How to get the alpha_i * y_i in Libsvm 3.22 ?

[UnbearableFate]

as my title says,I want to get the alpha_i * y_i in Libsvm 3.22 but don't know how to do it. the sv_coef now is a double[][] array and I can't get a_i * y_i just use the model.sv_coef[i] like most past answers I asked the same question in http://stackoverflow.com/q/43348979/3097907 there are some more information there. I hope anyone can help me with this question ,Thank you.

PS: my original problem is solving this Formula gradient(J) = -0.5 X sum(a*_i X a*_j X y_i X y_j X Km(x_i,x_j) ) (from SimpleMKL formula.11 )