Maple Questions and Posts

These are Posts and Questions associated with the product, Maple

have table like table(symmetric, [() = x]) from other code not mine, strange syntax

how to extract x from table thanks

I have the following code. I want to do the modify it so that:

1. The outputs of each for loop are merged in such a way that the outputs from the first loop (Es) that are also outputs of the second loop (Fs) are removed from the outputs of (Es).

2. The resulting outputs G= .... are saved to a text file, one to each line.

3. In between each output, I want to add 5 lines of text and a blank line, say

text1 text2 text3

text2 text2 text3

text3 text3 text3

text4 text4 text4

text5 text5 text5

(blank line)

so that in the text file, the format is (e.g.)

G={{1,2}};

text1 text2 text3

text2 text2 text3

text3 text3 text3

text4 text4 text4

text5 text5 text5

(blank line)

G={{1,2},{1,3}};

text1 text2 text3

text2 text2 text3

text3 text3 text3

text4 text4 text4

text5 text5 text5

(blank line)

etc.

What is the easiest way to accomplish this?

restart;
 
with(GraphTheory):
 n:= 4:
  L:= NonIsomorphicGraphs
      ( n,
        output=iterator,
        outputform=graph):
  Es:= Array
       ( [ seq
           (  Edges( L() ),
              j=1..NonIsomorphicGraphs
                   ( n,
                     output=count
                   )
           )
         ]
       ):


  M:= NonIsomorphicGraphs
      ( n-1,
        output=iterator,
        outputform=graph):
  Fs:= Array
       ( [ seq
           (  Edges( M() ),
              j=1..NonIsomorphicGraphs
                   ( n-1,
                     output=count
                   )
           )
         ]
       ):
;

numelems(Es): 
for i from 1 to numelems(Es) do G:=Es[i]:  od;
                           
numelems(Fs):
for i to numelems(Fs) do G := Fs[i]; od;
                        

Hey everyone ! 

I want to get the analytical function from a piecewise differential equation defined on 6 intervals but Maple returns me a numerical result... I think it hides a Runge Kutta method.. However, it returned me an analytical function for a similar piecewise differential equation defined on 3 intervals.

Do you know how I could get the analytical function defined on the 6 intervals ?

Thank you very much for your time ! 

Alex

eq := diff(Uy(x), x, x)-piecewise(x < d1, 12*F*x/(E*b*h^3), d1 < x and x < d2, 12*((F+F1)*x-F1*d1)/(E*b*h^3), d2 < x and x < d3, 12*((F+F1+F2)*x-F1*d1-F2*d2)/(E*b*h^3), d3 < x and x < d4, 12*((F5+F4-F)*x+F*L-F5*d5-F4*d4)/(E*b*h^3), d4 < x and x < d5, 12*((F5-F)*x+F*L-F5*d5)/(E*b*h^3), 12*F*(L-x)/(E*b*h^3))

diff(diff(Uy(x), x), x)-piecewise(x < d1, 12*F*x/(E*b*h^3), d1 < x and x < d2, 12*((F+F1)*x-F1*d1)/(E*b*h^3), d2 < x and x < d3, 12*((F+F1+F2)*x-F1*d1-F2*d2)/(E*b*h^3), d3 < x and x < d4, 12*((F5+F4-F)*x+F*L-F5*d5-F4*d4)/(E*b*h^3), d4 < x and x < d5, 12*((F5-F)*x+F*L-F5*d5)/(E*b*h^3), 12*F*(L-x)/(E*b*h^3))

(1)

dsolve({eq, Uy(0) = 0, Uy(L) = 0}, Uy(x))

assign(dsolve({eq, Uy(0) = 0, Uy(L) = 0}, Uy(x)))

Uy_sol := unapply(Uy(x), x)

proc (x) options operator, arrow; Uy(x) end proc

(2)

E := 210*10^9; L := 4; d1 := (1/6)*L; d2 := 2*L*(1/6); d3 := 3*L*(1/6); d4 := 4*L*(1/6); d5 := 5*L*(1/6); b := 0.1e-1; h := 0.5e-2

210000000000

 

4

 

2/3

 

4/3

 

2

 

8/3

 

10/3

 

0.1e-1

 

