Advanced Search

MaplePrimes Questions

invalid input: PDEtools/NumerDenom...

Asked by: LeeHoYeung 535
dsolve
September 12 2017
0  2

ode1a := diff(a(t), t) = 1.342398800*10^5*a(t)+round(89591.20000)*b(t)+round(44647.44000)*c(t);
ode2a := diff(b(t), t) = round(89591.20000)*a(t)+round(89803.24000)*b(t)+round(44901.60000)*c(t);
ode3a := diff(c(t), t) = round(44647.44000)*a(t)+round(44901.60000)*b(t)+round(44859.24000)*c(t);
sol := dsolve([ode1a=exp(t), ode2a=exp(t), ode3a=exp(t)], [a(t),b(t),c(t)]);

Error, (in dsolve) invalid input: `PDEtools/NumerDenom` expects its 1st argument, ee, to be of type algebraic, but received diff(a(t), t) = (3355997/25)*a(t)+89591*b(t)+44647*c(t)

 

initially i guess the error come from decimal number coefficient

but after round it, still have error

how to apply ricci flow?...

Asked by: LeeHoYeung 535
differential-equations eigenvalues
September 12 2017
0  0

ode1a := diff(y1(tt), tt) = 1.342398800*10^5*y1(tt)+89591.20000*y2(tt)+44647.44000*y3(tt);
ode2a := diff(y2(tt), tt) = 89591.20000*y1(tt)+89803.24000*y2(tt)+44901.60000*y3(tt);
ode3a := diff(y3(tt), tt) = 44647.44000*y1(tt)+44901.60000*y2(tt)+44859.24000*y3(tt);

would like to find the origin eigenstate before it collapse to eigenvalues

how to apply ricci flow in this situation?

i find help file , and can not find some relationship between this application and inputs of ricci related function

which functions in maple can help to find origin of eigenstate

how to deplot this case?...

Asked by: LeeHoYeung 535
plot
September 12 2017
0  3
ode1a := diff(y1(tt), tt) = 1.342398800*10^5*y1(tt)+89591.20000*y2(tt)+44647.44000*y3(tt);
ode2a := diff(y2(tt), tt) = 89591.20000*y1(tt)+89803.24000*y2(tt)+44901.60000*y3(tt);
ode3a := diff(y3(tt), tt) = 44647.44000*y1(tt)+44901.60000*y2(tt)+44859.24000*y3(tt);
 
DEplot3d({ode1a,ode2a,ode3a}, {y1(tt), y2(tt), y3(tt)}, tt=0..10,[[y1(0) = 0, y2(0) = 0, y3(0) = 0]],scene=[tt,y1(tt),y2(tt)]);
DEplot3d({ode1a,ode2a,ode3a}, {y1(tt), y2(tt), y3(tt)}, tt=0..10,[[y1(0) = 0, y2(0) = 0, y3(0) = 0]],scene=[tt,y1(tt),y3(tt)]);
DEplot3d({ode1a,ode2a,ode3a}, {y1(tt), y2(tt), y3(tt)}, tt=0..10,[[y1(0) = 0, y2(0) = 0, y3(0) = 0]],scene=[tt,y2(tt),y3(tt)]);
 
can it plot 3 functions ?
and why it return a straight line 3d graph
 
is there some interesting graph from this system?

apply while loop inside other while loop...

Asked by: shimaa sadk 50
rootfinding homework
September 12 2017
2  2


iam trying to apply newton method on non liner system but i have a problem for apply while loop inside other while loop 
any help please

> 

with(VectorCalculus):

NULL

> 

f[1] := VectorCalculus:-`+`(VectorCalculus:-`+`(VectorCalculus:-`+`(x^2, VectorCalculus:-`-`(VectorCalculus:-`*`(z, exp(y)))), VectorCalculus:-`-`(VectorCalculus:-`*`(y, exp(z)))), 61):
> 

f[2] := VectorCalculus:-`+`(VectorCalculus:-`+`(VectorCalculus:-`*`(VectorCalculus:-`*`(x, y), z), VectorCalculus:-`-`(exp(x))), -3):
> 

f[3] := VectorCalculus:-`+`(VectorCalculus:-`+`(VectorCalculus:-`+`(x^2, y^2), z^2), -14):
> 

