Hello,

I wonder why left matrix give error and right is ok?

Best.

Test1.sm (54 KiB) downloaded 47 time(s).

Wrote

I wonder why left matrix give error and right is ok?

They are identical, but the left one is incompletely dressed.
I don't understand the project. There is nothing more confusing
than subscripts. They are useful if the subscript is a long explicative definition.

Test1(1).sm (59 KiB) downloaded 34 time(s).

I think some definitions are missing






Best regards


Carlos

Wrote

I think some definitions are missing

No, it's the operator formatting of the built-in minor() function. Can be found on the Matrix palette.

Ufss!!! Sorry !!!

You are right.

How I did not see it defined in the floating panel?

Thank you

Carlos

Wrote

I think some definitions are missing

I think it is => this from the palette

Wrote

I think it is =

Some kind of matrix logic ... logic & ½
Not familiar at all, no recollection from Mathcad.
Is it really productive fro the collab originator ?

Jean

Utilities Matrix UNKNOWN Palette.sm (19 KiB) downloaded 32 time(s).

Seems some issue in the symbolic engine about the inversion of minor() when there are units

Wrote

I wonder why left matrix give error and right is ok?

Because the right one comes from an if/else, that force a numerical optimization context while in the left case it's in a symbolic context.

To figure out the difference between K.1 and K.2, look at their content

• add a breakpoint on Mxx and look what it happens inside the loop in the 2 cases
  
• alternatively write on the canvas K.1= and K.2= with "none" optimization

Wrote

Because the right one comes from an if/else, that force a numerical optimization context while in the left case it's in a symbolic contex

About all that: my understanding is only slightly pregnant !
It resumes to solving a tridiagonal system c/w units
conclusively resulting in valued units and coefficients.
Most interesting for more bed time reading.

Thanks to all ... Jean

Maths Tridiagonal [Unknown Units].sm (141 KiB) downloaded 33 time(s).