creates iData object
[omega, swConv] = SW_IDATA(spectrum, 'option1', value1 ...)
It creates iData object (<a href=http://ifit.mccode.org>http://ifit.mccode.org</a>)
and convolutes the spectra with a fixed instrumental resolution, assuming
the energy and Q axis are linear.
Input:
spectrum Calculated spin wave spectrum, struct type.
Options:
fwhmE Full width half maximum of the Gaussian energy
resolution. Works properly only for linear energy axis.
fwhmQ Full width half maximum of the Gaussian momentum
transfer resolution in A^-1 units. Works properly only
for linear scans in reciprocal space. Be carefull for
example for scans like [1, QK, 0] where the equal QK
steps give unequal steps in the A^-1 reciprocal space.
nInterp Number of axis subdivision before convolution, equal
for Q and E.