Items tagged with directsearch directsearch Tagged Items Feed

hi, the equations read as 

eq:=[2*x-0.2e-1*y-2.04*sqrt(-v^2+1)*v, 2*y-0.2e-1*x-2.16*sqrt(-u^2+1)*u, 2*u+2.16*u^2*y/sqrt(-u^2+1)-2.16*sqrt(-u^2+1)*y, 2*v+2.04*v^2*x/sqrt(-v^2+1)-2.04*sqrt(-v^2+1)*x] ;

i do as follows using DirectSearch package v.2

i find the solutions not the same,some time the results not much difference,but another,sols1 have one solution,sols2 have three solutions.in some time,some solutions are lost,the result show  me  random.may i have run the command serveral times? regards.

hello

I have a system of equation. to solve i using DirectSearch pakage. i think in answer DirectSearch use rounding number but in answer it's second and third digit after the decimal point is important. please help me. bbw.mw

if b and c increase 0.01 and -0.01 it's ok. another main question is why by increasing the intensity answer don't change.

hi

i want to use Direct Search Package for solve system of equation but i have an error:

Error, SolveEquations is not a command in the DirectSearch package.

please help me. code is attached.boltmohasebe.mw

I solve the problem on computational geometry: "A cube of side one contains two cubes of sides a and b having non-overlapping interiors. How to prove the inequality a+b≤1?" To this end I use the DirectSearch package , namely,

Here are some comments to it. The cube of side a is centered at (x_1,y_1,z_1) and rotated by the angles phi_1, psi_1, theta_1 (see http://uk.wikipedia.org/wiki/%D0%95%D0%B9%D0%BB%D0%B5%D1%80%D0%BE%D0%B2%D1%96_%D0%BA%D1%83%D1%82%D0%B8 ) and the cube of side b is centered at (x_2,y_2,z_2) and rotated by the angles phi_2, psi_2, theta_2. The procedure

calculates the distance between these cubes, for example,

st := time(); dist(.2, .9, .2, .2, .2, .7, .7, .7, 0, 0, 0, 0, 0, 0); time()-st;

[HFloat(5.453016092898238e-11), [s1 = HFloat(0.2646161775314957),

  s2 = HFloat(0.2828503247068887),

  s3 = HFloat(0.29444713116943216),

  t1 = HFloat(0.2646161774916062),

  t2 = HFloat(0.28285032471998384),

  t3 = HFloat(0.2944471311346344)], 2527]
                            191.133
Unfortunately, my code (which is syntactically correct) is spinning on my wondercomp during 10 hours without any output. I don't understand it at all. Your advices are welcome.

twocubes.mw

I want to find the greatest value of this expression 

f:=(x,y,z)->sqrt((x+1)*(y^2+2)*(z^3+3))+sqrt((y+1)*(z^2+2)*(x^3+3))+sqrt((z+1)*(x^2+2)*(y^3+3));

with x>0, y>0 , z>0,x+y+z=3.

I tried

restart:

 f:=(x,y,z)->sqrt((x+1)*(y^2+2)*(z^3+3))+sqrt((y+1)*(z^2+2)*(x^3+3))+sqrt((z+1)*(x^2+2)*(y^3+3));

DirectSearch[GlobalOptima](f(x,y,z), {x>0, y>0 , z>0,x+y+z=3},maximize);

I got the output

[HFloat(infinity), [x = .591166078050740e52, y = .183647204560715e52, z = .786638021216969e52], 1249]

 

 

hi

DirectSearch answer has confused me. How to reduce the residual.
See the program.Direct.mw

in maple 15

https://drive.google.com/file/d/0B8F2D27rfQWgVXE1alN0V3JWU1U/edit?usp=sharing

there are 3 equation to be minimized

and i limit x between x + 5 and x - 5 as constraints

 

though f1 got a error in first line of command,

later i type a correct command for f1 in later part of script

hello

please compare result of DirectSearch and implicitplot. which of them is correct??

please help me.please......

resul.mw

 

 

how i can trust in DirectSearch solution result.is there any creteria?

my variable is intensity.

this is my code:

ep0 := 1/(4*3.14); el := 8.54*10^(-2); hbar := 1; vf := 1/300; kb := 1; tem := 2.586*10^(-2); ci := 1; p := 1.458*10^16; beta := 2; ai := 7.1*10^(-4); bi := ai/sqrt(3); enph := .196; d := enph/(kb*tem); n0 := 1/(exp(enph/(kb*tem))-1); gama := hbar*vf; intensity := 10000001; w := 1.55; impurity := 7.2*10^3;

g := hbar*beta/(bi^2*sqrt(2*p*enph)); aa := g^2*(n0+1)/(2*Pi*hbar*gama^2); bb := g^2*n0/(2*Pi*hbar*gama^2); cc := 2/(Pi*gama^2); l := (1*hbar)*w/(2*kb*tem);u := el^2*intensity/(32*w*hbar^2);

 