> 

F := Matrix([[f[1]], [f[2]], [f[3]]]):
> 

FF := eval(F, [x = x[k], y = y[k], z = z[k]]):
> 

X := Matrix([[x], [y], [z]]):
> 

XX := eval(X, [x = x[k], y = y[k], z = z[k]]):
> 

J := Jacobian([f[1], f[2], f[3]], [x, y, z]):
> 

JJ := eval(J, [x = x[k], y = y[k], z = z[k]])

JJ := Matrix(3, 3, {(1, 1) = 2*x[k], (1, 2) = -z[k]*exp(y[k])-exp(z[k]), (1, 3) = -exp(y[k])-y[k]*exp(z[k]), (2, 1) = y[k]*z[k]-exp(x[k]), (2, 2) = x[k]*z[k], (2, 3) = x[k]*y[k], (3, 1) = 2*x[k], (3, 2) = 2*y[k], (3, 3) = 2*z[k]})

 (1)

``

> 

k := 0:
> 

xi := convert(exp(-10), float):
> 

maxval := 10^4:

NULL

> 

while convert(Norm(FF, 2), float) > xi do alpha[k] := min(1, alpha[k]/lambda); L := 1/JJ.FF; K := -L*alpha[k]+XX; x[k+1] := evalf(Determinant(K[1])); y[k+1] := evalf(Determinant(K[2])); z[k+1] := evalf(Determinant(K[3])); A := convert(Norm(FFF, 2), float)^2; B := convert(Norm(FF, 2), float)^2; while A > B do L := 1/JJ.FF; alpha[k+1] := lambda*alpha[k]; K := -L*alpha[k+1]+XX; x[k+1] := evalf(Determinant(K[1])); y[k+1] := evalf(Determinant(K[2])); z[k+1] := evalf(Determinant(K[3])) end do; k := k+1 end do

alpha[0] := 1

  

L := Matrix(3, 1, {(1, 1) = -(12900-300*exp(8)-1200*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(2*exp(8)+31*exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(395/2)*(7*exp(8)-4*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500), (2, 1) = (84+exp(5))*(86-2*exp(8)-8*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(5/2)*(4+exp(8)+8*exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(79/4)*(exp(8)*exp(5)+8*exp(2)*exp(5)-16*exp(8)-128*exp(2)-400)/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500), (3, 1) = -(-39+4*exp(5))*(86-2*exp(8)-8*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(5/2)*(16+2*exp(8)+exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(79/4)*(2*exp(8)*exp(5)+exp(2)*exp(5)-32*exp(8)-16*exp(2)-100)/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)})

  

K := Matrix(3, 1, {(1, 1) = 5+(12900-300*exp(8)-1200*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(2*exp(8)+31*exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(395/2)*(7*exp(8)-4*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500), (2, 1) = 8-(84+exp(5))*(86-2*exp(8)-8*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(5/2)*(4+exp(8)+8*exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)-(79/4)*(exp(8)*exp(5)+8*exp(2)*exp(5)-16*exp(8)-128*exp(2)-400)/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500), (3, 1) = 2+(-39+4*exp(5))*(86-2*exp(8)-8*exp(2))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(5/2)*(16+2*exp(8)+exp(2))*(77-exp(5))/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)+(79/4)*(2*exp(8)*exp(5)+exp(2)*exp(5)-32*exp(8)-16*exp(2)-100)/(2*exp(8)*exp(5)+31*exp(2)*exp(5)-207*exp(8)-396*exp(2)-1500)})

  

14.35960152

  

-12.24471811

  

39.82986865

  

HFloat(5.911285325999999e36)

  

35235903.22

  

Warning,  computation interrupted

  

 

 

implicit Scheme(Crank-Nicolson method)...

