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Users Manual for Program PSD_FOUR





Table of Contents

   Introduction
   Internal calculation procedure
   Input data commands
   Example




Introduction

Program PSD_FOUR calculates the power spectral density of a time-domain variable and writes the result on file UTFIL.

See also:

TRC_IPSD Recreate track irregularities from a PSD-spectra



Internal calculation procedure

Program PSD_FOUR reads data from INFIL, the PSD-spectra is generated by raise the Fourier transformation to the second power.




Input data commands

Input data are read in free format, valid separators between the input values are <space>, <comma>, <tab>, <equal sign> or <carriage return>. The commands can be written both in lower and upper case letters. The operation of the program is controlled by the commands described below; some of the commands also need arguments.

INFIL
File containing the input data curve.
File consisting of value-pair Xvar and Yvar. The file is read in free format. Lines starting with the #-sign are considered as being commentary lines.
Declared= Character*132    Default= Blank

UTFIL
Name of output data file.
Declared= Character*132    Default= Blank

EOF
Command which terminates further input data reading.


Example of an input data file

Following example: Master.psd_fourf can be used as input data file:

##
##      Input data for program PSD_FOUR
##
 INFIL=  ucat/cos_l5d2.sngl
 UTFIL=  ucat/cos_l5d2.fpsd
#