Matrix Error

engrAlan · Oct 16, 2012

Can somebody help me resolve this error in Matrix output?

I came across in the internet this useful template but I want to customize to increase its usage.

The Matrix output on the attached MathCad File will have an error when the Number of Pedestal will be greater than 3. I can't figure out which variable limits this situation.

Thank you.

Occupant · Oct 16, 2012

I would say, just looking at it, your Excel spreadsheet only allows for four values. So, how do you exspect to get more out of it?

engrAlan · Oct 16, 2012

No, it's not. because i already tried revising the output range in the excel file to include even 6 pedestals. i doubted the settings of the total number of loads. but i have no idea how this relates to the overall matrix formulation.

Occupant · Oct 16, 2012

Yes, it is. See attached.

engrAlan · Oct 16, 2012

Thanks for your response Occupant. But Final MatrixLoad has no result, this was my problem. one of the error is "This array has an incorrect number of rows and column"

jmcoope3 · Oct 16, 2012

MathCAD also has a limit to how big a matrix can get... might be having a hissy if you're getting too large.

look into making the output an excel file or a CSV.

engrAlan · Oct 16, 2012

Yes, its quite big around 9 x 29 for 1 pedestal, 9 x 116 for 4 pedestals, that is 29 rows (for load comb) will be added for each pedestal added to the matrix.

But i even tried reducing the number of load combination to only 3 (from 29 orig), the matrix size is 9 x 9 for 3 pedestals, 9 x 12 for 4 pedestals and still the error occur in 4 pedestals.

IRstuff · Oct 16, 2012

Your Excel insets don't appear to be correctly inserted in the sheets. They all should have something along the lines of:

XY:={Excel}

You should be using Insert Component | Excel Worksheet, which should give you almost the exact same thing, except for the empty placeholder to the left of a := next to the component.

TTFN
faq731-376

engrAlan · Oct 16, 2012

Excel was embeded as component, please see attached with arguments shown for each excel sheet.

Occupant · Oct 17, 2012

No, I think, you're just being sloppy. Look at attached - green color. I stopped there - otherwise it looks like work and who wants that?

engrAlan · Oct 17, 2012

Sorry Occupant but, i did the review of your attached file and the error is still there. Please take a look on the attached PDF file. I made a comparison between 3 pedestals which gave the MatrixLoad as shown in Page 5 of 10, and with 4 Pedestals which returned first error on page 9 of 10, and eventually Page 10 of 10 is blank.

I am sure its not on the size of Matrix, because i already tried reducing NoOfComb from 29 to 3, but the error is still there.

Occupant · Oct 17, 2012

Let's see if I got this right You want in the end to wind up with a matrix called MatrixCombFactor size:115x7 (assuming 4 pedestals) and each field in that matrix again holding a matrix 29x28 to cover all combinations?

engrAlan · Oct 17, 2012

I found the error guys, it is on the multiplication of the following lines:
CombFactor*submatrix(MatrixLoad,NoOfLoad*k,NoOfLoad(k+1)-1,0,NoOfForce-1)

- The difference between NoOfLoad(k+1)-1] - [NoOfLoad*k] should be equal to the number of loads, (i.e NoOfLoad-1 to account 0, so i change the formula:
CombFactor*submatrix(MatrixLoad,0,NoOfLoad-1,0,NoOfForce-1) and it ran as i expected!

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Matrix Error

engrAlan

Structural

Occupant

Mechanical

engrAlan

Structural

Occupant

Mechanical

engrAlan

Structural

jmcoope3

Mechanical

engrAlan

Structural

IRstuff

Aerospace

engrAlan

Structural

Occupant

Mechanical

engrAlan

Structural

Occupant

Mechanical

engrAlan

Structural

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