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very dangerous bug in mcad14 m020!

very dangerous bug in mcad14 m020!

very dangerous bug in mcad14 m020!

dear all,
i found a very dangerous bug with such elementary operation like matrix vector multiplication.

if you try to multiply a matrix with a vector that you created using a little program , and the rows of the vector and the columns of the matrix do not match, mathcad nevertheless does the multiplication and gives not warning and completely overflowing results.

see uploaded mcad file:


here, a screenshot:


could you please test if you get the same results / error?
or if this is a specific problem with my computer setup ?


RE: very dangerous bug in mcad14 m020!

Where md(1) is defined?

RE: very dangerous bug in mcad14 m020!

rnd is a bult in function of mathcad.

from the docs:
"rnd(x) Returns a uniformly distributed random number between 0 and x."

could you download the mcad file and please test on your installation ?

RE: very dangerous bug in mcad14 m020!

Works that way for me too on 14m020.  Interestingly, if all the array dimensions are <=10 Mcad does catch the error.  When the dimensions are >10 it does not.

You can post the problem here if you want:


Although if you don't have an active $upport contract you're not eligible for any bug fixes.


RE: very dangerous bug in mcad14 m020!

@IRstuff: thanks for posting the bug to mathcad support.
i have no active $$$upport contract, thats the reason i was posting here and hoping that somehow the bug would "propagate" to mathsoft/ptc.

honestly... how can such a BIG bug slip through ? matrix vector ops are so fundamental..

RE: very dangerous bug in mcad14 m020!

herculon:  I got the same results as you did with MathCad14 M020.  

This is a bug that should be fixed in M030 AND ... M030 should be free to registered users of MathCad 14 free.  

We should not have to pay for bug fixes.  If Microsoft had the same bug fix policy as PTC we would all be using Linux or Apple.  

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