FileIn f("/path/to/my.file");
String ln = f.GetLine();
String val1, val2;
Vector<double> x, y;
while( !f.IsEof()) {
	SplitTo(ln, '\t', val1, val2);  // for tab delimited values, change delimiter as needed
	x.Add(StrDbl(TrimBoth(val1)));
	y << StrDbl(TrimBoth(val2));    // this is same as y.Add, just bit easier to read in some cases
	ln = f.GetLine();
}

	doPlot.pltType.Add(0,"2D");
	doPlot.pltType.Add(1,"3D");
	doPlot.pltType.Add(2,"Contour");