41CL Quiz: Determinant of 30x30 anti-Identity matrix

[Valentin Albillo]

(05-11-2018 09:10 AM)Ángel Martin Wrote:  This quiz is just for you, proud owners of a 41CL: -

Sorry, Ángel, you know I couldn't resist ...

Quote:Calculate the determinant of a 30x30 matrix with all elements equal to "1" except the diagonal, which has all zeros. I call this type "anti-Identity", but it's totally made up for you purists out there so don't nail me down just yet.

The exact result is Det = -29

My solution returns -28.999999977 in 11 minutes, give or take...

I know, I know, this is just for the 41CL but nevertheless here's the result for the HP-71B under J-F Garnier's Emu71. From the command line:

>DESTROY ALL @ OPTION BASE 1 @ DIM A(30,30),C(30,30)
>MAT A=CON @ MAT C=IDN @ MAT A=A-C @ DET(A)

      -29.0000000001

The timing is 0.15 seconds, give or take a hundredth ...

Have a nice weekend and best regards.
V.