0.5e-2

(3)

eq

diff(diff(Uy(x), x), x)-piecewise(x < 2/3, 0.4571428572e-1*F*x, 2/3 < x and x < 4/3, 0.4571428572e-1*(F+F1)*x-0.3047619048e-1*F1, 4/3 < x and x < 2, 0.4571428572e-1*(F+F1+F2)*x-0.3047619048e-1*F1-0.6095238096e-1*F2, 2 < x and x < 8/3, 0.4571428572e-1*(F5+F4-F)*x+.1828571429*F-.1523809524*F5-.1219047619*F4, 8/3 < x and x < 10/3, 0.4571428572e-1*(F5-F)*x+.1828571429*F-.1523809524*F5, 0.4571428572e-1*F*(4-x))

(4)

dsolve({eq, Uy(0) = 0, Uy(L) = 0}, Uy(x))

Uy(x) = -(1/4)*(Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. 4))*x+Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. x)

(5)

Uy(x)[0]

Uy(x)[0]

(6)

assign(dsolve({eq, Uy(0) = 0, Uy(L) = 0}, Uy(x)))

Uy(x)[0]

(-(1/4)*(Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. 4))*x+Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. x))[0]

(7)

Uy(x < d1)

Uy(x < 2/3)

(8)

Uy(x)[x < d1]

(-(1/4)*(Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. 4))*x+Int(Int(piecewise(_z1 < 2/3, (1142857143/25000000000)*F*_z1, _z1 < 4/3, (1142857143/25000000000)*F*_z1-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1, _z1 < 2, (1142857143/25000000000)*F*_z1-(380952381/6250000000)*F2-(380952381/12500000000)*F1+(1142857143/25000000000)*F1*_z1+(1142857143/25000000000)*_z1*F2, _z1 < 8/3, -(1142857143/25000000000)*F*_z1-(1219047619/10000000000)*F4-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*F4*_z1+(1142857143/25000000000)*_z1*F5, _z1 < 10/3, -(1142857143/25000000000)*F*_z1-(380952381/2500000000)*F5+(1828571429/10000000000)*F+(1142857143/25000000000)*_z1*F5, 10/3 <= _z1, -(1142857143/25000000000)*F*_z1+(1142857143/6250000000)*F), _z1 = 0 .. _z1), _z1 = 0 .. x))[x < 2/3]

(9)

NULL

Download cas_5v_F_inconnues.mw

restart; N := 100; dx := evalf(2*Pi/N)

100

 

0.6283185308e-1

(1)

f1 := proc (x) options operator, arrow; sin(x) end proc;

proc (x) options operator, arrow; sin(x) end proc

(2)

DiscX := proc (N, dx) local i, xv; xv := Vector(N); for i to N do xv[i] := evalf((i-(1/2)*N-1)*dx) end do; return xv end proc:

Xfun := proc (f1) local i, xa1, xa2; xa1 := Vector(N); xa2 := Vector(N); for i to N do xa1[i] := evalf(subs(x = a[i], f1(x))) end do; return xa1 end proc:

IntNum := proc (N, a, c) local i, xv1; xv1 := Vector(N); for i from 2 to N-1 do xv1[i] := evalf((1/2)*(a[i]-a[i+1])*(c[i]+c[i+1])) end do; return xv1 end proc:

a := DiscX(N, dx); a[1]; a[100]

a := Vector(4, {(1) = ` 1 .. 100 `*Vector[column], (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

 

-3.141592654

 

3.078760801

(3)

c := Xfun(f1); c[1]

c := Vector(4, {(1) = ` 1 .. 100 `*Vector[column], (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

 

0.4102067615e-9

(4)

k := IntNum(N, a, c)

k := Vector(4, {(1) = ` 1 .. 100 `*Vector[column], (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

(5)

plot([seq([a[i], k[i]], i = 2 .. N)], style = line, title = typeset("Integ_of_sin(x)"), titlefont = [times, bold, 30]);

 

``

Download test.mw

Hey everyone!

I would like to plot the integral of a discrete function. For simplicity, I choose the function sin(x) between –Pi and Pi, which has as an integral -cos(x). I tried to implement that in Maple using the Trapezoidal rule, but the result is simply wrong. Any help would be much appreciated!

I have the following Maplesoft code:

with(ImageTools);

with(IterativeMaps):
Crystal, xrange, yrange := Attractor([x, y], [[1/2 - y/2, x/2], [y/2 + 1/2, 1/2 - x/2], [x/2 + 1/4, y/2 + 1/2]], height = 400, width = 400, xmin = -1, xmax = 2, ymin = -1, ymax = 1, fixview = true, [0, 0], [0.33, 0.33, 0.33], greenexpression = 1 - 1/(1/(1 - G) + 1), iterations = 2500000);
xrange, yrange;
                        -1 .. 2, -1 .. 1

ColouringProcedures:-HueToRGB(Crystal);
                               0.

