* the error output.
*/
public void addPlotToolBar(String location) {
if (location.equalsIgnoreCase(EAST)) {
removePlotToolBar();
plotToolBar = new PlotToolBar(this);
plotToolBar.setFloatable(false);
add(plotToolBar, EAST);
} else if (location.equalsIgnoreCase(SOUTH)) {
removePlotToolBar();
plotToolBar = new PlotToolBar(this);
plotToolBar.setFloatable(false);
add(plotToolBar, SOUTH);
} else if (location.equalsIgnoreCase(WEST)) {
removePlotToolBar();
plotToolBar = new PlotToolBar(this);
plotToolBar.setFloatable(false);
add(plotToolBar, WEST);
} else if (location.equalsIgnoreCase(NORTH)) {
removePlotToolBar();
plotToolBar = new PlotToolBar(this);
plotToolBar.setFloatable(false);
add(plotToolBar, NORTH);
} else {
System.err.println("Location " + location + " is unknonw.");
}