Plots with Geometrically Equal Scales

DESCRIPTION:

Version of a scatterplot with scales chosen to be equal on both axes, that is 1cm represents the same units on each

USAGE:

eqscplot(x, y, ratio = 1, tol = 0.04, uin, ...)

REQUIRED ARGUMENTS:

x
vector of x values, or a 2-column matrix, or a list with components x and y

OPTIONAL ARGUMENTS:

y
vector of y values
ratio
desired ratio of units on the axes. Units on the y axis are drawn at ratio times the size of units on the x axis. Ignored if uin is specified and of length 2.
tol
proportion of white space at the margins of plot
uin
desired values for the units per inch parameter. If of length 1, the desired units per inch on the x axis.
...
further arguments for plot

VALUE:

invisibly, the values of uin used for the plot.

SIDE EFFECTS:

performs the plot.

DETAILS:

Limits for the x and y axes are chosen so that they include the data. One of the sets of limits is then stretched from the midpoint to make the units in the ratio given by ratio. Finally both are stretched by 1 + tol to move points away from the axes, and the points plotted.

Note:

Arguments ratio and uin were suggested by Bill Dunlap.

SEE ALSO:

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