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Question: a problem with fsolve

Question:a problem with fsolve

mehdi jafari 769 Maple
solve rootfinding fsolve heaviside
July 07 2019
1

i have a problem with a nonlinear equation containing Heaviside step function. fsolve does not return anything and SolveEquation command also returns incorrect answer. How can i solve this equation? any method or help is appreciated.


 

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restart:
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with(DirectSearch):
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F:=x*(Heaviside(x-(S0))/(1-DD)+Heaviside(-x+S0)/(1-HH*DD));

x*(Heaviside(x-S0)/(1-DD)+Heaviside(-x+S0)/(-DD*HH+1))

 (1)
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EQ:=F-E*Y;

-E*Y+x*(Heaviside(x-S0)/(1-DD)+Heaviside(-x+S0)/(-DD*HH+1))

 (2)
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HH:=0.2;
DD:=0.579350262599427;
S0:=1e8;
E:=70e9;
Y:=0.001668993263529;

.2

  

.579350262599427

  

0.1e9

  

0.70e11

  

0.1668993263529e-2

 (3)
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EQ

-116829528.5+x*(2.377274752*Heaviside(x-0.1e9)+1.131055455*Heaviside(-x+0.1e9))

 (4)
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fsolve(EQ)

fsolve(-116829528.5+x*(2.377274752*Heaviside(x-0.1e9)+1.131055455*Heaviside(-x+0.1e9)), x)

 (5)
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SolveEquations(EQ)

Warning, complex or non-numeric value encountered; trying to find a feasible point

  

[1.3868049384289111*10^13, Vector(1, {(1) = -3723983.000}), [x = 9.999999999999999*10^7], 231]

 (6)
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eval(EQ,x = 1.00000000000000*10^8)

Float(undefined)

 (7)
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