Compute maximax PSDs from the supplied time history imat_fn
g = psd_maximax(t,NSEG,SEGOVPCT,NBLK,BLKOVPCT)
g = psd_maximax(f,5,50,4096,0)
g = psd_maximax(T,NSEG,SEGOVPCT,NBLK,BLKOVPCT,'overlap',OVPCT)
g = psd_maximax(T,NSEG,SEGOVPCT,NBLK,BLKOVPCT,'istart',ISAMP)
g = psd_maximax(T,NSEG,SEGOVPCT,NBLK,BLKOVPCT,'octave',NOCT)
g = psd_maximax(T,NSEG,SEGOVPCT,NBLK,BLKOVPCT,'silent','noprogbar')
PSD_MAXIMAX computes single-sided Maximax Power Spectral Density functions from the supplied time histories in the imat_fn T. All of the supplied time histories must have same length.
NSEG is a required parameter indicating the segment size to use for computing intermediate PSDs that will be enveloped to for the maximax PSD.
SEGOVPCT is a numeric scalar between 0 and less than 100 specifying the percent overlap of time segments. Passing in an empty value specifies the default, which is 0.
NBLK is a required parameter indicating the window size. If it is a scalar it indicates the block size to be used in the PSD calculation. AHamming window will be used. If NBLK is a vector or imat_fn, it should contain the window to be used. The length of the vector indicates the window size.
BLKOVPCT is a numeric scalar between 0 and less than 100 specifying the percent overlap of windows. Passing in an empty value specifies the default, which is 50.
'istart' is an optional input that must be followed by a numeric vector ISAMP that specifies the starting indices into the time histories for the frames to be processed and enveloped. If ISAMP does not contain integer indices, the time histories will be linearly interpolated to estimate the values of the time histories at the specified indices. You cannot specify an overlap if you specify ISAMP.
'octave' is an optional input that performs an Nth octave reduction on each segment PSD before enveloping. It must be followed by a numeric scalar NOCT specifying the Nth octave reduction to be used. Passing in an empty value specifies the default, which is 6.
'silent' is an optional input string that suppresses output during the PSD calculation.
'noprogbar' is an optional input string that disables the progress bar.
OUT is an imat_fn of the same size as T containing the Maximax PSDs.
>> g = psd_maximax(t,8192,0,4096,50)
Maximax PSD Processing Parameters
-------------------------
Number of points: 159681
Time Segment Size: 8192
Block Size: 4096
Segments: 19
Time Overlap: 0 samples (0.00%)
Sampling: uniform
Block Overlap: 2048 samples (50.00%)
Avgs per Segment: 3
Delta F: 1.0000 Hz
Spectral lines: 2049
-------------------------
...Processing time histories
g =
4x1 IMAT Function with the following attributes:
Record Name FunctionType AbscissaSpacing NumberElements
--------------------------- ---------------- ---------------- ----------------
1_(80Z+,80Z+) Power Spectral D Even 2049
2_(99Z+,99Z+) Power Spectral D Even 2049
3_(82Z+,82Z+) Power Spectral D Even 2049
4_(1X+,1X+) Power Spectral D Even 2049
>> g = psd_maximax(t,8192,50,4096,50,'octave',6)
Maximax PSD Processing Parameters
-------------------------
Number of points: 159681
Time Segment Size: 8192
Block Size: 4096
Segments: 37
Time Overlap: 4096 samples (50.00%)
Sampling: uniform
Block Overlap: 2048 samples (50.00%)
Avgs per Segment: 3
Delta F: 1.0000 Hz
Spectral lines: 2049
Noct for Maximax: 6
Fmin: 0.976563 Hz
Fmax: 2000 Hz
Number of Bands: 67
-------------------------
...Processing time histories
g =
4x1 IMAT Function with the following attributes:
Record Name FunctionType AbscissaSpacing NumberElements
--------------------------- ---------------- ---------------- ----------------
1_(80Z+,80Z+) Power Spectral D Uneven 67
2_(99Z+,99Z+) Power Spectral D Uneven 67
3_(82Z+,82Z+) Power Spectral D Uneven 67
4_(1X+,1X+) Power Spectral D Uneven 67
>> g = psd_maximax(t,8192,0,window('flattop',4096),50)
Maximax PSD Processing Parameters
-------------------------
Number of points: 159681
Time Segment Size: 8192
Block Size: 4096 (window vector supplied
Segments: 19
Time Overlap: 0 samples (0.00%)
Sampling: uniform
Block Overlap: 2048 samples (50.00%)
Avgs per Segment: 3
Delta F: 1.0000 Hz
Spectral lines: 2049
-------------------------
...Processing time histories
g =
4x1 IMAT Function with the following attributes:
Record Name FunctionType AbscissaSpacing NumberElements
--------------------------- ---------------- ---------------- ----------------
1_(80Z+,80Z+) Power Spectral D Even 2049
2_(99Z+,99Z+) Power Spectral D Even 2049
3_(82Z+,82Z+) Power Spectral D Even 2049
4_(1X+,1X+) Power Spectral D Even 2049
>>