R help - Jul 2009 - yaxp problem for more irregular time series in one plot

Good day,

I'm trying to get more time series in one plot. As there are bigger
differences in values of variables I need logaritmic y axis.

The code I use is the following:

nvz_3_data <- read.csv('/home/tomas/R_outputs/nvz_3.csv')
date <- (nvz_3_data$date)
NO3 <- (nvz_3_data$NO3)
NH4 <- (nvz_3_data$NH4)
date_p <- as.POSIXct(date, "CET")
par(mfrow=c(2,1), ylog = TRUE, yaxp = c(0.01, 100, 3))
plot(date_p, NO3, log = "y", type = "l", col =
"darkred", main = "NVZ-1",
xlab = "time", ylab = "NO3-" )
lines(date_p, NH4, col = "darkblue", lty = "dotted")
plot(date_p, NH4, log = "y", type = "l", col =
"darkblue", main = "NVZ-1",
xlab = "time", ylab = "NH4+" )

So, as I anderstood, extreme (max and min) values on the y axis are
conntrolled byt the yaxp, but it is ignored on the plot, and the NH4
values are out of the plot (see the attached picture). Do somebody know
what I am doing wrong?

Many thanks in advance

Tomas

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lanczos at fns.uniba.sk schrieb:
> Good day,
>
> I'm trying to get more time series in one plot. As there are bigger
> differences in values of variables I need logaritmic y axis.
>
> The code I use is the following:
>
> nvz_3_data <- read.csv('/home/tomas/R_outputs/nvz_3.csv')
> date <- (nvz_3_data$date)
> NO3 <- (nvz_3_data$NO3)
> NH4 <- (nvz_3_data$NH4)
> date_p <- as.POSIXct(date, "CET")
> par(mfrow=c(2,1), ylog = TRUE, yaxp = c(0.01, 100, 3))
> plot(date_p, NO3, log = "y", type = "l", col =
"darkred", main = "NVZ-1",
> xlab = "time", ylab = "NO3-" )
> lines(date_p, NH4, col = "darkblue", lty = "dotted")
> plot(date_p, NH4, log = "y", type = "l", col =
"darkblue", main = "NVZ-1",
> xlab = "time", ylab = "NH4+" )
>
> So, as I anderstood, extreme (max and min) values on the y axis are
> conntrolled byt the yaxp, but it is ignored on the plot, and the NH4
> values are out of the plot (see the attached picture). Do somebody know
> what I am doing wrong?
>
> Many thanks in advance
>
> Tomas
>
>   
>
> ------------------------------------------------------------------------
>
> ------------------------------------------------------------------------
>
> ______________________________________________
> 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.
>   
Hey Thomas,

the yaxp command isn't ignored. The problem is the boundary of your
y-data. Your plot is adjusted to the NO3 data and because the higher
values of your NH4 you won't be able to see it on the plot. A solution
lies in implementing the ylim command in your plot.
Here is your changed code:

nvz_3_data <- read.csv('/home/tomas/R_outputs/nvz_3.csv')
date <- (nvz_3_data$date)
NO3 <- (nvz_3_data$NO3)
NH4 <- (nvz_3_data$NH4)
maxy<-max(NO3,NH4)                   ## the maximum value of your data
miny<-min(NO3[NO3>0],NH4[NH4>0])     ## the minimum value of your data
which are > 0 (because: log)
date_p <- as.POSIXct(date, "CET")
par(mfrow=c(2,1), ylog = TRUE, yaxp = c(0.01, 100, 3))
plot(date_p, NO3,log = "y", ylim=c(miny,maxy), type = "l",
col = "darkred",
 main = "NVZ-1", xlab = "time", ylab = "NO3-" )
lines(date_p, NH4, col = "darkblue", lty = "dotted")
plot(date_p, NH4, log = "y", type = "l", col =
"darkblue", main = "NVZ-1",
xlab = "time", ylab = "NH4+" )

I hope, I was able to help you.

Regards,
Christian
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