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I have a matrix that I'm doing calc 1

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dik

Structural
Apr 13, 2001
26,051
The program is SMath Studio.

I have a matrix that I'm doing calculations in, and it uses units. Is there any way of converting the units within the matrix. I'm looking to convert them to kN and kPa, etc. The default values are a bit 'clunky'. I've attached an example.
 
 https://files.engineering.com/getfile.aspx?folder=611efd68-b61f-4084-a250-390c43e280ba&file=WindLoad.pdf
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Why not just use unitless values in the matrix, then multiply the matrix by the necessary unit?

Something like:

X := [ 1,1,1;2,2,2;3;3;3 ] * kPa


Aside: What is the "1" text doing in your matrix in the left-hand column? Is that a non-numerical annotation?

STF
 
The wind loading forces on the various surfaces are defined as: 1, 1E, 2, 2E, 3, 3E, etc. I'm using the string (text) value to identify the forces and surfaces. SMath allows the various column values in a matrix to be different units... some are meters, some kiloNewtons, some kiloPascals... I can try treating the items as a vector, but, am using elements of the matrix for calculating other elements in the matrix, sometimes based on 'if' constructs and 'for' constructs.

Dik
 
Added a part of the calculations... in fact, the matrix starts as a single 8x1 matrix and the other one starts as a 12x1 matrix and ends up as a 8x15 or 8x16 matrix or a 12x... All the added columns are added by calculations similar to attached.

Dik
 
 https://files.engineering.com/getfile.aspx?folder=301ad992-21f1-429e-ad3a-2e7e5a07edd0&file=Part_Matrix.pdf
Out of my depth now... I'm still just using Smath for simple stuff. The notations are all different. IIRC, Mathcad R13 refused to tolerate mixed units in matrices.

To slightly improve the clunkiness of units, can you re-define them, or better yet define new ones?

You may find some tips here:
STF
 
Why simple stuff... it's much better... my problem is thsy I'm curious, and have found a new toy. I'll try re-defining things; I understand that units can be redefined. and maybe make kPa and N the default.

Forgot to say thanks... I generally put revisions in itallics.

Dik
 
SparWeb: The attached shows another example of using 'mixed' variables in a matrix/array. It's incredible for accessing data. The arrays are dynamic, so you can add additional columns to them; I haven't tried rows. You can insert values, or calculate values... really handy.

Dik
 
 https://files.engineering.com/getfile.aspx?folder=e8568a07-5c93-4cc6-bfb3-ed038a835525&file=Example.sm
That is interesting!

BTW, around my house is #2 for 6 inches, and then #6 down as far as I've ever cared to dig!

STF
 
and can be very powerful...

Dik
 
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