indexFromModeNumber

return the linear index into a spectral matrix given (k,l,j)

Developer documentation: this item describes internal implementation details.

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Declaration

 index = indexFromModeNumber(kMode,lMode,jMode)

Parameters

• kMode integer
• lMode integer
• jMode integer vertical mode number present in self.j

Returns

• index a non-negative integer number

Discussion

This function will return the linear index in a spectral matrix given a mode number. Scalar and column-vector inputs preserve their shape and ordering; conjugate mode numbers map to their primary coefficient.