I can't change a matrix solution to show the result in a new variable

[fguerra84]

Hello everybody,

I'm trying to change the sum of angles theta 1,2,3 to a new angle phi. The matrix T03 is the solution of A01*A12*A23. I have been using symbolic keywords like substitute, using and other types of solution but nothing works to show the same matrix T03 but with cos(phi) and sin (phi). 

There is some way to do it?

Any help or advice?

Thanks.

[vkofanov · Accepted solution]

Use the symbolic command "substitute" .

In mathcad 15 it looks like this.

[fguerra84]

Thank you Vkofanov, I don't know why this time the command "substitute" worked in Prime, because the times I tried before didn't.

By the way do you know how I can rearrange the element (1,4) the show l1*cos(theta) first, l2... and then l3... I know it's the same, but I want the matrix in that way.

Thank you again.

[Werner_E]

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fguerra84 wrote:By the way do you know how I can rearrange the element (1,4) the show l1*cos(theta) first, l2... and then

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You may try additionally the "collect,theta.1" command in the symbolics. Not sur if it would work the way you want it to be. Its often hard to get Mathcads symbolics to display results exactly the way we have it in mind, ever so often its impossible.

[vkofanov]

[fguerra84]

Finally I did it with "collect", the dot solution doesn't worked for me in Prime.
Thank you Vkofanov & Werner_E.

Regards.

[Werner_E]

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@fguerra84 wrote:

the dot solution doesn't worked for me in Prime.

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What vkofanov pointed out is that the order of the factors and summands differ, depending if you use vector indices or literal indices.

In Mathcad 15 and below literal indices are written using the dot. In Prime its done via the menu or with the keybord shortcut "Ctrl -"