Hello Julians, I’m trying to design a type MyType having a certain number of fields amongst which matrix::AbstractMatrix. In production MyType is intended to have its field matrix modified (hundreds times a day)… I’ve encountered some difficulties in building MyType’s updaters resizing/reshaping ma…

Some workarounds: introduce a wrapper type for matrix:mutable struct ReplaceableMatrix matrix::Matrix{Float64} end struct MyType some_field::SomeType matrix::ReplaceableMatrix end make MyType mutable with all fields immutable, except for matrix:mutable struct MyType const some_f…

A field of a strictly immutable composite type does not need to reference other immutables, and you can make mutation API forward to that field. That’s how many wrappers of mutable arrays work. A mutable composite type would only add the ability to reassign a different matrix to the field, which is …

Do you have a bound on the maximum size of the matrix?

Thank you for your reply. Please, precize what you mean by “…and you can make mutation API forward to that field.” is there a way to make a specific field mutable? By the way, you say that viewing another field is not a good idea?

No sir, I do not have any limit. It can grow to any size… but in practice the number of columns will unlikely go above 40. It’s the number of rows that can go to the thousands… Though my updaters are there to ensure that sizes/data are correct.

Yes, but read on. Whenever you create a matrix, the system allocates you a block of memory for storing this matrix. The reason why you can’t resize!(matrix) is because there is other data near this piece of memory, and easily expanding this matrix might overwrite important data in the surrounding me…

My idea was to have a maximal fixed-size matrix and just store integers telling you which submatrix is currently in use

…Buffers, ok thanks. But what I don’t want is to had more dependencies…

Haha, mutable struct ReplaceableMatrix… was my first idea but thought was too easy… definitely what I’m gonna do!! Thank you!!

Newly relevant: [image] [ANN]: ZeroDimensionalArrays.jl: zero-dimensional arrays/references/boxes Package Announcements ZeroDimensionalArrays.jl is being registered, meaning it has entered the three-day-long wait period. Feel free to suggest breaking changes u…

Dynamic immutable type

New to Julia

nsajko April 12, 2025, 10:19am 12

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Dynamic immutable type

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