vpa(Fv,5) can not consider all the terms
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Fv = - 4.4574e-25*x^21 + 3.0044e-21*x^20 - 5.6303e-17*x^19 + 1.7379e-13*x^18 - 1.4891e-9*x^17 + 1.3636e-8*x^16 - 2.8806e-9*x^15 - 2.0262e-7*x^14 - 7.3855e-8*x^13 - 4.8971e-7*x^12 + 0.000011088*x^11 + 0.000021129*x^10 - 0.000080694*x^9 + 0.00010399*x^8 - 0.0011636*x^7 - 0.010797*x^6 - 0.00084088*x^5 - 0.2542*x^4 + 0.1897*x^3 - 2.0757*x^2 + 0.78487*x + 0.078487;
%% And Can it be arranged in ascending order (Please help!)
%% vpa(Fv,5) can not consider all the terms
Have a try!
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Walter Roberson
2021-6-5
It is not clear what you mean about considering all of the terms. vpa(Fv,5) looked fine to me. I did notice, though, that vpa() rounds to that number of significant digits, and perhaps what you want is to round in absolute digits.
sympref('PolynomialDisplayStyle', 'ascend')
syms x
Fv = - 4.4574e-25*x^21 + 3.0044e-21*x^20 - 5.6303e-17*x^19 + 1.7379e-13*x^18 - 1.4891e-9*x^17 + 1.3636e-8*x^16 - 2.8806e-9*x^15 - 2.0262e-7*x^14 - 7.3855e-8*x^13 - 4.8971e-7*x^12 + 0.000011088*x^11 + 0.000021129*x^10 - 0.000080694*x^9 + 0.00010399*x^8 - 0.0011636*x^7 - 0.010797*x^6 - 0.00084088*x^5 - 0.2542*x^4 + 0.1897*x^3 - 2.0757*x^2 + 0.78487*x + 0.078487
mapSymType(Fv, 'rational', @(e)round(e,5))
Is that what you were talking about?
Notice that a lot of the high-order terms are now missing, because their coefficient rounded to 5 decimal places was 0.
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Walter Roberson
2021-6-6
None of the built-in MATLAB display formats will do that for you.
If you were preparing a character vector with the results, then you would have more options.
Do you need the result to be character? Do you need the result to be symbolic? Do you need to write this out to a file? Is this to be displayed in a GUI?
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