DirectSearch:-SolveEquations([op([((enph*ln(1+exp(c+enph/(kb*tem)))/(kb*tem)-polylog(2, -exp(c))+polylog(2, -exp(c+enph/(kb*tem))))*enph*(kb*tem)^2-(enph^2*ln(1+exp(c+enph/(kb*tem)))/(kb^2*tem^2)+2*enph*polylog(2, -exp(c+enph/(kb*tem)))/(kb*tem)+2*polylog(3, -exp(c))-2*polylog(3, -exp(c+enph/(kb*tem))))*(kb*tem)^3+(-exp(b)*enph*ln(1+exp(c+enph/(kb*tem)))+exp(c+d)*enph*ln(1+exp(b-d+enph/(kb*tem)))+exp(b)*kb*tem*polylog(2, -exp(c))-exp(c+d)*kb*tem*polylog(2, -exp(b-d))-exp(b)*kb*tem*polylog(2, -exp(c+enph/(kb*tem)))+exp(c+d)*kb*tem*polylog(2, -exp(b-d+enph/(kb*tem))))*enph*(kb*tem)^2/((exp(b)-exp(c+d))*kb*tem)+(exp(b)*enph^2*ln(1+exp(c+enph/(kb*tem)))-exp(c+d)*enph^2*ln(1+exp(b-d+enph/(kb*tem)))+2*exp(b)*enph*kb*tem*polylog(2, -exp(c+enph/(kb*tem)))-2*exp(c+d)*enph*kb*tem*polylog(2, -exp(b-d+enph/(kb*tem)))+2*exp(b)*kb^2*tem^2*polylog(3, -exp(c))-2*exp(c+d)*kb^2*tem^2*polylog(3, -exp(b-d))-2*exp(b)*kb^2*tem^2*polylog(3, -exp(c+enph/(kb*tem)))+2*exp(c+d)*kb^2*tem^2*polylog(3, -exp(b-d+enph/(kb*tem))))*(kb*tem)^3/((exp(b)-exp(c+d))*kb^2*tem^2))*bb+u*(1/(1+exp(-l-c))-1/((1+exp(-l-c))*(1+exp(l-b))))-(((1*enph)*(enph-2*kb*tem*ln(1+exp(-b+enph/(kb*tem))))/(2*kb^2*tem^2)+2*kb^2*tem^2*(-polylog(2, -exp(-b+enph/(kb*tem)))+polylog(2, -cosh(b)+sinh(b))))*enph*(kb*tem)^2-(enph^2*(enph-3*kb*tem*ln(1+exp(-b+enph/(kb*tem))))-6*kb^2*tem^2*(enph*polylog(2, -exp(-b+enph/(kb*tem)))+kb*tem*(-polylog(3, -exp(-b+enph/(kb*tem)))+polylog(3, -cosh(b)+sinh(b)))))*(kb*tem)^3/(3*kb^3*tem^3)-(-exp(b)*enph^2+exp(c+d)*enph^2-2*exp(c+d)*enph*kb*tem*ln(1+exp(-b+enph/(kb*tem)))+2*exp(b)*enph*kb*tem*ln(1+exp(-c-d+enph/(kb*tem)))+2*exp(c+d)*kb^2*tem^2*polylog(2, -exp(-b))-2*exp(b)*kb^2*tem^2*polylog(2, -exp(-c-d))-2*exp(c+d)*kb^2*tem^2*polylog(2, -exp(-b+enph/(kb*tem)))+2*exp(b)*kb^2*tem^2*polylog(2, -exp(-c-d+enph/(kb*tem))))*enph*(kb*tem)^2/((2*(-exp(b)+exp(c+d)))*kb^2*tem^2)-(exp(b)*enph^3-exp(c+d)*enph^3+3*exp(c+d)*enph^2*kb*tem*ln(1+exp(-b+enph/(kb*tem)))-3*exp(b)*enph^2*kb*tem*ln(1+exp(-c-d+enph/(kb*tem)))+6*exp(c+d)*enph*kb^2*tem^2*polylog(2, -exp(-b+enph/(kb*tem)))-6*exp(b)*enph*kb^2*tem^2*polylog(2, -exp(-c-d+enph/(kb*tem)))+6*exp(c+d)*kb^3*tem^3*polylog(3, -exp(-b))-6*exp(b)*kb^3*tem^3*polylog(3, -exp(-c-d))-6*exp(c+d)*kb^3*tem^3*polylog(3, -exp(-b+enph/(kb*tem)))+6*exp(b)*kb^3*tem^3*polylog(3, -exp(-c-d+enph/(kb*tem))))*(kb*tem)^3/((3*(-exp(b)+exp(c+d)))*kb^3*tem^3))*aa-u*(1/(1+exp(l-b))-1/((1+exp(-l-c))*(1+exp(l-b)))) = 0, -cc*polylog(2, -exp(b))+cc*polylog(2, -exp(-c))-impurity = 0])], tolerances = 10^(-8), evaluationlimit = 20000)

 

hello

1-DirectSearch results is like this:

[0.,[0.], [x = -.400000000000000], 11]


x=.4 is the answer of SolveEquations (code is in the second question) please interpret other terms.

