List of functions in Spec_io.dll for Mathcad
Copyright 1999, M. V. Moody,  All Rights Reserved 
for questions or comments contact M. Vol Moody (mvmoody@umd.edu)

window function:

Window(window choice, number of points)

Generates a windowing vector. Available windowing functions are hanning, hamming, triangle, blackman, blackman harris, and flattop

power spectrum:

PowerSpectrum(time record, averages, points per average, window)

Converts a data record from the time domain into the frequency domain (i.e. it gives the magnitude squared of the data record as a function of frequency). The units of PowerSpectrum are [unitsrms(input vector)]2

power spectral density:

PSD(time data, sample rate,averages, points per average, window)

Converts a data record from the time domain into the frequency domain and gives the magnitude squared per unit bandwidth. The units of PSD are [unitsrms(input vector)]2/Hz.

coherence: 

Coherence(time record 1, time record 2, averages, points per average, window)

Gives the output power due to the input divided by the total input power.

transfer function: 

TransferFunction(input time record, output time record, averages, points per average, window)

Calculates a system's response to a stimulation.

cross power spectrum:

CrossSpectrum(input time record, output time record, averages, points per average, window)

Gives the product of two power spectra.

overlap:

Overlap(time record length, number of intervals, length of intervals)

Gives the degree of overlap between adjacent records for a given set of parameters.

butterworth filter:

Butterworth(time record, order/2, corner frequency, low pass|high pass)

Passes a time record through a butterworth filter.

time domain filtering:

MakeFilter(time record, filter type, parameter, pass type, order, 1st corner frequency, 2nd corner frequency)

Returns a filtered time signal. This function is adapted from the mkfilter function of A. J. Fisher of The University of York (www.cs.york.ac.uk/~fisher).

data file decimation:

Decimate(str2vec("filename"), decimation, number of channels)

Reduces the sample rate of a file containing time records in 2-byte integer format.

vector interpolation:

Resample(f(x), x starting value, current x interval, new x interval)

Resample a time record to a higher rate.

binary write:

WriteBin("filename", overwrite|append, matrix, datatype)

Writes a file to disk in binary format.

binary read:

ReadBin(filename", row offset, rows, columns, datatype)

Reads a file in binary format. This function can also be used to read a text file.

read wave header:

ReadWaveHdr("filename")

Reads the header information from a .wav file

read wave data:

ReadWaveDat(filename",hdr)

Reads the data portion of a .wav file

wave write:

WriteWav(filename", data, rate, datatype)

Writes a .wav file

formated write:

WriteFor("filename", overwrite|append, matrix, str2vec("format"), number of columns)

Writes data to a text file using a single format designation.

matrix formated write:

WriteForM("filename", overwrite|append, matrix, str2vec("format string"))

Writes a matrix to a text file using a separate format designation for each column.

string write:

WriteStr("filename", overwrite|append, str2vec("string"))

Writes an ASCII string to a text file.

file length:

FileLen("filename")

Gives the length of a file in bytes.