Minimal Reproducible Example using JuMP set = Symbol[] m = Model() @variable(m, x[i in set]) @objective(m, Min, sum(x; init=0)) In this case, optimization is not impossible; rather, an unexpected error occurs when the program executes at @objective. ERROR: LoadError: MethodError: no method matchi…

you can use the generator syntax: using JuMP set = Symbol[] m = Model() @variable(m, x[i in set]) @objective(m, Min, sum(x[i] for i in set; init=0.0))

JuMP reports an error when attempting to sum the empty DenseAxisArray as the objective function

Specific Domains Optimization (Mathematical)

odow October 21, 2025, 8:52pm 3

Hi @karei, thanks for this bug report. I’m fixing this now

1 Like

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JuMP reports an error when attempting to sum the empty DenseAxisArray as the objective function

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