start index from 0 instead of 1

[Bin Wang]

Is there any possible to add a "button" to switch the index from 0 instead of 1?
Or Can you provide a version of it? The natural selection of C/C++ index is from 0, this will be very convenient to use it directly.

Now I had to use it like MatA.get(i+1,j+1) etc

[Petr Kessler]

The implementation follows the CRS format described at http://netlib.org/linalg/html_templates/node91.html where the indexing starts from 1.

But I have to say I also struggled a bit with this since in programming base 0 is much more common.

The struggle will be even more real after the operator[][] is added.

I guess this decision has been made according to the mathematical notation where a_11 means element on 1st row in 1st column.

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Some documents however define CRS with base 0. I think it would be much more intuitive and easier to use and would simplify internal algorithms as well (since now I have to subtract 1 when accessing elements and it's a bit confusing).

I'll think about this and probably would change the base in the future (although it'll be a big BC break).

[Petr Kessler]

I'll try to create separate branch base0 later today.

[Bin Wang]

Thanks very much for your consideration and time. I'm really looking forward to see this branch.

[Petr Kessler]

I've just added branch base0. All tests seem to be passing.

Could you please test it that it works for you, @BinWang0213 ?

[Bin Wang]

Thx for your help. It works so good!