Routines (alphabetical) > Routines: O > OPLOTERR Procedure

# OPLOTERR Procedure

The OPLOTERR procedure plots error bars over a previously drawn plot. A plot of X versus Y with error bars drawn from Y - Err to Y + Err is written to the output device over any plot already there.

This routine is written in the IDL language. Its source code can be found in the file `oploterr.pro` in the `lib` subdirectory of the IDL distribution.

## Syntax

OPLOTERR, [ X ,] Y , Err [, Psym ]

## Arguments

### X

An optional array of X values. The procedure checks whether or not the third parameter passed is a vector to decide if X was passed. If X is not passed, then INDGEN(Y) is assumed for the X values.

### Y

The array of Y values. Y cannot be of type string.

### Err

The array of error bar values.

### Psym

The plotting symbol to use (default = +7).

## Keywords

None

## Version History

Original | Introduced

## See Also

ERRPLOT Procedure, OPLOT Procedure, PLOT_FIELD Procedure