Calculating Dual Form of SVM Equation

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I am trying to calculate the dual form of an SVM optimisation problem:

Equation for the dual form of the SVM objective: L̃(α) = sum over i from 1 to n of α_i, minus one half times the double sum over i and j of α_i α_j y_i y_j x_i^T x_j, equal to the same expression with x_i^T x_j replaced by k(x_i, x_j).

Dual Form Optimsation Problem

In my algorithm, I have a vector of alphas, vector of target outputs, and a Kernel matrix computing upfront.

However, I am stuck as to what indices alpha and j should be taking here. If i and j are equal, then everything is just squared. Is this for i =/= j?

If so, could I just duplicate each vector and flip it?
 
I'm going to suspect that the ##\sum_{i,j}## in your equation is being used as a shorthand for ##\sum_i\sum_j##, in which case ##\sum_i\sum_j\alpha_i\alpha_j = \alpha_1\alpha_1 + \alpha_1\alpha_2 + \cdots + \alpha_1\alpha_m + \alpha_2\alpha_1 + \cdots + \alpha_2\alpha_m + \cdots + \alpha_n\alpha_1 + \cdots \alpha_n\alpha_m## if ##i = 1 \ldots n## and ##j = 1 \ldots m##.