REFERENCE Subcommand (SPCHART command)
REFERENCE
controls which vertical reference lines are displayed on a process
capability chart. It only applies when the chart specification is /CPCHART
.
SL. Vertical reference lines are displayed at the specified values of LSL and USL as well as at the value of TARGET if specified. This is the default.
SIGMAS. Vertical reference
lines are displayed at the process mean and at a specified number
of capability sigmas above and below the mean. The number
of capability sigmas is given by the value of the SIGMAS
subcommand, which is 3 by default.
NONE. Specifies that no reference lines will be displayed. This
is an alternative to SL
and/or SIGMAS
and cannot be used in combination
with them.