Initial commit

1 files changed, 94 insertions, 0 deletions

diff --git a/noao/onedspec/irsiids/doc/flatdiv.hlp b/noao/onedspec/irsiids/doc/flatdiv.hlp
new file mode 100644
index 00000000..e6e8c22e
--- /dev/null
+++ b/noao/onedspec/irsiids/doc/flatdiv.hlp
@@ -0,0 +1,94 @@
+.help flatdiv Dec86 noao.imred.iids/noao.imred.irs
+.ih
+NAME
+flatdiv -- Divide spectra by flat field spectra
+.ih
+USAGE
+flatdiv input records
+.ih
+PARAMETERS
+.ls input
+The root file name for the input records to be divided.
+.le
+.ls records
+The range of spectra to be included in the divide operation.
+Each range item will be appended to the root name to form an
+image file name.
+.le
+.ls output
+New spectra are created by the flatdiv operation. This parameter
+specifies the root name to be used for the created spectra.
+.le
+.ls start_rec
+Each new spectrum created as "output" has its root name and a 
+trailing number appended starting with "start_rec". Subsequent
+output images will have an incremented trailing number.
+Note that even if an output image is not created because the input
+image has already been flattened or the input image is not found the
+output record number is still incremented.
+.le
+.ls flat_file
+The root name for the sensitivity spectra as produced by FLATFIT.
+Normally with multi-aperture instruments, FLATFIT will produce a
+spectrum appropriate to each aperture and the file name will have
+"flat_file" as the file name root and the aperture number appended.
+.le
+.ls coincor = )_.coincor
+If set to yes, coincidence correction is applied to the data during
+the division, and the following three parameters are required.
+For more about this correction see \fBcoincor\fR.
+.ls ccmode = )_.ccmode
+The mode by which the coincidence correction is to be performed.
+This may be "iids" or "photo".
+.le
+.ls deadtime = )_.deadtime
+The detector deadtime in seconds.
+.le
+.ls power = )_.power
+Power law IIDS non-linear correction exponent.
+.le
+.le
+.ih
+DESCRIPTION
+The input spectra are divided by the flat fields which are
+represented by spectra produced by FLATFIT.
+
+To avoid possible division by zero, any zeroes in the flat field
+spectra generated by FLATFIT are replaced by 1.0.
+
+The input spectra may optionally be corrected for coincidence losses.
+
+If the input and output spectra (after appending the record numbers) are
+the same then the division is performed in-place; i.e. the flattened spectra
+replace the original input spectra.
+Note that even if an output image is not created because the input
+image has already been flattened or the input image is not found the
+output record number is still incremented.  This is to insure that if
+in-place division is desired that the input and output names remain
+matched.
+.ih
+EXAMPLES
+The following example divides a series of spectra to produce 20 new
+spectra having names nite1.1221 ... nite1.1240.
+
+	cl> flatdiv nite1 1201-1220 nite1 1221
+
+The same spectra as above are simultaneously corrected for
+coincidence losses.
+
+	cl> flatdiv nite1 1201-1220 nite1 1221 coincor=yes
+
+The flattened spectra replace the unflattened spectra.
+
+	cl> flatdiv nite1 1201-1220 nite1 1201
+
+Note that the input record numbers must be contiguous and the starting
+output record number must be the same as the first input record number.
+.ih
+TIME REQUIREMENTS
+Approximately 1 second is required to correct a spectrum of length
+1024 points.
+.ih
+SEE ALSO
+coincor, flatfit
+.endhelp