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>From: Jason Levit <address@hidden> >Organization: Center for Analysis and Prediction of Storms, University of >Oklahoma >Keywords: 200110222135.f9MLZn102781 McIDAS-X ADDE GINI AREA Jason, re: selecting remap targets > Ok, this make sense. I'm assuming we have to carefully select a good >image, because the GVAR nav data changes from image to image? Yes, sort of. Selecting a well navigated target cuts down on one source of error in the remap. > Actually, we were trying to read data from a McIDAS AREA format that >contained TANC information. This was done after the re-mapping from >GINI to McIDAS AREA. The process of doing an IMGCOPY from one dataset to another does not remap the image. It simply copies it. Perhaps we are misunderstanding each other because we are not viewing the various operations the same. Remapping in McIDAS is the process of converting one projection to another. an IMGCOPY from a GINI dataset to an AREA dataset does not do anything with the navigation information other than reformulate it to fit the symantics of the destination dataset. An IMGREMAP, on the other hand, can change the navigation. > Is it possible that we're talking about two different kinds of GINI data? No. >The GINI data I'm using is directly from the NOAAPort feed, and has not >been through McIDAS yet. The GINI data that I demonstrated access to in my last email is identical to what you are receiving in your NOAAPORT ingest system. The reason for this is that we are receiving the data through our NOAAPORT ingest system. The only thing that was done in McIDAS was the writing of an ADDE server that understands the format of the GINI data. This then allows one to use all of the existing McIDAS tools (and they are considerable) to display/analyze/copy/remap the GINI data. >Are you talking about GINI data that is contained >in McIDAS AREA format? No. The GINI imagery served are in their original format, just like the ones on your system. >I'm probably just confused (happens often). I am sure that it is just the newness of working with McIDAS. An opinion of mine developed over time is that a lot of people simply don't "get" McIDAS at first. After working with it, however, people usually discover just how powerful it can be in their research activities. This opinion was borne out by observing just how many people included McIDAS display output in their talks at the recently held AMS Conference on Satellite Meteorology. re: which commands were you using > Sure, here's the commands I used: > > imgcopy.k GINICAPS/AREA MYDATA/IMAGES.1000 SIZE=ALL > > (GINICAPS/AREA contains a McIDAS AREA file we received from SPC) > > imgremap.k GINICAPS/GINI MYDATA/IMAGES.1000 > > (GINICAPS/GINI contains a raw GINI file we received through NOAAPort) In the above, there was no effort made to specify the type of image being copied or remapped. By type, I mean the originating satellite platform (e.g., GOES-East or GOES-West), or band (e.g., 0.65 um visible, 3.9 um infrared, 6.8 um water vapor, 10.7 um infrared, or 12.0 um infrared). So, if ALL of the images you get from SPC are in GINICAPS/AREA and ALL of the GINI images you get from NOAAPORT are in GINICAPS/GINI, then the images that will be used in the commands above will be variable. One time the input SPC image could be a VIS (0.65 um) another time it could be a WV (6.8 um), etc. The same comment holds true for the GINI images. I strongly suggest that you setup more specific datasets for both sets of images. What I have in mind is a clearer separation of images by originating platform and band. The example I sent you last night demonstarted what I have in mind. For instance, GINIALL/GE4KIR - the set of all GOES-East 4 km IR (10.7 um) images in the ADDE group GINIALL GINIALL/GW1kVIS - the set of all GOES-West 1 km VIS (0.65 um) images in the ADDE group GINIALL, etc The reason for the GINIALL group on adde.ucar.edu is that we keep 15 days of GINI images online at all times. The images for "today" (where "today" is the current day from 0Z until 23:59:59Z) are split into three ADDE datasets: GINICOMP, GINIEAST, and GINIWEST. This is simply an organizational construct. If we are talking about current day images, then the following equivalences are true: GINIALL/GW1KVIS <-> GINIWEST/GW1KVIS GINIALL/GE4KIR <-> GINIEAST/GE4KIF etc. Splitting the full set of GINI images into three datasets allows the end user to "point" at different servers (point meaning 'DATALOC ADD GINIEAST xxx', 'DATALOC ADD GINIWEST yyy', etc.) to get their data. This spreads the data request around to different servers. Shares the "wealth" (service) as it were. I would be most happy to help you setup your ADDE datasets into logical partitions of the data. This could be done very quickly, and it would get you on your way. Please let me know if you are interested. > Results after imgremap.k command: > > imgremap.k: The portion of the image requested does not exist > imgremap.k: Failed to open source image for read This is because you were probably trying to remap a GINI image from GOES-West into an SPC image from GOES-East. In fact, it could be the case that the GINI image tried in the remap was one over Hawaii and the destination was over the Eastern US. Since there are no overlaps in data points between the two, IMGREMAP will tell you so (the portion of the image does not exist) and exit. re: CAPS has existing