Usage
linearRelation(mydata,
x = "nox",
y = "no2",
period = "monthly",
condition = FALSE,
n = 20,
rsq.thresh = 0,
ylim = c(0, 20),
ylab = paste("slope from ", y, " = m.", x, " + c", sep = ""),
xlab = NULL,
auto.text = TRUE,
cols = NULL,
main = "",
span = 0.3,...)
Arguments
mydata
A data frame minimally containing date
and two
pollutants.
x
First pollutant that when plotted would appear on the x-axis
of a relationship e.g. x = "nox"
.
y
Second pollutant that when plotted would appear on the y-axis
of a relationship e.g. y = "pm10"
.
period
A range of different time periods can be
analysed. "monthly" will plot a monthly time series and "weekly" a
weekly time series of the relationship between x
and
y
. "hour" will show the diurnal relationship between
condition
For period = "hour"
, period = "day"
and
period = "day.hour"
, setting condition = TRUE
will plot
the relationships split by year. This is useful for seeing how the
relationships may be changing o
n
The minimum number of points to be sent to the linear
model. Because there may only be a few points e.g. hours where two
pollutants are available over one week, n
can be set to ensure
that at least n
points are sent to t
rsq.thresh
The minimum correlation coefficient (R2) allowed. If
the relationship between x
and y
is not very good for a
particular period, setting rsq.thresh
can help to remove those
periods where the relationship is n
ylim
y-axis limits, specified by the user.
ylab
y-axis title, specified by the user.
xlab
x-axis title, specified by the user.
auto.text
Either TRUE
(default) or FALSE
. If TRUE
titles and axis labels will automatically try and format pollutant
names and units properly e.g. by subscripting the 2 in NO2.
cols
Predefined colour scheme, currently only enabled for
"greyscale"
.
span
span for loess
fit. Controls the fit line: lower
values produce a more "wiggly" fit.
...
Other graphical parameters. A useful one to remove the
strip with the date range on at the top of the plot is to set
strip = FALSE
.