Perhaps the following code example could help you. It uses new graphics in IDL 8.x. sinewave = SIN(2.0*FINDGEN(200)*!PI/25.0)*EXP(-0.02*FINDGEN(200)) cosine = COS(2.0*FINDGEN(200)*!PI/25.0)*EXP(-0.02*FINDGEN(200)) ; create 3 plots myPlot = PLOT(sinewave, '-r',$ POSITION=[.05,.55,.40,.95]) myPlotToo = PLOT(cosine, '-b',$ /CURRENT, POSITION=[.25,.05,.65,.45]) myThirdPlot = PLOT(sinewave, '-r',$ /CURRENT, POSITION=[.50,.55,.90,.95]) ; Overplot a graphic onto the first plot. aPlot = PLOT(cosine, '-b', OVERPLOT=myPlot, TITLE='Combined plots')

Thanks for your reply. It could work. But it would make the code less generic. The number of plots that I want is not necessarily 2x3 and I would like to have a general routine for it. And it is so convinent to use the INDEX keyword. ;)

Solved the problem by using object array. Pasting the plotting section of my code. Not necessarily the best solution but it works for me. oPlotArr = OBJARR(num_param*num_ang*num_mat) graphProps = {props, color:'blue', linestyle:'dashed', symbol:'triangle', thick:2} PropsArr = REPLICATE({props}, num_mat) PropsArr[0] = {color:'blue', linestyle:'dashed', symbol:'triangle', thick:2} PropsArr[1] = {color:'green', linestyle:'solid_line', symbol:'plus', thick:2} PropsArr[2] = {color:'red', linestyle:'dash dot', symbol:'X', thick:2} Yaxislabel = ['Pen / Geo', 'Sc / Geo'] win = WINDOW() FOR i = 0, num_param-1 DO BEGIN FOREACH AngleEl, Angles, Angle_indx DO BEGIN CurAngleEl = WHERE(AcceptAngle EQ AngleEl) FOREACH MatEl, Materials, Mat_indx DO BEGIN CurMatEl = WHERE(Material EQ MatEl AND AcceptAngle EQ AngleEl) CurIndx = i*num_ang*num_mat+Angle_indx*num_mat+Mat_indx OverPlotIndx = i*num_ang*num_mat+Angle_indx*num_mat IF Mat_indx EQ 0 THEN BEGIN oPlotArr(CurIndx) = PLOT(PinSizes, ResMat(i, CurMatEl), $ LAYOUT = [num_ang,num_param,(i*3+Angle_indx)+1] , /CURRENT, $ _EXTRA = PropsArr(Mat_indx), TITLE = '$\alpha$: ' + STRING(AngleEl, FORMAT='(I2.2)' ), $ YTITLE = Yaxislabel[(i*3+Angle_indx)/num_ang], XTITLE= 'Pinhole Size, mm' ) ENDIF ELSE BEGIN oPlotArr(CurIndx) = PLOT(PinSizes, ResMat(i, CurMatEl), $ LAYOUT = [num_ang,num_param,(i*3+Angle_indx)+1] , OVERPLOT = oPlotArr(OverPlotIndx), $ _EXTRA = PropsArr(Mat_indx) ) ENDELSE ENDFOREACH leg = LEGEND(TARGET=[oPlotArr(CurIndx-mat_indx+1:CurIndx)] ) FOREACH legEl, Materials, leg_indx DO leg(leg_indx).label = Materials(leg_indx) ENDFOREACH ENDFOR