each??
>>> >>
>>> >> Thanks in advance
>>> >> David
>>> >>
>>> >>        [[alternative HTML version deleted]]
>>> >>
>>> >> ______________________________________________
>>> >> 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.
>>> >
>>> > ______________________________________________
>>> > 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.
>>>
>>>
>>>
>>> --
>>> Gregory (Greg) L. Snow Ph.D.
>>> 538280 at gmail.com
>>
>>
>



-- 
Gregory (Greg) L. Snow Ph.D.
538280 at gmail.com