Asked by: sweety 5
homework pde
September 11 2017
0  2

hey... can u help me how to solve my problem using the Implicit Crank Nicolson Finite different Method. 1_ques_crank.mw..... problem in variable name A and u .. how to solve this 

 

> 

restart
> 

with(LinearAlgebra):
> 

> 

for i from 0 while i <= N+1 do u[i, 0] := 1 end do:
> 

``
> 

for i while i <= N do A[i, 0] := u[i-1, 0]+u[i+1, 0] end do:
> 

 

> 

for j from 0 while j <= N do A[0, j] := u[1, j]-.1*u[0, j]; A[10, j] := u[9, j]-.1*u[10, j] end do:
> 

 

> 

 

> 

> 

c := Matrix(10, 10, {(1, 1) = 2.1, (1, 2) = -1, (1, 3) = 0, (1, 4) = 0, (1, 5) = 0, (1, 6) = 0, (1, 7) = 0, (1, 8) = 0, (1, 9) = 0, (1, 10) = 0, (2, 1) = -1, (2, 2) = 4, (2, 3) = -1, (2, 4) = 0, (2, 5) = 0, (2, 6) = 0, (2, 7) = 0, (2, 8) = 0, (2, 9) = 0, (2, 10) = 0, (3, 1) = 0, (3, 2) = -1, (3, 3) = 4, (3, 4) = -1, (3, 5) = 0, (3, 6) = 0, (3, 7) = 0, (3, 8) = 0, (3, 9) = 0, (3, 10) = 0, (4, 1) = 0, (4, 2) = 0, (4, 3) = -1, (4, 4) = 4, (4, 5) = -1, (4, 6) = 0, (4, 7) = 0, (4, 8) = 0, (4, 9) = 0, (4, 10) = 0, (5, 1) = 0, (5, 2) = 0, (5, 3) = 0, (5, 4) = -1, (5, 5) = 4, (5, 6) = -1, (5, 7) = 0, (5, 8) = 0, (5, 9) = 0, (5, 10) = 0, (6, 1) = 0, (6, 2) = 0, (6, 3) = 0, (6, 4) = 0, (6, 5) = -1, (6, 6) = 4, (6, 7) = -1, (6, 8) = 0, (6, 9) = 0, (6, 10) = 0, (7, 1) = 0, (7, 2) = 0, (7, 3) = 0, (7, 4) = 0, (7, 5) = 0, (7, 6) = -1, (7, 7) = 4, (7, 8) = -10, (7, 9) = 0, (7, 10) = 0, (8, 1) = 0, (8, 2) = 0, (8, 3) = 0, (8, 4) = 0, (8, 5) = 0, (8, 6) = 0, (8, 7) = -1, (8, 8) = 4, (8, 9) = -1, (8, 10) = 0, (9, 1) = 0, (9, 2) = 0, (9, 3) = 0, (9, 4) = 0, (9, 5) = 0, (9, 6) = 0, (9, 7) = 0, (9, 8) = -1, (9, 9) = 4, (9, 10) = -1, (10, 1) = 0, (10, 2) = 0, (10, 3) = 0, (10, 4) = 0, (10, 5) = 0, (10, 6) = 0, (10, 7) = 0, (10, 8) = 0, (10, 9) = -1, (10, 10) = 4})
> 

C := MatrixInverse(c):
> 

for l from 0 while l <= N+1 do Known[l] := Matrix(N+1, 1, proc (i, j) options operator, arrow; A[i-1, l] end proc) end do:
> 

for l from 0 while l <= N+1 do Known[l+1] := evalm(abs(Typesetting:-delayDotProduct(C, Known[l]))) end do:
> 

``
> 

``

 


 

Download 1_ques_crank.mw

 

 

 

 

mod function help needed...

Asked by: Adam Ledger 360
mod
September 11 2017
0  8

please see attachment and explain why the output of the 2nd line is not 0
 

> 

`mod`(2*n+1, 2)

1

 (1)
> 

`mod`(2*n+1, 3)

2*n+1

 (2)
> 

`mod`(2*n, 2)

0

 (3)
> 

``


 

Download mod_maple_help.mw

Error, (in plot) unexpected options...

Asked by: n78745 5
September 11 2017
1  4

Dear all,

I'm trying to plot dispersion curves in Maple but I'm having some trouble. The code is attached as a file also.

f1  is my main function and I want to plot Vx with regard to f as all the rest are known variables, but I'm not able to do so.

I hope that someone can tell me why do I have this error.

