Delta-rational chord: Difference between revisions

Cmloegcmluin (talk | contribs)
ArrowHead294 (talk | contribs)
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We can replace the 1 with x, vary x and ask, "By at least how much do the deltas have to be off for any x?"
We can replace the 1 with x, vary x and ask, "By at least how much do the deltas have to be off for any x?"


Rewriting a bit, if 1:''r''<sub>1</sub>:''r''<sub>2</sub>:...:''r''<sub>''n''</sub> has delta signature +ε<sub>1</sub> +ε<sub>2</sub> ... +ε<sub>''n''</sub> (where the chord is written to start on 1, i.e. 1:1+ε<sub>1</sub>:...), let <math>D_i = \sum_{k=1}^i \delta_i</math> (the ''target'' delta signature) and <math>E_i = \sum_{k=1}^i \epsilon_i</math> (the ''approximating'' delta signature). Then the resulting linear least-squares optimization problem is
Rewriting a bit, if 1:''r''<sub>1</sub>:''r''<sub>2</sub>:...:''r''<sub>''n''</sub> has delta signature {{nowrap|+ε<sub>1</sub> +ε<sub>2</sub> ... +ε<sub>''n''</sub>}} (where the chord is written to start on 1, i.e. 1:1+ε<sub>1</sub>:...), let <math>D_i = \sum_{k=1}^i \delta_i</math> (the ''target'' delta signature) and <math>E_i = \sum_{k=1}^i \epsilon_i</math> (the ''approximating'' delta signature). Then the resulting linear least-squares optimization problem is


<math>
<math>
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=== Partially DR ===
=== Partially DR ===
For approximating a target delta signature of the form <math>+\delta_1 +? +\delta_3</math> with the chord <math>1:(1+E_1):(1+E_2):(1+E_3)</math> (where the +? is free to vary), the least-squares problem is
For approximating a target delta signature of the form <math>+\delta_1 +? +\delta_3</math> with the chord <math>1:({{nowrap|1 + E_1}}):({{nowrap|1 + E_2}}):({{nowrap|1 + E_3}})</math> (where the +? is free to vary), the least-squares problem is


<math>
<math>