Embed(Crystal);

which yields the following image:


However, I should be seeing the following image:

Any help would be appreciated. Thanks!

Justify that 2 vectors (1,1) and (1,2) are an R² base; How to write calculations correctly ?
<x, y> = lambda*<1, 1> + mu*<1, 2>:
 solve({lambda+mu=x,lambda+2*mu=y},{lambda,mu}):
 <x, y> := (2*x - y)*<1, 1> + (-x + y)*<1, 2>:
Thank you.

I get this error when I try to use the ODE numeric solver, can anybody help me figure out what Im doing wrong? 

hi guys,

I have a question about computing reimann tensor in general relativity.

suppose we have schwarzschidl metric: ds^2=-(1-2*m*(r^-1))*dt^2+(1-2*m*(r^-1))^(-1)*dr^2+r^2*dtheta^2+r^2*sin^2(theta)*dphi^2.

I want to caclulate R[alpha,beta,mu,nu]*R[~alpha,~beta,~mu,~nu] where R[alpha,beta,mu,nu] is covariant form of Reimann tensor and also R[~alpha,~beta,~mu,~nu] is the contravariant form of Riemann tensor. I also want to calculate same thing for weyl tensor. please guide me.

with best regards.

A simple suggestion...

I would appreciate being able to open multiple help pages simultaneously instead of just one.
This seems to me particularly interesting when you have to browse back and forth between several related items.

How to reconstruct commutators like for example in Drinfeld associators (see (4.5) in https://arxiv.org/pdf/1310.3259.pdf)?

We have as computed in Drinfieldstuff_display.mw (note to run this it requires loading HyperInt package https://arxiv.org/pdf/1403.3385.pdf):

H[2] := a^2*(e[0]*e[1] - e[1]*e[0])*zeta[2]

H[3] := zeta[3]*a^3*(((e[0]*e[1]^2 + e[0]^2*e[1] - (2*e[1])*e[0]*e[1]) + e[1]^2*e[0]) - (2*e[0])*e[1]*e[0] + e[1]*e[0]^2)

H[4] := zeta[2]^2*a^4*((((((4*e[0])*e[1]^3 + (12*e[0])*e[1]*e[0]^2 - (5*e[1])*e[0]^2*e[1] - (4*e[1])*e[0]^3) - (4*e[1]^3)*e[0]) + (7*e[1])*e[0]*e[1]*e[0] + (12*e[1]^2)*e[0]*e[1] + (3*e[0])*e[1]*e[0]*e[1] - (12*e[0]^2)*e[1]*e[0] - (5*e[0])*e[1]^2*e[0] + e[0]^2*e[1]^2 - (12*e[1])*e[0]*e[1]^2) - e[1]^2*e[0]^2) + (4*e[0]^3)*e[1])/10

And we want maple rebuild them as  commutators as below ([x,y]=xy-yx). Correspondingly:

H[2] :=zeta[2] [e[0] , e[1] ]

H[3] :=zeta[ 3] ( [e[0] , [e[0], e[1] ]] − [e[1] , [e[0] , e[1] ]] )

H[4] :=zeta[4] [e[0] , [e[0], [e[0] , e[1]]]] −1/4* [e[0] , [e[1] , [e[0] ,e[1] ]]] + [e[1] , [e[1] , [e[0] , e[1] ]]] + 5/4*[e[0], e[1]] ^2

Does anyone know how to do it?

In the plotting guide I didn't see a waterfall chart so I created a procedure. 
If anyone has a more efficent, better or alternate way please feel free to add.


