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Prime 7 swapping row and column order from Mathcad 15

FrankM22
8-Gravel

Prime 7 swapping row and column order from Mathcad 15

Hi, I've recently been tasked with updating some Mathcad sheets from version 15 to Prime 7 and have noticed something that has confused me. (Unfortunately as they aren't my sheets and I'm only upgrading them I don't have full permission to upload the mathcad files but I can send some screenshots, but anyways)

 

Using the following equation, on dropping the subscript [ j, jw after the α, they both give the same identical matrix.

SM_9995865_0-1627988735287.png

SM_9995865_1-1627988765583.pngSM_9995865_2-1627988784976.png

 

However, when reintroducing the [ j, jw subscript (sorry I don't know the proper term, again I'm just converting the files - the maths itself is beyond me), the output in Mathcad 15 is different from Prime 7. 

In Prime 7, it creates a vector starting from the first row of α, and then from the second and then third row etc.

 

SM_9995865_3-1627988841134.png

 
However, for 15, it creates a vector starting from the first column of α, and then the second and the third etc.

 

SM_9995865_4-1627988870013.png

Is this something that was changed in the update that I'm not aware of, is there a setting in either of the Mathcad versions which might have been changed that is causing this discrepancy, or is it something else entirely?

 

Thanks in advance.

ACCEPTED SOLUTION

Accepted Solutions
LucMeekes
23-Emerald III
(To:LucMeekes)

Figured it out.

The expression α[j,jw=, with j and jw range variables that span the rows and columns respectively, results in the serialization of the matrix α.

Example:

LucMeekes_0-1627994861610.png

 

Prime does it row by row, Mathcad does it column by column:

LucMeekes_3-1627995189276.png

So yes, there is a difference in behaviour between Mathcad and Prime. (And this is not the only example of that...)

To get the same result in Prime, you could use the transpose operator, but you also need to swap the indices then.:

LucMeekes_2-1627995126648.png

 

Success!

Luc

View solution in original post

2 REPLIES 2
LucMeekes
23-Emerald III
(To:FrankM22)

Is the matrix α the same size in both cases (Mathcad & Prime)?

In Prime it appears to have 20 rows and 32 columns.

You can check sizes with:

rows(α)=

cols(α)=

 

If so, then how do you get indices above 31 in the Mathcad output?

 

Success!
Luc

 

LucMeekes
23-Emerald III
(To:LucMeekes)

Figured it out.

The expression α[j,jw=, with j and jw range variables that span the rows and columns respectively, results in the serialization of the matrix α.

Example:

LucMeekes_0-1627994861610.png

 

Prime does it row by row, Mathcad does it column by column:

LucMeekes_3-1627995189276.png

So yes, there is a difference in behaviour between Mathcad and Prime. (And this is not the only example of that...)

To get the same result in Prime, you could use the transpose operator, but you also need to swap the indices then.:

LucMeekes_2-1627995126648.png

 

Success!

Luc

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