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solving simultaneous equations with Solve
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Joined: 10/01/2017(UTC) Posts: 31 Location: Alberta
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hi, I used the Solve function a lot before but for some reason it does not work for this simple example. I need to get the RayLeigh Damping factors alpha and beta using two frequencies, so two simple simultaneous equations should do it. tried using Solve but no luck. Does anyone know why it is not solving? Thanks in advance test.sm (6kb) downloaded 8 time(s).
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1 user thanked PompelmoTell for this useful post.
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You can use roots() for your function. And a vectorize() can simplify it. However, to use Assign() you will need this function to merge vars and solutions. Regards Assign_without_Maxima Solve().sm (8kb) downloaded 15 time(s).
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1 user thanked overlord for this useful post.
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Joined: 10/01/2017(UTC) Posts: 31 Location: Alberta
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Thanks Overlord, PompelmoTell, greatly appreciated!!
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Joined: 11/01/2018(UTC) Posts: 133 Location: Wisconsin Was thanked: 61 time(s) in 38 post(s)
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Greetings, Another approach would be to use some elbow grease, you can substitute terms by hand and solve for 𝛼 and 𝛽: Keypress (You can copy/paste the following into your worksheet): Code:α:{2*D*ω.1*ω.2}/{ω.1+ω.2}
β:α/{ω.1*ω.2}
*NOTE: ω.1 and ω.2 shown above are variables with subscript, they are not vectors ω[1 and ω[2; You should be able to substitute ω.1 for ω[1 if that serves your purposes. - - - - Kenny Lemens, P.E. |
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Joined: 15/07/2010(UTC) Posts: 437 Location: Beer-Sheva Was thanked: 520 time(s) in 288 post(s)
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If the damping coefficients are denoted by α1 and α2, you can use the function al_nlegsoive test.sm (7kb) downloaded 9 time(s).
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2 users thanked Ber7 for this useful post.
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on 06/04/2022(UTC), on 06/04/2022(UTC)
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Joined: 23/07/2013(UTC) Posts: 1,128 Was thanked: 509 time(s) in 339 post(s)
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solving with uni's latest addition mathcad blocks; you wouldn't need Eq: actually, but it can be shown. mathblock.sm (6kb) downloaded 15 time(s).Edited by user 07 April 2022 23:29:29(UTC)
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I think this is the most sophisticated method of my way. It can get unknowns from equation, solve them. In the end assigns numerical values to unknowns. You don't need to define alpha or beta or any variable. All process is automatic. Regards mathblock_v2.sm (6kb) downloaded 15 time(s).There is also this way for guess define. Edited by user 08 April 2022 01:58:41(UTC)
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Joined: 15/07/2010(UTC) Posts: 437 Location: Beer-Sheva Was thanked: 520 time(s) in 288 post(s)
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Originally Posted by: overlord I think this is the most sophisticated method of my way. It can get unknowns from equation, solve them. In the end assigns numerical values to unknowns. You don't need to define alpha or beta or any variable. All process is automatic. Regards There is also this way for guess define. This is good, but for a system of linear equations(our case), the guess can be arbitrary. Edited by user 08 April 2022 08:30:49(UTC)
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And finally a version with Solve() and list injection region: mathblock_Solve.sm (5kb) downloaded 15 time(s). |
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Greetings, If plugins are considered, you can also consider the use of Maple: - - - In the image I posted, the 'equal sign' shown on those two equations are actually symbolic equals; keypress: [ctrl] + [.] instead of keypress [=]. Kenny Lemens, P.E. |
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Hi. The isol solution, using only the Mathcad block plugin. isol_example.sm (69kb) downloaded 22 time(s). isol_example.pdf (35kb) downloaded 9 time(s).Best regards. Alvaro.
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Joined: 10/01/2017(UTC) Posts: 31 Location: Alberta
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Thank you all for the feedback, is there a literature or manual to explain the Mathcad block plugin? Thanks
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Originally Posted by: Mido0 Thank you all for the feedback, is there a literature or manual to explain the Mathcad block plugin ? For that particular example, maple is an algebraic export. Mathcad block has not yet been exemplified in Smath Community of what it can do vs what native Smath can't. Cheers ... Jean. Codes Solve.sm (13kb) downloaded 9 time(s).
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Exercise the Mathcad bloc
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Joined: 23/07/2013(UTC) Posts: 1,128 Was thanked: 509 time(s) in 339 post(s)
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Originally Posted by: Mido0 Thank you all for the feedback, is there a literature or manual to explain the Mathcad block plugin? Thanks We have what Viacheslav provided us. There are some samples or functions too which individual users uploaded. You can look the extension page for some examples. And there are some samples in forum topic that users posted. It may be a small bunch, but we try to understand its capabilities. This feature/plugin is also new to us. Regards https://en.smath.com/forum/yaf_postst726_Mathcad-Toolbox.aspx
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