509 Reputation

12 years, 115 days

Is true or false: Pi < 0...

Maple 14

Hi,

I have this procedure:

f := proc(x) if x < 0 then x^2+1; else cos(x); end if; end proc:

When I calculate NLPSolve(f,-Pi..2*Pi); the result is good. In NLPSolve, f(Pi) or f(-Pi) are also calculated.

When I want to determine f(Pi), I have this error code:

Error, (in f) cannot determine if this expression is true or false: Pi < 0

Why ?

I must change my procedure with adding "evalf" to get a result for f(Pi):...

My problem in optimization...

Hi

It is not corect in my problem to get different parameters a, b, c, ... for fmin, fmax and the objective function.

The probleme is to minimize the objective function (fmax-fmin)/fmoy.

NLPSolve((fmax-fmin)/fmoy,t = 0 .. Pi/p/wr,a=1..5,b=0.1..0.5,c=0.4..0.8,d=10..20,wr=200..300,p=5..20);...

Optimization with NLPSolve...

Maple 14

Hi

The example below is the same as my code:

restart:with(Optimization):f:=(a+2*b+c*d)*sin(wr*p*t);

fmoy := p*wr*(int(f, t = 0 .. Pi/p/wr))/Pi;

fmax:=NLPSolve(f,t = 0 .. 2,a=1..5,b=0.1..0.5,c=0.4..0.8,d=10..20,wr=200..300,p=5..20,maximize);

fmin:=NLPSolve(f,t = 0 .. 2,a=1..5,b=0.1..0.5,c=0.4..0.8,d=10..20,wr=200..300,p=5..20);

Taux:=NLPSolve((fmax-fmin)/fmoy,t = 0 .. 2,a=1..5,b=0.1..0.5,c=0.4..0.8,d=10..20,wr=200..300,p=5..20);

Manipulating Matrices...

Maple 14

Hi

I have some difficulties in manipulating matrices in Maple

For example, I have a matrice with 40 rows and 9 columns ans I want to extract the odd rows taking columns inchanged. The new matrice which has 20 rows and 9 columns must replace the old matrice

In Matlab, I do this with only one command: WTable=WTable(1:2:40,:);