Certain features of the IP method, to our knowledge not shared by other inversion methods, will be of particular importance in the particular systems to which we shall apply spin-1 inversion. These include the ability to find an explicitly energy dependent potential from phase shifts for a range of energies, the ability to handle a range of energies simultaneously and to include Majorana terms for all potential components. For many applications the important property is that mentioned in the introduction, i.e. that IP inversion lends itself to direct observable to potential inversion. This not only avoids the need for independently determined phase shifts (or $S$-matrix), but actually provides an advantageous method of determining such phase shifts. For a full description of IP inversion as applied in the spin-1/2 case see Refs.[@ketal1; @zuev; @candm]. The formalism presented in Ref.[@candm], whereby energy dependent potentials are obtained from multi-energy datasets, can be used with spin-1 inversion as described here, although energy dependence is not actually exploited in the test cases. A brief general account of IP inversion is given in the next section.

IP inversion for the coupled channel case; application to spin-1 {#ipinv}
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Our notation must reflect the fact that the 