Initialization Matrix Array on BBC SDL

[zachnoland]

I know that in BBC BASIC arrays can be treated like single or double arrays or even triple arrays, this triple array is something unique from most programming languages. Okay, let's get straight to the topic of discussion.

If you use a single array, you can initialize it like this and declare it directly like this:

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10 DIM A%(2)
20 A%() = 1, 2, 3

But what about Matrix or double array?
As far as I know it has to be initialized manually

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10 DIM A(2, 2)
20 A(0, 0) = 1 : A(0, 1) = 2 : A(0, 2) = 3
30 REM ETC....

This is quite tiring, There is actually another way using for loops, but it is not so flexible(if the value in the array matches what i want).

when compared to modern programming languages.
C++ Example:

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int number[2][2] = {{1,2, 3}, {1, 2, 3}, {1, 2, 3}};

I know this is a bit illogical compared to modern programming languages.

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20 A%() = 1, 2, 3

But is there a way to create a double array the same way as a single array?

[Richard Russell]

But is there a way to create a double array the same way as a single array?

There are two straightforward ways of initialising a 2-dimensional array, that I am aware of.

The first way:

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      DIM A(2,2)
      A() = 1,2,3,4,5,6,7,8,9

The second way:

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      DIM A(2,2)
      A(0, 0 TO 2) = 1,2,3
      A(1, 0 TO 2) = 4,5,6
      A(2, 0 TO 2) = 7,8,9

The first is easier, but doesn't make it obvious which initial value goes into which element (you have to know that BBC BASIC's arrays are row-major). The second is more long-winded, and relies on the array-slicing extension, but makes it obvious which value goes where.

Because you can omit the final index, the second example can also be written:

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      DIM A(2,2)
      A(0, 0 TO) = 1,2,3
      A(1, 0 TO) = 4,5,6
      A(2, 0 TO) = 7,8,9

[zachnoland]

The second way:

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      DIM A(2,2)
      A(0, 0 TO 2) = 1,2,3
      A(1, 0 TO 2) = 4,5,6
      A(2, 0 TO 2) = 7,8,9

the second example can also be written:

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      DIM A(2,2)
      A(0, 0 TO) = 1,2,3
      A(1, 0 TO) = 4,5,6
      A(2, 0 TO) = 7,8,9

I think both of these methods are quite helpful, the code is also quite easy to understand .