ratiocs Documentation

ratiocs - Compute ratio of cube and spectrum from a table file
"ratiocs" will divide every spectrum in a cube by a spectrum read from
an average spectrum TABLE file using the following equation:

        OUTCUBE = ((INCUBE+ADDT)/(SPEC+ADDB)) * MUL

where:
        OUTCUBE = each result spectrum
        INCUBE  = each input spectrum of the cube
        SPEC    = the constant spectrum read from the table file
        ADDT    = a constant added to INCUBE
        ADDB    = a constant added to SPEC
        MUL    = a multiplicative constant

Also, the divisor spectrum will be inserted into the lower right
corner of the output image cube, i.e., at the spatial location
corresponding to the maximum sample number and maximum line number.
This spectrum will be normalized so that its average value is the
same as the value specified for the MUL parameter.  (Zero values and
special pixel values in the divisor spectrum are not used in computing
the normalization factor.)

The divisor spectrum table file can contain an average spectrum that
was computed by the "cubespec" program or by one of the average
spectrum functions in the CV display program (either the rectangular
box average or the arbitrary Region of Interest average).  Also, any
other suitable table file can be used as the source of the divisor
spectrum.  The only requirements are that it contain an INTEGER*4
column named BAND and a REAL*4 column named AVERAGE.  The BAND column
records the input file band number that was used in computing each
element of the average spectrum.

The wavelength bands in the output file will include the same bands
that are selected by the input subcube specifier.  It is not necessary
for this list of bands to contain the same bands that are contained
in the divisor spectrum.  "ratiocs" will match the input cube file band
numbers with the corresponding file band numbers in the divisor
spectrum.  If a cube file band number is not contained in the divisor
spectrum, then all the pixels in that band number will be set to NULL.
(Band numbers in the divisor spectrum that are not included in the
cube file will just be ignored.)

If a value in the divisor spectrum is zero or a special pixel value,
then all the pixels in the corresponding output cube file band will be
set to NULL.  The same action will occur if a non-zero divisor
spectrum value plus its additive factor ADDB results in a zero value.
If an input cube file pixel is the NULL value or any type of
saturation value, then the corresponding output value is set to NULL.

Input suffix data that are selected by the input subcube specifier will
be propagated unchanged to the output file.

Programmer: Jim Torson - U.S.G.S., Flagstaff, AZ

Input cube file name
  (default extension is .cub)

NONE

Input subcube specifier

--

Output cube name
  (default extension is .cub)

NONE

Divisor spectrum file name
  (default extension is .tbl)

NONE

Spectrum table object name
  (default is TABLE)

"TABLE"

Constant to add to cube

0.0

Constant to add to spectrum

0.0

Constant to multiply

1.0

Output pixel type
 NULL = input type
    1 = 8 bit
    2 = 16 bit
    3 = 32 bit

--

Output min/max data range

NONE

User comment

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ADDITIONAL NOTES:

Parm	Description
FROM	Input cube file name. If the file extension is omitted, then ".cub" will be assumed.
SFROM	SFROM specifies the subcube using a single string for all three dimensions of the cube. The order of the three dimensions is always "samples:lines:bands". If a dimension is left blank, all the data for that dimension is selected. The default value of NULL for SFROM selects the entire cube. Any application below can be used for any dimension. To select specific data from any dimension: "10-100(3):11,12,15-20:1-10(2)" = This example will select every third sample starting with sample 10 thru 100. It selects lines 11 and 12, and 15-20. It selects every other band, starting with band 1 thru 10. There are special characters that can be used for selecting a subcube efficiently, such as "*","#", and "~". For examples type "help sfrom" in TAE. **NOTE** For more examples and explanation of the many features of the SFROM parameter, tutor the sfrom.pdf or refer to Introduction To ISIS, Section 6, of the ISIS User's Manual ** If processed data are being written back into the input file, then this parameter must select the entire core of the input file.
TO	Output cube file name. If the file extension is omitted, then ".cub" will be assumed.
TBLFROM	Name of the table file that contains the divisor spectrum. If no file extension is specified, then ".tbl" will be assumed. This table file can be produced by the "cubespec" program or by one of the average spectrum functions of the CV display program (either the rectangular box average or the arbitrary Region of Interest average).
OBJNAM	Name of the table object in the TBLFROM file that contains the divisor spectrum. If a NULL value (all blanks) is specified, then "TABLE" will be assumed.
ADDT	Additive factor that is added to the "top" of the ratio, i.e., the values from the input cube file.
ADDB	Additive factor that is added to the "bottom" of the ratio, i.e., the values from the divisor spectrum table file.
MUL	Multiplicative factor by which the ratio is multiplied. MUL also specifies the normalization of the divisor spectrum when it is inserted into the lower right corner of the output cube file. Each value in the spectrum is multiplied by a factor that will result in the average spectrum value being equal to MUL.
OTYPE	Output pixel data type. Permitted values are: NULL - output type is same as input file pixel type 1 - 8-bit (integer with type conversion parameters) 2 - 16-bit (integer with type conversion parameters) 3 - 32-bit (floating point) When processed data are being written back into the input file, the output pixel type must be the same as the existing pixel type in the input file.
ORANGE	Output pixel data range. If ORANGE is NULL, then the CORE_BASE and CORE_MULTIPLIER in the output file will be set to represent the same range of data as the input file. If OTYPE=1 (8-bit) or OTYPE=2 (16-bit), then the CORE_BASE and CORE_MULTIPLIER in the output file will be set to values that allow representing the specified range of output values. Output values outside this range will be stored as a special "representation saturation" value. The ORANGE parameter is ignored if OTYPE=3 (32-bit) since the CORE_BASE and CORE_MULTIPLIER are not applicable to floating point pixel values. **NOTE** For a more detailed explanation of ORANGE, tutor the orange.pdf.
USERNOTE	Comment from the user. This will be recorded in the ISIS session log file and also in the History entry that is put into the History object of the output cube file.