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Hi Nick, re: code in kbxwari.dlm > thanks. i was working on that when you wrote. Great minds think alike ;-) re: > i wrote a simple byte reader, and think i can get the calibration information > now. > it looks, though, like the byte indexing in the area file may be off by 1 for > the calibation file … > it is suppose to start at 768, but looks like it starts at 769. This is likely to be an interpretation of 1 vs 0 indexing. The byte offset of 768 assumes that the first byte is byte 0, not byte 1. > >> read_area_block('D262_B4', 769) I assume that this is in your Matlab code... > FILE: D262_B4.AREA > BIDX: 772 771 770 769 > BIN#: 01010111 01000001 01010010 01001001 > DEC#: 87 65 82 73 > ASCI: W A R I > INT32: 1463898697 re: > the documentation also seems to say i am able to use DSSERVE to copy a > Hamawari Data File directly from the SSEC server to my machine, but … I have > not figured out how to do that yet, so i will keep working with the area file. This is not the case. All ADDE transfers use a synthesized AREA format. ADDE does not provide access to the original file. re: > the calibration coefficients are multipied by 1,000,000 to convert from > int64’s to int32’s. The calibration coefficients are multiplied by 10**-7, not 10**7. re: > the pixel ‘count’ data (data block) does not have any conversions, so i think > i just > need to divide the cal coeffiectns by 1,000,000 then multiply by the data > block values. > do you think that is correct? The code in kbxwari.dlm multiplies the values store in the calibration block by 10**-7. NB: all header values in an AREA file are 4-byte integers re: > thanks again for the help. i am pretty close now. No worries, and I think that you are correct, you are close. re: > thanks again, if i am reading our code snipped correctly, > i guess i do not need to divide by 1,000,000 for the cal coefficients. See above. re: > i am still a little puzzled by the data type. i think each block is 4 bytes. Correct. re: > however, cal_blocks 8-17 seem to indicate they are ‘doubles (DBLE?)’ No, kbxwari.dlm converts them to doubles. re: > when i read off these 4 bytes should i try to read them as: > int 32’s (4 bytes) Yes. re: > singles (floating point 4 bytes) (double in ‘c’ is 8 bytes?) > or another data type? No, all AREA file header words are 4-byte integers. re: > thanks No worries. Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: SKX-144523 Department: Support McIDAS Priority: Normal Status: Closed