vyp Year Power (Amplitude) Spectrum

The power spectra is produced with a non-power-of-2 FFT from the time series.

Dimensionally, frequency is along the x-axis, the y-axis contains the order of the spherical harmonic, M, from -L to +L, and the z-axis contains the power [*,*,1]. The FITS header keyword, CD1_1, gives the conversion factor (microHz/pixels) for the x-axis.

Data products up to mrvyp951226 include the power and phase and have an L range of (0<=L<=30). Products after that date do not include the phase and have an L range of (0<=L<=45).

Steps involved:
1. Calculate the power spectra of a GONG time series image with pseries.
 lpar pseries
        input = "@ts"           List of input Time-Series images
       output = "@ps"           List of output Power-spectrum images
 (type_output = "gong")         Output data type (fft|power|gong)
         (pad = "none")          Zero padding (none|1st|2nd)
      (debias = yes)            Debias time series prior to FFT
 (use_gapfill = yes)            Used gap-filled data?
    (do_phase = no)             Output phase spectra
      (window = "none")         Window (bartlett|hamming|hanning|parzen|welch|n
     (verbose = yes)            Verbose output
        (mode = "a")

 output
 mrvypYYMMDDd[000-045]

 sample FITS header output
 GHIST018= 'Task PSERIES2 (96/06/25 17:58:45, V93.2.31)'
 GHIST019= 'input=/int01/chavez/Year/Year/mrvyt951208ed045.imh,type_output=g'
 GHIST020= 'ong,window=none,use_gapfill=yes'

2. Write the power spectra to a DSDS tape.
 tape1 (0<=L<=45) 2.34Gbytes (for one entire GONG year)

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