1 files changed, 142 insertions, 0 deletions
diff --git a/noao/rv/prepspec.x b/noao/rv/prepspec.x
new file mode 100644
index 00000000..e309e692
--- /dev/null
+++ b/noao/rv/prepspec.x
@@ -0,0 +1,142 @@
+include <math.h>
+include "rvpackage.h"
+include "rvflags.h"
+include "rvsample.h"
+
+# PREP_SPEC - Prepare the input spectra prior to a Fourier transform.  Data
+# are centered in the transform array according to the number of points covered
+# by both spectra.  Apply the DC bias and the cosine bell.
+
+procedure prep_spec (rv, ssp, npts, fftnpts, datanpts, data, tform, ishift, 
+    apodize)
+
+pointer	rv				#I RV struct pointer
+pointer	ssp				#I Sample struct pointer
+int	npts				#I npts in global data array
+int	fftnpts				#I Output size of prepared array
+int	datanpts			#I npts in original data array
+pointer	data				#I pointer to original temp space
+pointer	tform				#I Prepared transform work space
+int	ishift				#I Shift of spectrum
+int	apodize				#I Apodize the data?
+
+pointer sp, tp
+int	i, iremain, num
+real	dc, rv_avgpix()
+
+define	FORWARD			-1
+
+begin
+	call smark (sp)
+	call salloc (tp, fftnpts, TY_REAL)
+
+	# Do some error checking.
+	if (data == NULL || tform == NULL) 
+	    call error (0, "NULL pointer passed to prep_spec()")
+	else if (ishift < 0)
+	    call error (0, "Negative shift found preparing spectrum.")
+
+	if (DEBUG(rv)) {
+	    call d_printf (DBG_FD(rv), "prep_spec:\t")
+	    call d_printf (DBG_FD(rv), "ishift=%d np=%d dnp=%d fnp=%d\n")
+		call pargi (ishift); call pargi(npts)
+		call pargi (datanpts); call pargi(fftnpts)
+	}
+
+	# Get things started.
+	call aclrr (Memr[tform], fftnpts)
+	#call amovr (Memr[data], Memr[tform+ishift], npts)
+	call amovr (Memr[data], Memr[tform+ishift], datanpts)
+
+	# Generate size dependent parameters.
+	if (SR_COUNT(ssp) != ALL_SPECTRUM && apodize == YES) {
+	    #call prep_samples (rv, ssp, Memr[tform+ishift], npts, apodize)
+	    call prep_samples (rv, ssp, Memr[tform], npts, apodize)
+	} else {
+	    num = datanpts
+	    if (apodize == YES) {
+	        call fft_cosbel (Memr[tform+ishift], num, FORWARD, 
+		    RV_APODIZE(rv))
+	    }
+	}
+
+	# Center the data in the transform arrays.
+	if (fftnpts != npts) {
+	    call aclrr (Memr[tp], fftnpts)
+	    call amovr (Memr[tform], Memr[tp], npts)
+	    call aclrr (Memr[tform], fftnpts)
+	    iremain = (fftnpts-npts) / 2
+	    do i = 1,npts 				# get centered
+	        Memr[tform+iremain+i-1] = Memr[tp+i-1]
+	} else
+	    iremain = 0
+
+	# Now compute the bias to raise zero level to spectrum mean.
+	dc = rv_avgpix (Memr[tform], fftnpts)		  # compute DC level
+	call asubkr (Memr[tform], dc, Memr[tform], fftnpts) # apply DC bias
+
+	call sfree (sp)
+end
+
+
+# PREP_SAMPLES - Prepare the data by masking according to the samples and
+# apodizing each region.
+
+procedure prep_samples (rv, ssp, data, npts, apodize)
+
+pointer	rv					#I RV struct pointer
+pointer	ssp					#I Sample struct pointer
+real	data[ARB]				#U Data array
+int	npts					#I Npts in array
+int	apodize					#I Apodize the data?
+
+int	i, j, k, np, left, right
+
+begin
+	left = 1
+	if (SR_UNITS(ssp) == PIXELS) {
+	    #right = nint (SRANGE(ssp,1) - RV_GLOB_W1(rv) + 1)
+	    right = SRANGE(ssp,1) - RV_GLOB_W1(rv) + 1
+	} else {
+	    right = nint ((log10(SRANGE(ssp,1)) - RV_GLOB_W1(rv)) / 
+		RV_OWPC(rv)) + 1
+	}
+	do i = 1, SR_COUNT(ssp)+1 {
+	    if (DEBUG(rv)) {
+		call d_printf (DBG_FD(rv), "\tl=%g r=%g -- s=%g e=%g\n")
+		    call pargi (left) ; call pargi (right)
+		    call pargr (SRANGE(ssp,i)) ; call pargR (ERANGE(ssp,i))
+	    }
+
+	    k = 1
+	    j = left
+	    np = right - left + 1
+	    while (k <= np) {
+	        data[j] = 0.0
+	        j = j + 1
+		k = k + 1
+	    }
+	    if (i == SR_COUNT(ssp)+1) 
+	    	return
+
+	    if (SR_UNITS(ssp) == PIXELS) {
+	        #left = nint ((ERANGE(ssp,i) - RV_GLOB_W1(rv) + 1) + 1)
+	        left = (ERANGE(ssp,i) - RV_GLOB_W1(rv) + 1) + 1
+	    } else {
+	        left = nint ((log10(ERANGE(ssp,i)) - RV_GLOB_W1(rv)) / 
+		    RV_OWPC(rv)) + 1
+	    }
+	    if (apodize == YES)
+	        call fft_cosbel (data[right], left-right+1, -1, RV_APODIZE(rv))
+	    if (i == SR_COUNT(ssp)) {
+		right = npts
+	    } else {
+		if (SR_UNITS(ssp) == PIXELS) {
+	    	    right = SRANGE(ssp,i+1) - RV_GLOB_W1(rv) + 1
+		} else {
+	    	    right = nint ((log10(SRANGE(ssp,i+1)) - RV_GLOB_W1(rv)) / 
+			RV_OWPC(rv)) + 1
+		}
+	    }
+	}
+end