Thanks in advance!

restart;
f1 := (C33*Rp*kzp+C13*kx)*(Rm*kx+kzm)*sin(kzp*h)*cos(kzm*h)-(C33*Rm*kzm-C13*kx)*(Rp*kx+kzp)*sin(kzm*h)*cos(kzp*h)=0;
Rp := (-C11*kx^2-C55*kzp^2+omega^2*rho)/((C55+C13)*kx*kzp);
Rm := (-C11*kx^2-C55*kzm^2+omega^2*rho)/((C55+C13)*kx*kzm);
kzp := sqrt(((-M+sqrt(M^2-4*N))*(1/2))*kx^2);
kzm := sqrt(((-M-sqrt(M^2-4*N))*(1/2))*kx^2);
M := (C11*C33/rho^2-2*C55*C13/rho^2+C13^2-omega^2*(C33+C55)/(rho*kx^2))*rho^2/(C33*C55);
N := (omega^2/kx^2-C11/rho)*(omega^2/kx^2-C55/rho)*rho^2/(C33*C55);
C11 := 0.435e10;
C13 := 0.259e10;
C55 := 0.112e10;
C33 := 0.108e11;
rho := 923;
h := 0.7e-2*(1/2);
kx := omega/Vx;
omega := 2*Pi*f;
f1;
plot(f1, f = 10 .. 0.100e6);
Error, (in plot) unexpected options: [(.4633081900*(-0.1717311166e12*f^2/Vx^2-0.2210791386e11*(...

Asim_dispers.mw

display only the +'ve x-y-z axis...

Asked by: Christopher2222 6035
September 10 2017
0  11

Display only the +'ve xyz axis, and also display +'ve axis as a different color than the negative axis.

Trouble exporting a matrix...

Asked by: tsunamiBTP 292
matrix numeric export
September 10 2017
0  4

I am having trouble exporting a matrix.  Attached is my file.  When I export the matrix the values for tpeak are not numeric.  They are string values indicating the analytical expression that MAPLE is displaying.  I cannot seem to find the option to express the results as numeric.

Can anyone help?

untitled5.mw

fsolve give me no awenser ( a blank )...

Asked by: arianbig 10
September 10 2017
0  9

i have 4 equation and 4 variables with DirectSearch package it will give me a solution but not in a good time
when i try fsolve it just give me a blank
these are my equations :
POL[0] := .42810/(.65429+c[-2])

 POL[1] := -8.4078*c[-1]-162.64*c[0]+84.228*c[1]-6/(.80888+c[-2])^2+9.7066/(.80888+c[-2])^3-3.9257/(.80888+c[-2])^4+(1/2*(.42786*c[-1]+.42786*c[0]+.42786*c[1]+.65429/(.80888+c[-2])))*(-49.180*c[-1]+31.921*c[0]-8.6921*c[1]+2/(.80888+c[-2])-3.2355/(.80888+c[-2])^2+1.3086/(.80888+c[-2])^3)

POL[2] := 53.965*c[-1]+43.012*c[0]-103.98*c[1]-6/(1.+c[-2])^2+12./(1.+c[-2])^3-6./(1.+c[-2])^4+(1/2*(.50000*c[-1]+.50000*c[0]+.50000*c[1]+1./(1.+c[-2])))*(22.229*c[-1]-37.815*c[0]+22.229*c[1]+2/(1.+c[-2])-4./(1.+c[-2])^2+2./(1.+c[-2])^3)

POL[3] := -30.115*c[-1]+43.264*c[0]+52.171*c[1]-6/(1.2363+c[-2])^2+14.836/(1.2363+c[-2])^3-9.1704/(1.2363+c[-2])^4+(1/2*(.52893*c[-1]+.52893*c[0]+.52893*c[1]+1.5284/(1.2363+c[-2])))*(-4.5997*c[-1]+16.892*c[0]-26.026*c[1]+2/(1.2363+c[-2])-4.9452/(1.2363+c[-2])^2+3.0568/(1.2363+c[-2])^3)

i even change digits to 100 but still no awenser

my fsolve syntax

K := fsolve({seq(POL[v], v = 0 .. 2*N+2)})

the awenser fsolve gave me

K:=

thats all it gave me

How do I use this procedure in odeplot?...

