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> Yuan, > One last question. > When you use netcdf to convert grib lambert_conformal projection to world, > Can you tell me how many columns X rows in your grib file and how many > columns X rows in netcdf file and also can you tell me the grid resolution? > I am close to find the solution. > Thanks, > lalitha > Hi lalitha, Did you get the solution now? Let me know if you need any more help. Yuan > -----Original Message----- > From: Unidata IDV Support [mailto:address@hidden] > Sent: Wednesday, March 23, 2011 10:54 AM > To: Lalitha Venkatramani > Cc: address@hidden > Subject: [IDV #LTA-507350]: IDV > > > Yuan, > > It is obvious that when you increase the projection to lat/lon, it will > > increase in size. > > The number of grid points will change. > > But the question is different. > > Do you maintain the same resolution ( for example in my case 10.7)of the > > native in the lat/lon projection. > > The grid dataset is in the same resolution. But the on screen image may not > be in the same resolution. > > > If so, can you please help me with a netcdf in the lat/lon projection? > > What do you want to do with a nc lat/lon projection? > > > Is there a number I can call or you may call in my cell number 405-778-9926. > > I think my email was not clear enough so that I can explain to solve my > > problem. > > > I think I still not understand your problem very well ;) > > Yuan > > > > Thanks a lot, > > Lalitha > > > > > > > > -----Original Message----- > > From: Unidata IDV Support [mailto:address@hidden] > > Sent: Tuesday, March 22, 2011 10:13 PM > > To: Lalitha Venkatramani > > Cc: address@hidden > > Subject: [IDV #LTA-507350]: IDV > > > > > > > > On Tue, 22 Mar 2011, Lalitha Venkatramani wrote: > > > > > New Client Reply: IDV > > > > > > Save the image as png. > > > You will see the number of pixels in grib and in world projection > > > When you open the image and look at properties, you will see the number > > > of pixels. > > > > > > Is your netcdf in latlon or native lc projection? > > > If it is lc, it will be identical to grib. > > > May be if you can redirect the email to the developer of this area, we > > > may have an answer. > > > > What you think about incresing the resolution is incorrected. When you > > change the projection of the display, the size of the image you saved may > > change as the area covered changed. But the resolution is still the > > same. > > > > > > Yuan > > > > Thanks, > > > Lalitha > > > > > > -----Original Message----- > > > From: Unidata IDV Support [mailto:address@hidden] > > > Sent: Tuesday, March 22, 2011 6:19 PM > > > To: Lalitha Venkatramani > > > Cc: address@hidden > > > Subject: [IDV #LTA-507350]: IDV > > > > > > > > > > > > On Tue, 22 Mar 2011, Lalitha Venkatramani wrote: > > > > > > > New Client Reply: IDV > > > > > > > > Ok, IDV image looks great. That is the reason I am trying to understand > > > > the projection. > > > > > > > > As I explained in my email, > > > > minimum lat is 13.8992 > > > > maximum lat is 65.3821 > > > > minimum lon is -144.517 > > > > maximum lon is 41.9596 > > > > > > > > Rows, columns, xres and yres ( xres and yres in meters)of the lambert > > > > conformal projection:480 576 10700 10700 > > > > > Resolution in lambert conformal is 10700 meters. When I display using > > > > > IDV, I get the image with properties set to 576 X 480 pixels. > > > > > > > > If you convert the lambert projection to latlon , FOR THE SAME > > > > RESOLUTION 10.7 km, Latitude points are roughly, > > > > > > > > Latitude spans 52 degrees > > > > 1 degree is 100 km. so, roughly 520 points for a 10 km resolution > > > > > > > > Latitude spans = 103 degrees roughly - s0, 1030 grid points for a 10 km > > > > resolution. > > > > > > > > When I convert the original grib file to projections/predefined/world > > > > in IDV and display in lat/lon projection. > > > I see IDV shows 1203 x 918 points and the image looks great. > > > > > > > > > > > > > > I did the same convertion as you, but I am not sure how do you > > > see how many points in the IDV display. What I did is to export the > > > display image > > > to the nc file, and then I can tell the same number of points in both > > > projection. > > > > > > > > > Yuan > > > > You may notice, I use 10 km resolution which is the resolution in the > > > > grib file. > > > > > > > > So, I am just interested to know if you use the same resolution. > > > > Can you please tell me how do you convert lambert to world? > > > > > > > > I see your source code, but I could not locate that area yet. > > > > > > > > > > > > Thanks a lot, > > > > Lalitha > > > > > > > > -----Original Message----- > > > > From: Lalitha Venkatramani > > > > Sent: Tuesday, March 22, 2011 5:51 PM > > > > To: 'address@hidden' > > > > Subject: RE: [IDV #LTA-507350]: IDV > > > > > > > > Ok, IDV image looks great. That is the reason I am trying to understand > > > > the projection. > > > > > > > > As I explained in my email , > > > > minimum lat is 13.8992 > > > > maximum