Hello!

I was creating this code for the "Müller Method" for Numerical Analysis. Everything works fine till the if (for getting the x3) goes on. The problem is, the Maple doesn't detects the if.
I tried checking every variable and every variable is calculated except "x3"; even "disc".

I would like to know what happened. Anyways, here's the code:
http://imgur.com/a/DGlgl
 

                     
x0 := 0; x1 := 8.4; x2 := 10; iter := 1000; tol := 10^(-8); f := proc (x) options operator, arrow; 3*x^3+7*x^2+x+2 end proc; f(x); plot(f(x), color = green); printf(" n          x0               x1               x2              x3                Error \n"); for i to iter do d0 := evalf((f(x1)-f(x0))/(x1-x0)); d1 := evalf((f(x2)-f(x1))/(x2-x1)); h1 := evalf(x2-x1); h0 := evalf(x1-x0); a := evalf((d1-d0)/(h1-h0)); b := evalf(a*h1+d1); c := evalf(f(x2)); disc := sqrt(-4*a*c+b^2); if abs(b+disc) > abs(b-disc) then x3 := x2+(-2*c)*(1/(b+sqrt(-4*a*c+b^2))); erry := abs((x3-x2)/x3) else x3 := x2+(-2*c)*(1/(b-sqrt(-4*a*c+b^2))); erry := abs((x3-x2)/x3) end if; if erry > tol then x0 := x1; x1 := x2; x2 := x3; printf("%2d     %2.8f      %2.8f       %2.8f         %2.5 f     %2.8 f \n", i, a, b, c, x3, erry) else printf("una raiz es: %2.8f ", x3); break end if end do;

I put the image (as it looks on my maple) and the "code" so you can copy-paste it in Maple.

Dear hope you will be fine I want to represent the data in term of solid line not dotted, asterik etc of the following code. Please help me to fix this problem

restart; epsilon := 0; Pr := 1; beta := .1; Sc := 1; S := 0; L := 15;
                               15
for i from -L while i <= L do a[i] := 1.0*i/L end do;
for i2 from -L while i2 <= L do fw := a[i2]; Eq1[i2] := eval(diff(F(eta), eta, eta, eta)+F(eta)*(diff(F(eta), eta, eta))-(diff(F(eta), eta))^2+S*(epsilon-(diff(F(eta), eta)))+epsilon^2); Eq2[i2] := eval((diff(G(eta), eta, eta))/Pr-G(eta)*(diff(F(eta), eta))+F(eta)*(diff(G(eta), eta))); Eq3[i2] := eval(diff(H(eta), eta, eta)+Sc*(F(eta)*(diff(H(eta), eta))-beta*H(eta))); IC[i2] := F(0) = a[i2], (D(F))(0) = 1, (D(F))(L) = epsilon, G(0) = 1, G(L) = 0, H(0) = 1, H(L) = 0; dsys1[i2] := {Eq1[i2], Eq2[i2], Eq3[i2], IC[i2]}; dsol1[i2] := dsolve(dsys1[i2], numeric, output = listprocedure, range = 0 .. L); dsol1x[i2] := subs(dsol1[i2], diff(F(eta), eta, eta)); dsol1y[i2] := subs(dsol1[i2], G(eta)); dsol1z[i2] := subs(dsol1[i2], H(eta)) end do;
for j from -L while j <= L do g[j] := eval(-dsol1x[j](0)) end do;
with(plots);

g1 := pointplot({seq([n/L, g[n]], n = -L .. L)}, symbol = asterisk, symbolsize = 15, color = blue);
display(g1);
 

Hello everyone,

I have 5 equations (fa,fb,fc,fk,fv) and 5 variables (V0,A0,A1,A2,k1) and I want to solve them numerically. Problem is my inability to set properly intervals and starting values. 

Here is my command: fsolve({fa,fb,fc,fk,fv},{V0,A0,A1,A2,k1});

If I run it just like this, I get some values, lets say V0=0.00045 etc.But when I set range for V0 like this:

fsolve({fa,fb,fc,fk,fv},{V0=0.0004..0.0005,A0,A1,A2,k1});

I get this:

Error, (in fsolve) fsolve cannot solve on V0 = 0.4e-3 .. 0.5e-3

I used interval 0.0004..0.0005 only to prove that there must be the wrong syntax, because obviously 0.0004<0.00045<0.0005. In reality i need interval 0.0001..0.0002 and it is also necessary.to set some initial values (A0=0.0023) but first I need to solve my problem with syntax.

Any advice ?

hello i have the following set of ode's:

ode_sub := diff(S(t), t) = -k1*S(t)-S(t)/T1_s;
ode_P1 := diff(P1(t), t) = k1*S(t)-k2*(P1(t)-P2(t)/keq)-P1(t)/T1_p1;
ode_P2 := diff(P2(t), t) = -k2*(-keq*P1(t)+P2(t))/keq-k4*P2(t)-P2(t)/T1_p2;
ode_P2e := diff(P2_e(t), t) = k4*P2(t)-P2_e(t)/T1_p2_e;

ode_system := ode_sub, ode_P1, ode_P2, ode_P2e;

with these parameters:
s0 := 10000;
k2 := 1000; T1_s := 14; T1_p2_e := 35; T1_p2 := T1_p1;
 

i want to find the unkown parameters : T1_p1, k1, keq and k4

my idea was this:

init:=S(0)=s0,P1(0)=0,P2(0)=0,P2_e(0)=0

dsolve({ode_system,init})

sol := combine(expand(%));
PS := subs(sol, [S(t), P1(t), P2(t), P2_e(t)]);
 

