Hi guys! There is a model in which I have to declare a very large matrix (150 columns). The problem is that I do not know how can I break a line when declaring a matrix without actually creating a new row. For example: a = [1 2 3 4 5 6 7 8 9 10] is interpreted a 2x5 matrix. Is there a way to…

You can do this, replace MATLAB’s ... with an open [ and close it the next line like this: a = [1 2 3 4 5 [ 6] 7 8 9 10; 1 2 3 4 5 [ 6] 7 8 9 10]

You can create each row as a vector, transpose it, and vcat the result: julia> vcat([1,2,3, 4,5,6]', [7,8,9, 10,11,12]') 2×6 Array{Int64,2}: 1 2 3 4 5 6 7 8 9 10 11 12 but…really I’d suggest just not doing this. Having a 150-column matrix includ…

I am implementing the NRLMSISE-00 model, which had those constants hard coded into the source code. I just want to use the same thing because it will be easier when a new version is released. However, the ideia to store in CSV and read it in init should be fine also.

This is the syntax: a = [1 2 3; 4 5 6]

Yes, but I cannot break a line without defining a new row. Hence, I have to type 150 floats in one line, which is bad :smiley:

What you mean by breaking lines? The snippet of code above doesn’t have line breaks?

I mean, like in Matlab, in which I can declare a 10x2 matrix by: a = [1 2 3 4 5 ... 6 7 8 9 10; 1 2 3 4 5 ... 6 7 8 9 10] I think in Julia we do not have something to do what ... do.

Oh I see your point. You want to continue the row of 10 elements on the next line of the file by breaking it into chunks of size 5. I am trying to understand the rationale, I don’t have a solution for it.

Yes, precisely. Look at the end of this FORTRAN code: https://ccmc.gsfc.nasa.gov/pub/modelweb/atmospheric/msis/nrlmsise00/nrlmsise00_sub.for If I want to implemente exactly as it was implemented there, then I need to declare a matrix with 150 columns. What I am doing now is to declare each column…

Would it be too bad to ask for a feature like this in Julia? A character to break lines in array without defining a new columns, like: A = [1 2 3 4 5 | 7 8 9 1 2 ]

Wow man! It works! I would have never though about that.

Declare a matrix with break lines

General Usage

Liso June 11, 2018, 6:03am 16

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Declare a matrix with break lines

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