Changes between Initial Version and Version 1 of Processing/Wavelengths

Timestamp:

Mar 4, 2008, 6:01:27 PM (17 years ago)

Author:

mggr

Comment:

--

Processing/Wavelengths

@@ +1 @@
+You can get the bandwidth information from an HDF files by running azexhdf on it.  The information is stored in several vectors in the HDF.  For CCD sensors, the key vectors are:
+ * CAwavc: wavelength central frequencies for CCD sensors (CASI, Eagle, Hawk), in nm
+ * CAwavh: wavelength half bandwidth for CCD sensors (CASI, Eagle, Hawk), in nm
+
+The length of the vectors will vary for CCD sensors depending on the band configuration.
+
+For ATM,
+ * ATwavu & ATwavl: upper and lower wavelength limits for ATM, in nm
+
+The ATM vectors will never vary.
+
+== Example commands ==
+
+General form: `azexhdf -vf OUTPUT_FILE.txt -vn VECTOR_NAME -h LEV1_HDF_FILENAME`
+
+`azexhdf -vf casi192_wave_centre.txt -vn CAwavc -h lev1/c192a011b.hdf `
+ * this prints lots of information and also outputs the vector as space-separated numbers to the file, e.g.
+{{{
+ 408.94 440.93 488.94 508.72 528.52 559.66 570.06 588.97 620.21 648.68 670.55 679.11 684.83 704.86 754.62 779.60 871.54
+}}}
+
+A unix command to transpose this output into a column is `cat OUTPUT_FILE.txt | tr ' ' \\n > OUTPUT_FILE-transposed.txt`
+
+Band Center-Wavelength Half-bandwidth
+ 1    408.94            6.74479
+ 2    439.04            6.74581
+ 3    487.99            6.75106
+ 4    507.78            7.69685
+ 5    557.78            6.76623
+ 6    617.37            7.73400
+ 7    661.99            6.80551
+ 8    678.16            5.86114
+ 9    705.81            6.82787
+10    748.86            3.97656
+11    757.50            3.01953
+12    775.75            9.75582
+13    862.78           11.79800
+14    882.26            5.97619