2-how can i save only x?

this is my code:

restart;

a := Matrix([1, 2, 3, 4, 5]);

for k from 1 by 1 to 5 do

z = DirectSearch:-SolveEquations(a(1, k)*x+2 = 0)

end do

 

The DirectSearch package is a powerful Maple  tool. However, every soft has its advantages and disadvantages. In particular, the DS has problems in the case of a thin feasible set in higher dimensions. Recently a serious bug in the DS was detected by me. Solving an optimization problem, the DirectSearch produces the error communication

Warning, initial point [x1 = 1., x2 = 1., x4 = 2., y1 = 2., y2 = 3., y4 = 2.] does not satisfy the inequality constraints; trying to find a feasible initial point
Error, (in DirectSearch:-Search) cannot find feasible initial point; specify a new one
 while that initial point satisfies the constraints.

 

restart

DirectSearch:-Search(((x2-x1)^2+(y2-y1)^2)*((x4-x1)^2+(y4-y1)^2), {seq(parse(y || j) >= -(2/3)*parse(x || j)+2, j = 1 .. 4), seq(parse(y || j) >= (1/2)*parse(x || j)-3/2, j = 1 .. 4), seq(parse(y || j) <= 4, j = 1 .. 4), seq(parse(y || j) <= -3*parse(x || j)+16, j = 1 .. 4), seq(parse(y || j) <= 2*parse(x || j)+2, j = 1 .. 4), (x2-x1)*(x4-x1)+(y2-y1)*(y4-y1) = 0, (x3-x2)*(x2-x1)+(y3-y2)*(y2-y1) = 0, (x4-x1)*(x4-x3)+(y4-y1)*(y4-y3) = 0, (x4-x3)*(x3-x2)+(y4-y3)*(y3-y2) = 0}, maximize, initialpoint = [x1 = 1, x2 = 1, x3 = 2, x4 = 2, y1 = 2, y2 = 3, y3 = 3, y4 = 2])

Error, (in DirectSearch:-Search) cannot find feasible initial point; specify a new one

 

eval({seq(parse(y || j) >= -(2/3)*parse(x || j)+2, j = 1 .. 4), seq(parse(y || j) >= (1/2)*parse(x || j)-3/2, j = 1 .. 4), seq(parse(y || j) <= 4, j = 1 .. 4), seq(parse(y || j) <= -3*parse(x || j)+16, j = 1 .. 4), seq(parse(y || j) <= 2*parse(x || j)+2, j = 1 .. 4), (x2-x1)*(x4-x1)+(y2-y1)*(y4-y1) = 0, (x3-x2)*(x2-x1)+(y3-y2)*(y2-y1) = 0, (x4-x1)*(x4-x3)+(y4-y1)*(y4-y3) = 0, (x4-x3)*(x3-x2)+(y4-y3)*(y3-y2) = 0}, [x1 = 1, x2 = 1, x3 = 2, x4 = 2, y1 = 2, y2 = 3, y3 = 3, y4 = 2])

{0 = 0, -1 <= 2, -1 <= 3, 2 <= 4, 2 <= 6, 2 <= 10, 2 <= 13, 3 <= 4, 3 <= 6, 3 <= 10, 3 <= 13, -1/2 <= 2, -1/2 <= 3, 2/3 <= 2, 2/3 <= 3, 4/3 <= 2, 4/3 <= 3}

(1)

``

 

Download opti.mw

Hi,

Previously I got some great help from Markiyan Hirnyk who introduced me to the DirectSearch package. I am having a little trouble implementing it for this function:

y := proc (E) options operator, arrow; -_C4*MathieuS(-a, -q, E)*(Int(MathieuC(-a, -q, E)*(-a+2*q*cos(2*E)), E))+_C4*(Int(MathieuS(-a, -q, E)*(-a+2*q*cos(2*E)), E))*MathieuC(-a, -q, E)-_C2*MathieuC(-a, -q, E)-_C3*MathieuS(-a, -q, E)-_C4*MathieuS(-a, -q, E)*MathieuCPrime(-a, -q, E)+_C4*MathieuSPrime(-a, -q, E...

Hi,

I'm using the DirectSearch package in a 10 periods model and in the first period i get this values:

"
> DirectSearch[SolveEquations](sys, assume = positive);
Warning, complex or non-numeric value encountered; trying to find a feasible point
[HFloat(1.1842542076623546e-32),

Vector[column](%id = 18446744078126621390), [

x1a = HFloat(4204.651582462925),

x1c = HFloat(4204.651582462925),

i'm using DirectSearch package to solve the following system of equations (in order to find x1a,x1c,x2a,x2c):

How can i limit the solutions just for positive values of x1a,x2a,x1c,x2c? (Currently, I'm just using  

Thanks

Gil

Hi,

how can i install the DirectSearch optimization package for mac version (MAPLE 16)? i

i have the files from maple 15.

Gil

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