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Extract a selection of fields from a fieldset. The vector supplied as the argument provides the set of indices to be used. For example:# copies fields 2, 1, 3 of x into y
x = |2, 1, 3|
y = x[i]
fieldset abs ( fieldset )
Returns the fieldset of the absolute value of the input fieldset at each grid point or spectral coefficient. Missing values are retained, unaltered by the calculation.
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