Hi, I’d like to mutate a scalar variable. For example, if x is a vector, then x .= x_new works fine for mutation. However, when x is a Number, e.g., x = 1.0, x .= x_new does not work properly. Also, I cannot find a way to mutate a scalar variable x.

You cannot mutate scalar values. But a 1x1 array is not a scalar, and you can mutate it just fine. Also, you can do x*x: jl> x = rand(1,1) 1×1 Matrix{Float64}: 0.040743095726171186 jl> x * x 1×1 Matrix{Float64}: 0.0016599998493519487 It doesn’t work for vectors, though, since multiplication is…

Mutation of a scalar variable

New to Julia

Mason June 30, 2021, 5:26am 2

1.0 is a Float64 which is immutable, it cannot be mutated. You should instead just rebind it

x = x_new

Why did you want to mutate a number?

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Mutation of a scalar variable

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