This function plots a dataset in a Tk window then places 3 lines on the plot which show a predicted y value for the given x value. The lines can be clicked on and dragged to new x-values with the predicted y-values automatically updating. A table at the bottom of the graph shows the differences between the pairs of x-values and y-values.
TkApprox(x, y, type = "b", snap.to.x = FALSE, digits = 4,
cols = c("red", "#009900", "blue"), xlab = deparse(substitute(x)),
ylab = deparse(substitute(y)), hscale = 1.5, vscale = 1.5,
wait = TRUE, ...)
The x-values of the data, should be sorted
The corresponding y-values of the data
Type of plot (lines, points, both) passed to plot
If True then the lines will snap to x-values (can be changed with a checkbox in the Tk window)
Number of significant digits to display (passed to
format
)
Vector of 3 colors, used for the reference lines
Label for x-axis
Label for y-axis
Horizontal Scale of the plot, passed to tkrplot
Vertical Scale of the plot, passed to tkrplot
Should R wait for the window to be closed
Additional parameters passed to plot
If wait
is FALSE then an invisible NULL is returned, if
wait
is TRUE then an invisible list with the x and y values of
the 3 reference lines is returned.
This provides an interactive way to explore predictions from a set of
x and y values. Internally the function approxfun
is used to
make the predictions.
The x-value of the 3 reference lines can be changed by clicking and dragging the line to a new position. The x and y values are shown in the margins of the graph. Below the graph is a table with the differences (absolute value) between the pairs of points.
This can be used to find peaks/valleys in trends and to see how they differ from starting points, other peaks/valleys, etc..
# NOT RUN {
if(interactive()) {
with(ccc, TkApprox(Time2,Elevation))
}
# }
Run the code above in your browser using DataLab