ERRORBAR - Draw error bars on the plotted data

Description:

Draw error bars in the X or Y directions, either treating the values in the EXCOL and EYCOL data areas as symmetric errors about the point, or as an upper limit with the XCOL or YCOL data area holding the other limit.

PONGO will plot error bars correctly even after logarithms of the data have been taken for the symmetric option, as long as the CLOG application has been used to perform the transformation (as opposed to CCMATH). For the non-symmetric case, the CCMATH application should be used to take the logarithms of the data in the EXCOL and EYCOL data areas.

Usage:

errorbar action [erterm]

Parameters:

ACTION = _CHAR (Read)

"X" or "Y" depending upon which set of error bars is to be drawn.

[The value is prompted for.]

ERTERM = _REAL (Read and Write)

The length of the terminals on the error bars: a multiple of the default length.

If the value is not specified on the command line, the current value is used. The current value is initially set to 1.0.

SYMERR = _LOGICAL (Read and Write)

If TRUE, the values in the error data areas represent a symmetric error about the values in the data columns. If FALSE, the data columns represent the lower limits, and the error columns represent the upper limits. [TRUE]