how solve nonlinear equations ?

6 visualizzazioni (ultimi 30 giorni)
ahmed ashiry
ahmed ashiry il 18 Feb 2015
Risposto: Erik S. il 18 Feb 2015
how to solve nonlinear equations ?
these 9 equations in 3 unknown but nonlinear
31.65951=sqrt((20460991.052399-x)^2+(11012393.207537-y)^2+(13140061.841029-z)^2)-sqrt((20462649.31-x)^2+(11012196.356-y)^2+(13137623.266-z)^2) 243.75898=sqrt((1704791.07688-x)^2+(20550181.098118-y)^2+(16863812.406607-z)^2)-sqrt((1706135.95-x)^2+(20548561.881-y)^2+(16865760.323-z)^2) -349.85327=sqrt((18327975.818007-x)^2+(1722639.77547-y)^2+(18786981.252914-z)^2)-sqrt((18326680.829-x)^2+(1720514.194-y)^2+(18788376.839-z)^2) -575.16382=sqrt((12050174.649623-x)^2+(-9980816.456693-y)^2+(21382458.132242-z)^2)-sqrt((12049062.298-x)^2+(-9983309.044-y)^2+(21381885.534-z)^2) 441.83588=sqrt((6415962.553149-x)^2+(15826350.755284-y)^2+(20754833.300093-z)^2)-sqrt((6418526.123-x)^2+(15826408.315-y)^2+(20754019.037-z)^2) -255.03605=sqrt((18966834.575125-x)^2+(6395897.26812-y)^2+(17720969.794907-z)^2)-sqrt((18965851.475-x)^2+(6393896.947-y)^2+(17722730.048-z)^2) 258.29132=sqrt((26283508.487939-x)^2+(-1051136.220342-y)^2+(4730820.234619-z)^2)-sqrt((26282933.567-x)^2+(-1051377.055-y)^2+(4733941.445-z)^2) -550.04848=sqrt((15456741.418182-x)^2+(19573966.047127-y)^2+(-9158923.170409-z)^2)-sqrt((15456435.97-x)^2+(19572808.522-y)^2+(-9161842.101-z)^2) 549.43288=sqrt((25702282.7043-x)^2+(2962424.062583-y)^2+(-6373870.064627-z)^2)-sqrt((25703029.058-x)^2+(2962107.626-y)^2+(-6370839.228-z)^2) but when using solve function [x,y,z] = solve('sqrt((20460991.052399-x)^2+(11012393.207537-y)^2+(13140061.841029-z)^2)-sqrt((20462649.31-x)^2+(11012196.356-y)^2+(13137623.266-z)^2)=31.65951', 'sqrt((1704791.07688-x)^2+(20550181.098118-y)^2+(16863812.406607-z)^2)-sqrt((1706135.95-x)^2+(20548561.881-y)^2+(16865760.323-z)^2)=243.75898', 'sqrt((18327975.818007-x)^2+(1722639.77547-y)^2+(18786981.252914-z)^2)-sqrt((18326680.829-x)^2+(1720514.194-y)^2+(18788376.839-z)^2)=-349.85327', 'sqrt((12050174.649623-x)^2+(-9980816.456693-y)^2+(21382458.132242-z)^2)-sqrt((12049062.298-x)^2+(-9983309.044-y)^2+(21381885.534-z)^2)=-575.16382', 'sqrt((6415962.553149-x)^2+(15826350.755284-y)^2+(20754833.300093-z)^2)-sqrt((6418526.123-x)^2+(15826408.315-y)^2+(20754019.037-z)^2)=441.83588', 'sqrt((18966834.575125-x)^2+(6395897.26812-y)^2+(17720969.794907-z)^2)-sqrt((18965851.475-x)^2+(6393896.947-y)^2+(17722730.048-z)^2)=-255.03605', 'sqrt((26283508.487939-x)^2+(-1051136.220342-y)^2+(4730820.234619-z)^2)-sqrt((26282933.567-x)^2+(-1051377.055-y)^2+(4733941.445-z)^2)=258.29132', 'sqrt((15456741.418182-x)^2+(19573966.047127-y)^2+(-9158923.170409-z)^2)-sqrt((15456435.97-x)^2+(19572808.522-y)^2+(-9161842.101-z)^2)=-550.04848', 'sqrt((25702282.7043-x)^2+(2962424.062583-y)^2+(-6373870.064627-z)^2)-sqrt((25703029.058-x)^2+(2962107.626-y)^2+(-6370839.228-z)^2)=549.43288')
the solution was empty x = [ empty sym ] y = [] z = []
why???????????????????/
  5 Commenti
Erik S.
Erik S. il 18 Feb 2015
Since it is an overdetermined system (more equations than variables) is it a least squars solution you need or what do you mean by solution?
ahmed ashiry
ahmed ashiry il 18 Feb 2015
i tried to solve it manually by linearized these equation using Taylor's series and then solve using least square X= inv(A'A) A' L but the results was wrong i see the probelm in manual solution is the linearization step and the large estimation process so i want to find x y z using software

Accedi per commentare.

Risposta accettata

Erik S.
Erik S. il 18 Feb 2015
Look in the documentation for the function lsqnonlin
It can solve nonlinear least squares problems.

Più risposte (0)

Categorie

Scopri di più su Systems of Nonlinear Equations in Help Center e File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by