Delta-rational chord: Difference between revisions
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Suppose that the target delta signature is | Suppose that the target delta signature is | ||
<math>+\! \delta_{ | <math>+\! \delta_{1,1} +\! \delta_{1,2} +\! \cdots +\! \delta_{1,n_1} +\!? +\! \delta_{2,1} +\! \delta_{2,2} +\! \cdots +\! \delta_{2,n_2} +\!? \ \cdots +\!? +\!\delta_{m,1} +\! \delta_{m,2} +\! \cdots +\! \delta_{m,n_m}.</math> | ||
Writing ''a:b:c:...'' as [''a'', ''b'', ''c'', ...] for readability, the chord to be approximated is | Writing ''a:b:c:...'' as [''a'', ''b'', ''c'', ...] for readability, the chord to be approximated is | ||
<math> | <math> | ||
[\alpha_1, \alpha_1 + \delta_{ | [\alpha_1, \alpha_1 + \delta_{1,1}, \alpha_1 + \delta_{1,2}, ..., \alpha_1 + \sum_{l=1}^{n_1} \delta_{1,l}, \\ | ||
\alpha_1 + \alpha_2 + \sum_{l=1}^{n_i} \delta_{ | \alpha_1 + \alpha_2 + \sum_{l=1}^{n_i} \delta_{1,l}, \alpha_1 + \alpha_2 + \sum_{l=1}^{n_1} \delta_{1,l} + \delta_{2,1}, ..., \alpha_1 + \alpha_2 + \sum_{l=1}^{n_1} \delta_{1,l} + \sum_{l=1}^{n_2} \delta_{2,l}, \\ | ||
..., \\ | ..., \\ | ||
\alpha_1 + \cdots + \alpha_m + \sum_{i=1}^{m-1} \sum_{l_i=1}^{n_i} \delta_{ | \alpha_1 + \cdots + \alpha_m + \sum_{i=1}^{m-1} \sum_{l_i=1}^{n_i} \delta_{i,l_i} + \delta_{m,1}, ..., \alpha_1 + \cdots + \alpha_m + \sum_{i=1}^m \sum_{l_i=1}^{n_i} \delta_{i,l_i}]. | ||
</math> | </math> | ||
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and turning the objective function into a sum of univariate objective functions | and turning the objective function into a sum of univariate objective functions | ||
<math> \displaystyle{ \sum_{l_i=1}^n \Bigg( \beta_i r_{l_i} - \beta_i - \sum_{{l_i}=1}^i \delta_{l_i} \Bigg)^2. } </math> | <math> \displaystyle{ \sum_{l_i=1}^n \Bigg( \beta_i r_{l_i} - \beta_i - \sum_{{l_i}=1}^i \delta_{i,l_i} \Bigg)^2. } </math> | ||
The Hessian of the objective function is positive-definite, thus the global optimum can be found by setting all individual partial derivatives to zero. | The Hessian of the resulting objective function is positive-definite, thus the global optimum can be found by setting all individual partial derivatives to zero. | ||
== DR and RTT == | == DR and RTT == | ||