P1fu := unapply(PS[2],t);
Sfu := unapply(PS[1],t);
P2fu := unapply(PS[3],t);
P2e_fu := unapply(PS[4],t);
P2_total := unapply(P2fu+P2e_fu, t);
 

the following data is given:

T:=<0,2,4,6,8>

S:=<9999.99913146527,8328.870587730016,6937.009129218748,5777.745632133724,4812.209983843559>

P1:=<0.0,67.86790056712294,114.88787098501874,145.95438088662502,164.85650644237887>

P2_P2e:=<0.0,271.68492651947497,461.9130396605823,589.3710176125417,668.9967533337124> # data from P2(t)+P2_e(t)

making the rediduals:

RP1 := convert(P1-P1fu~(T), list);
RS := convert(S-Sfu~(T), list);
RP2_P2e := convert(P2_P2_e-P2_total~(T), list);
 

RPs := [op(RS), op(RP2_P2_e), op(RP1)]

res := Optimization:-LSSolve(RPs, k1 = 0 .. 1, keq = 0 .. 10, k4 = 0 .. 1, T1_p1 = 0 .. 100)

i dont know wheter or not the last step work to get the parameters becuase it takes to long to compute. is there a smarter way to obtain the parameters of the ode's? a numeric approch ?

i tried with dsolve({ode_sysytem,init},numeric,'parameters'=[k1,keq,k4,T1_p1]) however it doesnt seem to get my anywhere since i need to know the parameters to use this (i think)

hope someone can help:)

Hello everyone,

I am making a mobile robot simulation in the MapleSim environment and I need to create varriable (uneven) terrain, do I need an additional library for that?

If not how can I do so?

Thanks for your time!

John

how to convert a^2*b+c to func2(func1(func1(abc[1],abc[1]),abc[2]),abc[3])

when i use custom function func2 to represent plus, func1 to represent multiply

input 3 parameters,

one is a^2*b + c one is [func1, func2] and second is [abc[1],abc[2],abc[3]] corresponding to a, b, c
a^2*b + c = func2(func1(func1(abc[1],abc[1]),abc[2]),abc[3]);

This is simplified from a larger example.  I never saw Maple exit from a numercal calculation.

> 123456789 ^ 987654321:
Execution stopped: Stack limit reached.

Process Maple R2016 exited abnormally with code 158

> kernelopts(maxdigits);
                                  38654705646

> lprint(123456789. ^ 987654321.);
.4339566080e7991619731

kernelopts(memusage) shows about 2~3 meg bytes used.

The system has 16G Ram.  16G swap.

Seems like something maple should have caught.

I need help to create a program that will find all the positive integers n, where n < 1000, such that
(n 􏰀-1)!= 􏰁 􏰀-1 (mod n^2 ) . program has to be in full and state the values of n obtained. 

Try solve 

restart; with(PDEtools);
U := diff_table(u(x, y, z));

pde[1] := x*y*U[z]+x*U[x]+2*y*U[y] = 0;

bc[1] := eval(U[], z = 0) = x^2+y^2;
sys[1] := [pde[1], bc[1]];
pdsolve(sys[1])

Maple nothing returned. Where my mistake ?? Thank you.

Hi

We solve the following ode in the interval (0,Pi):

 diff(u(x),x,x)+u(x)=f(x);

bcs=u(0)=0, u(Pi)=0;

Stating one example of many conditions for such equation to have a
valid solution

Many thanks

restart;
eq1 := T - M*g = 0;
eq2 := T1*sin(theta1) + T2*sin(theta2) - T = 0;
eq3 := -T1*cos(theta1) + T2*cos(theta2) = 0;
soln := solve({eq1,eq2,eq3},{T,T1,T2});

limit(subs(theta2=theta1,soln[3]),theta1=0);

This returns a limit -> ... expression.  Since there is a sin(theta1) in the denominator, this should be undefined or infinity.

I am tryng to change variables in multiple integral as below, but receive error. Help me to do so.
 

Download inttt.mw

I don't know where to ask this.  Sorry if this is the wrong forum.

I use maplev-mode

;; Version:    2.155
;; X-RCS:      $Id: maplev.el,v 1.14 2006-06-02 14:02:38 joe Exp $
 

I am attempting to modify it so
  f1 invokes maplev-cmaple-send-line
  f2 invokes maplev-cmaple-send-region
  f3 invokes maplev-cmaple-send-buffer
 

tried adding
(define-key map [(control c) (control c) ?l] 'maplev-cmaple-send-line)
(define-key map [(f1)]  'maplev-cmaple-send-line)

but, emacs seems to not recognize this.  I can change the global keymap to get this behavior.
Is there a way to do this in maplev.el?
 

Tom Dean

Hey everyone!

My question is pretty straightforward: I have a second degree tensor and I need a fourth degree order one from it.

In Python, there is a command that performs the action, would there be one in Maple? Or any kind of process to go through to get the result?

Thanks

My code :

> restart; with*PDEtools;

> PDE := diff(u(x, t), `$`(t, 2)) = 4*(diff(u(x, t), `$`(x, 2)));

> pdsolve({PDE, u(x, 0) = cos((1/2)*x), (D[1](u))(x, 0) = 0}, u(x, t));
 

And i get Error, (in pdsolve/BC) invalid input: indets expects 1 or 2 arguments, but received 3.Please help me find my Error.Thank you!!!