dgpwl(1)

PROGRAM
dgpwl - Creates a set of piecewise linear periodic signals.

SYNTAX

dgpwl

-o  resulting image

[-i]
    input value file (xviff file)

[-trigger]
    trigger input

[-v]
    number of vectors

[-n]
    number of points

[-s]
    sampling frequency

[-l]
    signal minimum

[-m]
    signal maximum

[-p]
    signal period

[-r]
    rise time

[-f]
    fall time

[-w]
    pulse width

[-b]
    initial delay

[-d]
    data processing direction (0 = down vectors, 1 = across bands)

[-t]
    lets user choose data type of image:
     'float' (select data type),
      or 'complex' (choose data type)
       [default = float]

[-V]
    Gives the version for dgpwl

[-U]
    Gives the usage for dgpwl

[-P]
    Prompts for command line options

[-A [file1]]
    Creates the answer file called dgpwl.ans or file1

[-a [file1]]
    Uses dgpwl.ans or file1 as the answer file

DESCRIPTION
creates a one dimensional set of signals. The image pixel values follow a square waveform. The user can specify the period, phase, minima and maxima, sampling frequency, rise and fall times, an initial delay, and signal dimensions.
If a "value file" is specified, it will contain a kernel that describes the signal ensemble to be generated. This is an viff format file. The information will be contained in a single vector of float type information. The row and column size information is irrelevant. The format of the information is as follows:
[<sampling freq.><minimum><maximum><period><rise><fall><width><init. delay>]
where each item enclosed in triangular brackets represents a single float. The information set in square brackets is repeated as a group one per vector.
For example if 2 vectors are specified, and the first vector has a sampling frequency of 10.0, an minimum of 6.0, a maximum of 10.0, period of 2.0, rise of 0.0, fall of 1.0, width of 13.0, phase of 0.0, initial delay of 0; the second vector is identical, except that the minimum is 3.0 and the initial delay is 7, then the image data in the "parameter file" will look like this:
band #1: 10.0 10.0
band #2: 6.0 3.0
band #3: 10.0 10.0
band #4: 2.0 2.0
band #5: 0.0 0.0
band #6: 1.0 1.0
band #7: 13.0 13.0
band #8: 0.0 7.0
The advantage of this "parameter file" is that it allows the creation of an ensemble of 1D signals that independant of each other. Number of data sets, number of points per data set, data type, and process direction must be entered on the command line, or the defaults can be taken. If more data sets are requested than are specified in the parameter file, then an error will occur. If fewer data sets are requested than are specified, then the unused parameters will be ignored.
A non zero initial delay causes the number of points indicated to be zeroed. After the indicated delay, the sinusoidal signal is generated with a time shift equivalent to the delay specified (i.e. the t=0 line is shifted to the right based on the value of the delay).
NOTE: According to the Sampling Theorem, the sampling frequency should be at least twice that of the signal frequency to generate a signal properly.
The resulting images may be of type FLOAT or COMPLEX.
Data can be processed with either band or vector orientation. The default data processing direction is in the vector direction. This means that data stored in multiband format will be processed as a set of data sequences, where each sequence corresponds to a pixel location, and the points of each sequence are defined by the bands corresponding to that pixel location. The direction of processing can be changed so that each band is processed as a signal (instead of each vector being a signal) by setting the -d option to 1.

The trigger input can be used to cause dgpwl to re-execute when used inside cantata. No image is read from this input.

REQUIRED ARGUMENTS

-o  type: outfile
    desc: resulting image

OPTIONAL ARGUMENTS

-i  type: infile
    desc: input value file (xviff file)

-trigger
    type: infile
    desc: trigger input

-v  type: integer
    desc: number of vectors
    default: 1
    bounds: value > 0

-n  type: integer
    desc: number of points
    default: 256
    bounds: value > 0

-s  type: float
    desc: sampling frequency
    default: 2
    bounds: value > 0.0

-l  type: float
    desc: signal minimum
    default: 0
    bounds: no range checking

-m  type: float
    desc: signal maximum
    default: 1
    bounds: no range checking

-p  type: float
    desc: signal period
    default: 1
    bounds: value > 0.0

-r  type: float
    desc: rise time
    default: 0
    bounds: value >= 0.0

-f  type: float
    desc: fall time
    default: 0
    bounds: value >= 0.0

-w  type: float
    desc: pulse width
    default: 0
    bounds: value >= 0.0

-b  type: integer
    desc: initial delay
    default: 0
    bounds: value >= 0

-d  type: boolean
    desc: data processing direction (0 = down vectors, 1 = across bands)
    default: true

-t  type: string
    desc: lets user choose data type of image
    allowed values:
     'float' (select data type),
      or 'complex' (choose data type)

EXAMPLES
dgpwl -i params.xv -o plinear.xv -t float -d 0
dgpwl -o test.xv -t complex -d 1

SEE ALSO
intro(1), verror(3), vgparms(3), vutils(3), ldgpwl(3)

RESTRICTIONS
can only generate VFF_TYP_FLOAT and VFF_TYP_COMPLEX type images.

COPYRIGHT
Copyright 1992, University of New Mexico. All rights reserved.