OptimizationVariables.x0

OptimizationVariables.x0(total_budget)

Default initial guess: each variable’s default_x0 concatenated.

The budget is shared out across the cells of every spending variable, so the guess sums to total_budget however many of them there are and every spending cell starts at the same amount. With one spender this is exactly default_x0(total_budget); with two, splitting matters – giving each the whole budget would start the solver at twice it, outside the equality constraint before the first step.

A variable that does not spend is handed the total untouched: it is in its own units, and its default ignores the figure anyway.