Asked by: awass 301
procedure numeric odeplot
September 09 2017
0  10


I want to use a variant of the arctangent function in odeplot but I run into various problems. Here is the variant called at
> at := proc (x::realcons, yy)

if 0 < x then arctan(yy/x) elif x < 0 then Pi+arctan(yy/x) elif x = 0 then (1/2)*Pi end if end proc;


It would be nice to know if this is really what I want so I try to plot at  values for which I know the answer
> plot(at(-cos(-t), sin(t)), t = 0 .. 3.14);


Error, invalid input: at expects its 1st argument, x, to be of type realcons, but received -cos(t)


I have seen this problem before so I use single quotes with success:
plot('at(-cos(-t), sin(t))', t = 0 .. 3.14);

I get the desired plot;

Now I want to use this procedure in a plot of a numerical solution to an ODE.
The ODE is quite complicated but returns a procedure ,nans, that i use to visualize solutions via commands such as


> odeplot(nans, [[y, f(y)]], y = 0 .. 6);
No problem with any of that,

The problem arise when I define theta below
> theta := at(f(y)-(1/2)*Pi, diff(f(y), y));
and try to use it in odeplot, for example,
> odeplot(nans, [[y, theta]], y = 0 .. 6);
or
> theta1:=y->at(f(y)-Pi/(2),diff(f(y),y));


> odeplot(nans, [[y, theta1(y) ]], y = 0 .. 6);


Maple's complains about theta and theta1 and all of my attempts to fix the problem:


Error, (in plots/odeplot) curve 1 is not fully specified in terms of the ODE solution, found additional unknowns {Theta1}
or
Error, (in Theta1) invalid input: at expects its 1st argument, xx, to be of type realcons, but received f1(y)-(1/2)*Pi  or


Error, (in Theta1) invalid input: diff received HFloat(0.001), which is not valid for its 2nd argument


I supect there is an easy fix. If I give up on at and just use arctan I get an ugly jump in my plot but otherwise everything works.


I am looking for a high accuracy plot, however, and the jump obscures important features.

Please help!

define a vector from 2 points...

Asked by: Christopher2222 6035
September 09 2017
2  6

Something simple. 

Two points and there doesn't seem to be an internal command to define a vector from it. 

say for example we have p=(3,6,-1) and q=(4,-2,2)

How to write pq and have the answer of q-p as a vector returned?

Project Assistance needed...

Asked by: Adam Ledger 360
http interface
September 09 2017
1  3

I have a few "regular practices" on the interface that i want to implement into conjecturing automata, and i would really really be super appreciative if i can interface it with simon's/maplsoft's inverse symbollic calculator, the only problem really is  the HTTP aspect is going  to ( im assuming) need certain information only known to the people who brought the symbolliic calc online. So thats my  question / request for help

plot/ zoom and change the axises...

Asked by: diyaco 35
plot axes scale
September 09 2017
1  2

hi

I have an equation and I want to plot this in maple.

for example, this is my equation:

w=-4.918231636*z^3+2.486861786*z^2+.8573483099*z+2.341623514

1) I want to plot z/H (H is a number) versus w so I need to switch the axises.

2) I want to plot specific area (by using commands) for example vertical axis from -0.5..0.5 and horizontal from -2..3.

i don not want to use plot property because it should be aligned for every run and it is not permanent.

thank you very much

how to find new limit equation from this clue?...

Asked by: LeeHoYeung 535
limit
September 09 2017
0  0
From clues:
a1 := subs(y=n,1/y!*x^y); # diff make it equal to the left term
a2 := subs(y=n-1,1/y!*x^y);
simplify(factor(a1 - a2));
 
To find limit of below
nterm := sum(tanh(product(sum(kk, kk=1..jj),jj=1..y))*1/y!*x^y, y=n..n);
n2term := sum(tanh(product(sum(kk, kk=1..jj),jj=1..y))*1/y!*x^y, y=(n+1)..(n+1));
simplify(factor(n2term - nterm));
simplify(limit((subs(x=x+h, n2term)-n2term)/h, h=0)) = nterm;
 
question is to find a limit make n2term equal nterm after calculation
First 941 942 943 944 945 946 947 Last Page 943 of 2434