Dear Daikan, I have done the following, and it seems to work fine. I have simple run the code, and then set new data: xx=1.5*x yy=1.5*y uu=.2*u vv=.2*v vect.setdata, uu, vv, xx, yy And the results seem correct. What kind of new data are you using? Let me know if I'm missing something. Thank you. Cheers, Fernando Exelis VIS

Fernando: I implented the fellowing code, but has the same problem. I use IDL 8.1 with windows7. IDL> ; Read the data. IDL> RESTORE, FILEPATH('globalwinds.dat', SUBDIR=['examples','data']) IDL> IDL> ; Set up the map projection, grid, and continents. IDL> mapimage = MAP('Equirectangular', LIMIT=[0,-180,89,-30]) IDL> cont = MAPCONTINENTS(/CURRENT) IDL> IDL> ; Display the vector data on top of the map. IDL> vect = VECTOR(u, v, x, y, /OVERPLOT, RGB_TABLE=39, AUTO_COLOR=1) % Loaded DLM: XML. % Loaded DLM: SHAPEFILE. % Program caused arithmetic error: Floating divide by 0 % Program caused arithmetic error: Floating illegal operand % Program caused arithmetic error: Floating divide by 0 % Program caused arithmetic error: Floating illegal operand % Loaded DLM: PNG. IDL> xx=1.5*x IDL> yy=1.5*y IDL> IDL> uu=.2*u IDL> vv=.2*v IDL> vect.setdata, uu, vv, xx, yy ps: When I use new graphics function, I always get error: % Program caused arithmetic error: Floating divide by 0 % Program caused arithmetic error: Floating illegal operand

Hi there, I understand now from your first message that you did the following: 1- execute the example code. 2- move or zoom in the map window with the mouse 3- type: vect.setdata, u, v, x, y 4- the map goes back to the original view. If those where the steps you made, then, it is the normal behaviour since the values of the variables (u, v, x, y) still contain the same values, they have not changed since you executed: vect = VECTOR(u, v, x, y, /OVERPLOT, RGB_TABLE=39, AUTO_COLOR=1) That's why it goes back to the original view. Let me now understand the error message that you are seeing. I will be back as soon as possible. Cheers, Fernando After using the mouse

Hi Daikan, I apologize, I think I misunderstood again. Yes, I agree that I would expect to have the view of the window (after zooming or panning) to stay the same after re-setting certain vector values. I will try to understand if this is an expected behavior or not from the point of view of engineering. About the error message that you see, they seem to happen only in Windows 7. One workaround is to change to Software Rendering mode. You can do that by going to Window --> Preferences. Then, click in the (+) sign next to IDL. In there you will find the place to change to Software Rendering. Apply the changes and try the graphic functions again. They should work fine. Cheers, Fernando

Hi fernandos, Very thanks for your reply. I wish IDL can provide an option for keeping the view of window. I try the software render and it's useful. But I think the error message with device render does not effect the final graphics . I'll keep device render for fast speed. thanks again. daikan

Hi Daikan, Ok, I found that the behavior is expected in a way. Because there is a way around the re-scaling: 1- Run the example code: RESTORE, FILEPATH('globalwinds.dat', SUBDIR=['examples','data']) mapimage = MAP('Equirectangular', LIMIT=[0,-180,89,-30]) cont = MAPCONTINENTS(/CURRENT) vect = VECTOR(u, v, x, y, /OVERPLOT, RGB_TABLE=39, AUTO_COLOR=1) 2- Change the image plot by, for example, zooming into a particular area 3- Run the following command: oldxrange=mapimage.XRANGE & oldyrange=mapimage.YRANGE 4- And now change the data in this way: vect.setdata, u*1.5, v*1.5, x*1.5, y*1.5 & mapimage.XRANGE=oldxrange & mapimage.YRANGE=oldyrange Then, the scale of the image plot will stay the same as after the zoom. Cheers, Fernando