Lookup with linear interpolation

The preceding formulas were applied in the example shown in Figure 9-4, to perform table lookup with linear interpolation in the simple data table in A5 B8. The intermediate values shown in B13 B17 in Figure 9-5 were used to develop, in a stepwise manner, the following interpolation formula used in B18. 

LOOKUP (worksheet function) 82 Lookup Reference functions 81 lookup in table, with linear interpolation 171 Loop, Do While... (VBA) 268 loop, exiting from (VBA) 269 Loop, For Each...Next (VBA) 268 Loop, For...Next (VBA) 268 looping (VBA) 267 LOWER (worksheet function) 79... 

Moore [Moore, 1977b] studied the effect of oscillator implementation using lookup tables and found that linear interpolation produces the least distortion and that truncation produces the worst. This result was confirmed by Hartmann [Hartmann, 1987], Another possibility is to use a recursive (HR) filter with poles located on the unit circle. This coupled form [Tierney et al., 1971] offers a alternate method that avoids using memoiy space. Frequency resolution requirements were calculated by Snell in a superpipeline oscillator design for dynamic Fourier synthesis [Snell, 1977]. 

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