 

waterfall := proc (data, colorinc := green, colordec := red) local i, r1; r || 1 := plots:-display(plottools:-rectangle([0, 0], [1, data[1]]), color = colorinc); for i from 2 to nops(data) do if data[i-1] < data[i] then r || i := plots:-display(plottools:-rectangle([i-1, data[i-1]], [i, data[i]]), color = colorinc) elif data[i] < data[i-1] then r || i := plots:-display(plottools:-rectangle([i-1, data[i-1]], [i, data[i]]), color = colordec) else r || i := plots:-display(plottools:-rectangle([i-1, data[i-1]], [i, data[i]])) end if end do; plots:-display(seq(r || i, i = 1 .. nops(data))) end proc
``

data := [6, 4, 4, 4, 7, 9, 12, 16, 25, 100, 105, 95, 90, 55, 45, 30]

[6, 4, 4, 4, 7, 9, 12, 16, 25, 100, 105, 95, 90, 55, 45, 30]

(1)

waterfall(data)

 

waterfall(data, purple, yellow)

 

``


 

Download Waterfall.mw

 

Hi

I got the error like this unable to convert to an explicit first-order system

please anyone can help me to solve this

I am attaching the worksheet

with(plots); restart

eq1 := (2*eta*gamma+1)*(diff(f(eta), `$`(eta, 3)))+2*gamma*(diff(f(eta), `$`(eta, 2)))+f(eta)*(diff(f(eta), `$`(eta, 2)))-(diff(f(eta), eta))^2-(Q+S)*(diff(f(eta), eta))+beta*(diff(F(eta), eta)-(diff(f(eta), eta))) = 0;

(2*eta*gamma+1)*(diff(diff(diff(f(eta), eta), eta), eta))+2*gamma*(diff(diff(f(eta), eta), eta))+f(eta)*(diff(diff(f(eta), eta), eta))-(diff(f(eta), eta))^2-(Q+S)*(diff(f(eta), eta))+beta*(diff(F(eta), eta)-(diff(f(eta), eta))) = 0

(1)

eq2 := (diff(F(eta), `$`(eta, 2)))*F(eta)-(diff(F(eta), eta))^2+beta*(diff(f(eta), eta)-(diff(F(eta), eta))) = 0;

(diff(diff(F(eta), eta), eta))*F(eta)-(diff(F(eta), eta))^2+beta*(diff(f(eta), eta)-(diff(F(eta), eta))) = 0

(2)

eq3 := (2*eta*gamma+1)*(1+Rd)*(diff(theta(eta), `$`(eta, 2)))+Pr*((diff(theta(eta), eta))*f(eta)-2*(diff(f(eta), eta))*theta(eta))+gamma*(diff(theta(eta), eta))+N*Pr*betat*((theta[p](eta), eta)-theta(eta))+N*Pr*Ec*betat*(diff(F(eta), eta)-(diff(f(eta), eta)))+Pr*delta*theta(eta) = 0;

(2*eta*gamma+1)*(1+Rd)*(diff(diff(theta(eta), eta), eta))+Pr*((diff(theta(eta), eta))*f(eta)-2*(diff(f(eta), eta))*theta(eta))+gamma*(diff(theta(eta), eta))+N*Pr*betat*((theta[p](eta), eta)-theta(eta))+N*Pr*Ec*betat*(diff(F(eta), eta)-(diff(f(eta), eta)))+Pr*delta*theta(eta) = 0

(3)

eq4 := 2*(diff(theta[p](eta), eta))*f(eta)-F(eta)*theta[p](eta)+betat*delta*(theta[p](eta)-theta(eta)) = 0;

2*(diff(theta[p](eta), eta))*f(eta)-F(eta)*theta[p](eta)+betat*delta*(theta[p](eta)-theta(eta)) = 0

(4)

bcs := f(0) = 0, (D(f))(0) = 1, (D(f))(5) = 0, (D(F))(5) = 0, F(5) = f(5), theta(0) = 1, theta(5) = 0, theta[p](5) = 0;

f(0) = 0, (D(f))(0) = 1, (D(f))(5) = 0, (D(F))(5) = 0, F(5) = f(5), theta(0) = 1, theta(5) = 0, theta[p](5) = 0

(5)

params := [Rd = .1, beta = .5, Q = .5, S = .5, gamma = .1, Pr = 6.2, N = .5, betat = .5, Ec = .1];

[Rd = .1, beta = .5, Q = .5, S = .5, gamma = .1, Pr = 6.2, N = .5, betat = .5, Ec = .1]

(6)

sol := dsolve(eval([eq1, eq2, eq3, eq4, bcs], params), numeric, output = array([0]), maxmesh = 5000, initmesh = 1000)

Error, (in dsolve/numeric/bvp/convertsys) unable to convert to an explicit first-order system

 

``

Download MapleOde.mw

Hi,

I try to display a different steps of an mathematical developpement with ShowSteps command, but But the command gives nothing in the new version Maple 2021?

Thanks for your Help

QShowSteps.mw

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