NOTE({valuexpr,}xexpr,yexpr);   Put text label and optional value on plot

The NOTE procedure causes DAN to output a text string to the graphics
area of a plot.  The text may optionally be followed by a specified
numeric value.  The text is taken from the most recently processed TEXT
statement.  The lower left corner of the first character in the text is
output starting at the coordinates given by 'xexpr' and 'yexpr'.  These
coordinates are given with respect to the current scaling values, hence
the YMIN, YMAX, etc.  values must have been set before the NOTE
statement is executed.

A text only message is output if only the x and y coordinates are
specified in the NOTE statement.  That is, if the NOTE statement only
contains two parameters then they are assumed to be x and y
coordinates, and a value is not appended to the text string.
+
If any of the expressions in the statement contains a variable then the
NOTE statement will cause an implicit loop to be executed with multiple
notes being output; one for each step in the implicit loop.  This feature
can be used to label multiple points along a trace or maintain a running
value that is updated as the trace is output.

This procedure may be used for annotating graphs with calculated values.
The CONNECT procedure may be used to visually attach a NOTE to a point on
a plot.