code to convert a GVAR navigated ... >Our code currently reads the McIDAS AREA files, converts the data into >albedo, then is read into a cloud analysis scheme an the numerical model. OK. >I was noticing this yesterday as well, that it appears we could create >the model grid in McIDAS, and re-map the satellite data into the model >grid. Satellite data can be sampled into a model grid, yes (I want to get away from the use of re-map since it is not actually what is going on). >If that data could be made into a netCDF file, then all we'd need >to do is write a little routine to read the netCDF file, and we could bypass >a lot of the infrastructure we describe here. Hmm... McIDAS has an ADDE output image server that can write image data into a netCDF, but it does not have an ADDE output grid server that can write into a netCDF. It has the input netCDF server, but that is not exactly what you are looking for. The work necessary to write a McIDAS grid into an output netCDF wouldn't be too much, so the project is not a large one. >Again, I really appreciate all of your patience and help. You're helping >to answer questions that have plagued us for years, and we've had a hard >time tracking down documentation. Thanks a million - really! Hopefully, the trials in tracking down documentation are not McIDAS related. All McIDAS documentation is online and viewable by anyone (open standards). TeraScan data, on the other hand, is not well documented. > I'll work through the example you mentioned when I get to work (I'm at >my Windows machine at home) and let you know how it goes. Fair enough. Again, I am willing to setup your ADDE datasets for SPC and GINI data so that you don't keep running into remap errors like the one you describe above. Please let me know if _anything_ I have tried to explain is not clear enough. Once you understand the McIDAS setup, I think you will see that the package can provide you with a set of tools that will make your work easier, not harder. Tom >From address@hidden Fri Oct 26 10:19:09 2001 >Subject: Re: 20011026: 20011025: GINI conversion to AREA (cont.) re: specific setup for datasetx Acutally, the GINICAPS/AREA and GINICAPS/GINI only contain each one file right now for testing, and both are GOES-08 images. Here's my lines in "CAPSGINI.BAT": DSSERVE ADD GINICAPS/GINI GINI TYPE=IMAGE DIRFILE=/work/cube/test/gini/ *.vis "JASON TEST DSSERVE ADD GINICAPS/AREA AREA TYPE=IMAGE DIRFILE=/work/cube/test/area/ goes08vis_* "JASON TEST re: offer of help setting up datasets We certainly welcome any help we can get. I'll talk about this with Kevin Thomas (he's the new data ingest guru) once we're done testing all of this out. I'm sure he'd appreciate insight! Let's make sure we can get this working before taking on the set-up, if that's ok. I agree with you about setting up different data sets, and we'll certainly do this with you once we get operational and real-time. re: images were probably of a different type That makes sense, though both images are GOES-08. Here's their information: mcidas@cube$ imglist.k GINICAPS/GINI FORM=EXP Image file directory listing for:GINICAPS/GINI Pos Satellite/ Date Time Center Res (km) Image_Size sensor Lat Lon Lat Lon --- ------------- ------------ -------- ---- ---- ----- ----- ------------ 1 G-8 IMG 25 OCT 01298 16:45:00 41 88 Band: 1 0.65 um Visible - Cloud Cover 1.0 1.0 5120 x 5120 proj: 0 created: 2001298 194011 memo: GINI:: Sat 11 SecID 1 ChID 1 type:VISR cal type:BRIT offsets: data= 768 navigation= 256 calibration= 0 auxillary= 0 doc length: 0 cal length: 0 lev length: 0 PREFIX= 0 valcod: 0 zcor: 0 avg-smp: N start yyddd: 2001298 start time:164500 start scan: 0 lcor: 1 ecor: 1 bytes per pixel: 1 ss: 70 Image Center Point Res (derived) Lat: 0.98 (km) Lon: 0.98 (km) mcidas@cube$ imglist.k GINICAPS/AREA FORM=EXP Image file directory listing for:GINICAPS/AREA Pos Satellite/ Date Time Center Res (km) Image_Size sensor Lat Lon Lat Lon --- ------------- ------------ -------- ---- ---- ----- ----- ------------ 1 G-8 IMG 25 OCT 01298 17:02:00 36 96 Band: 1 0.65 um Visible - Cloud Cover 1.0 2.0 2800 x 4200 proj: 0 created: 2001298 171330 memo: RT GVAR type:VISR cal type:BRIT offsets: data= 2816 navigation= 256 calibration= 0 auxillary= 0 doc length: 0 cal length: 0 lev length: 0 PREFIX= 0 valcod: 0 zcor: 0 avg-smp: N start yyddd: 2001298 start time:170142 start scan: 372 lcor: 3060 ecor: 8061 bytes per pixel: 1 ss: 70 Image Center Point Res (derived) Lat: 1.47 (km) Lon: 1.33 (km) imglist.k: done re: trials in tracking down documentation Yes, you are correct, it's actual documentation about the numbers in the files, and not McIDAS. After some searching on the web, we've finally found some documents that describe the formats. Basically, it's finding documentation on the mathematics of the orbits, etc., so we can correctly re-map the data to the numerical model grid that drove us nuts ("Gould" number info and how to use it was weird). re: were explanations not clear enough Your explanations have been extremely clear. Thanks again. As you say, once I get past the learning curve I'm sure I'll be using McIDAS a whole lot more...I love it's display system! Jason ---------------------------------------------------------------------------- Jason J. Levit, N9MLA Research Scientist, address@hidden Center for Analysis and Prediction of Storms Room 1022 University of Oklahoma 405/325-3503 http://www.caps.ou.edu/