Usage: 3dMean [options] dset dset ...
Takes the voxel-by-voxel mean of all input datasets;
the main reason is to be faster than 3dcalc.
Options [see 3dcalc -help for more details on these]:
-verbose = Print out some information along the way.
-prefix ppp = Sets the prefix of the output dataset.
-datum ddd = Sets the datum of the output dataset.
-fscale = Force scaling of the output to the maximum integer range.
-gscale = Same as '-fscale', but also forces each output sub-brick to
to get the same scaling factor.
-nscale = Don't do any scaling on output to byte or short datasets.
** Only use this option if you are sure you
want the output dataset to be integer-valued!
-non_zero = Use only non-zero values for calculation of mean or squares
-sd *OR* = Calculate the standard deviation, sqrt(variance), instead
-stdev of the mean (cannot be used with -sqr, -sum or -non_zero).
-sqr = Average the squares, instead of the values.
-sum = Just take the sum (don't divide by number of datasets).
-count = compute only the count of non-zero voxels.
-mask_inter = Create a simple intersection mask.
-mask_union = Create a simple union mask.
The masks will be set by any non-zero voxels in
the input datasets.
-weightset WSET = Sum of N dsets will be weighted by N volume WSET.
e.g. -weightset opt_comb_weights+tlrc
This weight dataset must be of type float.
N.B.: All input datasets must have the same number of voxels along
each axis (x,y,z,t).
* At least 2 input datasets are required.
* Dataset sub-brick selectors [] are allowed.
* The output dataset origin, time steps, etc., are taken from the
first input dataset.
*** If you are trying to compute the mean (or some other statistic)
across time for a 3D+time dataset (not across datasets), use
3dTstat instead.
++ Compile date = Sep 1 2021 {AFNI_21.2.06:linux_ubuntu_16_64}