lat is 65.3821 > > > > minimum lon is -144.517 > > > > maximum lon is 41.9596 > > > > > > > > Rows, columns, xres and yres ( xres and yres in meters)of the lambert > > > > conformal projection:480 576 10700 10700 > > > > > Resolution in lambert conformal is 10700 meters. When I display using > > > > > IDV, I get the image with properties set to 576 X 480 pixels. > > > > > > > > If you convert the lambert projection to latlon , FOR THE SAME > > > > RESOLUTION 10.7 km, > > > > Latitude points are roughtly, > > > > > > > > Latitude spans 52 degrees > > > > 1 degree is 100 km. so, roughly 520 points for a 10 km resolution > > > > > > > > Latitude spans = 103 degrees roughly - s0, 1030 grid points for a 10 km > > > > resolution. > > > > > > > > When I convert the original grib file to projectons/predefined/world > > > > in IDV and display in lat/lon projection. I see IDV shows 1203 x 918 > > > > points and the image looks great. > > > > > > > > > > > > You may notice, I use 10 km resolution which is the resolution in the > > > > grib file. > > > > > > > > So, I am just interested to know if you use the same resolution. > > > > Can you please tell em how do you convert lambert to world? > > > > > > > > I see your source code, but I could not locate that area yet. > > > > > > > > > > > > Thanks a lot, > > > > Lalitha > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -----Original Message----- > > > > From: Unidata IDV Support [mailto:address@hidden] > > > > Sent: Tuesday, March 22, 2011 11:53 AM > > > > To: Lalitha Venkatramani > > > > Cc: address@hidden > > > > Subject: [IDV #LTA-507350]: IDV > > > > > > > > > Dear Support, > > > > > I have a grib file with > > > > > Min/Max Lat/Lon 13.8992 -144.517 65.3821 -41.9596 > > > > > Rows, columns, xres and yres ( xres and yres in meters)of the lambert > > > > > conformal projection:480 576 10700 10700 > > > > > Resolution in lambert conformal is 10700 meters. When I display using > > > > > IDV, I get the image with properties set to 576 X 480 pixels. > > > > > > > > > > I use projectons/predefined/world in IDV and display in lat/lon > > > > > projection. > > > > > I see for the converted image ( 1203 X918) pixels. > > > > > > > > > > If the native resolution 10.7 km ( roughly 0.1 degree is maintained, > > > > > I am wondering how we get 1203 X918 pixels. > > > > > > > > > > Thanks, > > > > > Lalitha > > > > > > > > > I loaded an image and changed the projection, I didn't see any > > > > resolution change, can you give me more detail information of what you > > > > were doing? > > > > > > > > > > > > Yuan > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -----Original Message----- > > > > > From: Unidata IDV Support [mailto:address@hidden] > > > > > Sent: Tuesday, March 22, 2011 10:55 AM > > > > > To: Lalitha Venkatramani > > > > > Cc: address@hidden > > > > > Subject: [IDV #LTA-507350]: IDV > > > > > > > > > > > Dear Support, > > > > > > > > > > > > I am using IDV to display grib files. > > > > > > > > > > > > When I convert lambert to Latlon using projectons/predefined/world, > > > > > > I get > > > > > > lat/lon projection. > > > > > > > > > > > > Do you maintain the native resolution in this conversion? > > > > > > > > > > > > I can send my file and discuss more when I hear from you? > > > > > > > > > > > > Thanks, > > > > > > Lalitha > > > > > > > > > > > > > > > > Hi Lalitha, > > > > > I don't think the resolution being changed in this conversion. > > > > > > > > > > > > > > > Yuan > > > > > > > > > > > > > > > > > > > > > Ticket Details > > > > > =================== > > > > > Ticket ID: LTA-507350 > > > > > Department: Support IDV > > > > > Priority: Normal > > > > > Status: Closed > > > > > > > > > > > > > > > > > > > > > > Ticket Details > > > > =================== > > > > Ticket ID: LTA-507350 > > > > Department: Support IDV > > > > Priority: Normal > > > > Status: Open > > > > > > > > > > > > > > > > Ticket Details > > > > =================== > > > > Ticket ID: LTA-507350 > > > > Department: Support IDV > > > > Priority: Normal > > > > Status: Open > > > > Link: > > > > https://www.unidata.ucar.edu/esupport/staff/index.php?_m=tickets&_a=viewticket&ticketid=12991 > > > > > > > > > > > > > > > > Ticket Details > > > =================== > > > Ticket ID: LTA-507350 > > > Department: Support IDV > > > Priority: Normal > > > Status: Open > > > > > > > > > > > > Ticket Details > > > =================== > > > Ticket ID: LTA-507350 > > > Department: Support IDV > > > Priority: Normal > > > Status: Open > > > Link: > > > https://www.unidata.ucar.edu/esupport/staff/index.php?_m=tickets&_a=viewticket&ticketid=12991 > > > > > > > > > > > Ticket Details > > =================== > > Ticket ID: LTA-507350 > > Department: Support IDV > > Priority: Normal > > Status: Open > > > > > > > Ticket Details > =================== > Ticket ID: LTA-507350 > Department: Support IDV > Priority: Normal > Status: Open > > Ticket Details =================== Ticket ID: LTA-507350 Department: Support IDV Priority: Urgent Status: Closed