MaplePrimes Questions

I have a problem with IsMatrixShape. I have in my part of formulation this matrix expression: QTIbQ

While Ib is a symmetric matrix, this matrix expression is clearly symmetric. However, when I try to check this issue with IsMatrixShape command, it returns false. I am extremely confused. Can anyone help me? Thanks in advance.

prob1.mw    prob2.mw

Hi, I don't know why this happened...

If I write the command in new sheet, it runs correctly( prob2.mw).

 

Second, help me to evaluate N, please...  (prob1.mw)

 

Regards :-)

 

 

 

 

 


restart; with(Physics); with(Tetrads); with(PDETools)

0, "%1 is not a command in the %2 package", Tetrads, Physics

(1)

coords := zetabar, zeta, v, u

zetabar, zeta, v, u

(2)

X = [coords]

X = [zetabar, zeta, v, u]

(3)

ds2 := Physics:-`*`(Physics:-`*`(2, dzeta), dzetabar)+Physics:-`*`(Physics:-`*`(2, du), dv)+Physics:-`*`(Physics:-`*`(2, H(coords)), Physics:-`^`(du+Physics:-`*`(Ybar(coords), dzeta)+Physics:-`*`(Y(coords), dzetabar)-Physics:-`*`(Physics:-`*`(Y(coords), Ybar(coords)), dv), 2))

2*dzeta*dzetabar+2*du*dv+2*H(zetabar, zeta, v, u)*(du+Ybar(zetabar, zeta, v, u)*dzeta+Y(zetabar, zeta, v, u)*dzetabar-Y(zetabar, zeta, v, u)*Ybar(zetabar, zeta, v, u)*dv)^2

(4)

PDEtools:-declare(ds2)

Ybar(zetabar, zeta, v, u)*`will now be displayed as`*Ybar

(5)

vierbien := Matrix([[1, 0, -Ybar(coords), 0], [0, 1, -Y(coords), 0], [Physics:-`*`(H(coords), Y(coords)), Physics:-`*`(H(coords), Ybar(coords)), 1-Physics:-`*`(Physics:-`*`(H(coords), Y(coords)), Ybar(coords)), H(coords)], [Y(coords), Ybar(coords), -Physics:-`*`(Y(coords), Ybar(coords)), 1]])

vierbien := Matrix(4, 4, {(1, 1) = 1, (1, 2) = 0, (1, 3) = -Ybar(zetabar, Zeta, v, u), (1, 4) = 0, (2, 1) = 0, (2, 2) = 1, (2, 3) = -Y(zetabar, Zeta, v, u), (2, 4) = 0, (3, 1) = H(zetabar, Zeta, v, u)*Y(zetabar, Zeta, v, u), (3, 2) = H(zetabar, Zeta, v, u)*Ybar(zetabar, Zeta, v, u), (3, 3) = 1-H(zetabar, Zeta, v, u)*Y(zetabar, Zeta, v, u)*Ybar(zetabar, Zeta, v, u), (3, 4) = H(zetabar, Zeta, v, u), (4, 1) = Y(zetabar, Zeta, v, u), (4, 2) = Ybar(zetabar, Zeta, v, u), (4, 3) = -Y(zetabar, Zeta, v, u)*Ybar(zetabar, Zeta, v, u), (4, 4) = 1})

(6)

``

Physics:-Setup(coordinatesystem = (X = [zetabar, zeta, v, u]), metric = ds2, tetrad = vierbien, mathematicalnotation = true, automaticsimplification = true, signature = "+++-")

RicciT := proc (a, b) options operator, arrow; Physics:-SumOverRepeatedIndices(Ricci[mu, nu]*e_[a, `~mu`]*e_[b, `~nu`]) end proc

proc (a, b) options operator, arrow; Physics:-SumOverRepeatedIndices(Physics:-`*`(Physics:-`*`(Physics:-Ricci[mu, nu], Physics:-Tetrads:-e_[a, `~mu`]), Physics:-Tetrads:-e_[b, `~nu`])) end proc

(7)

SlashD := proc (f, a) options operator, arrow; Physics:-SumOverRepeatedIndices(Physics:-D_[mu](f)*e_[a, `~mu`]) end proc

proc (f, a) options operator, arrow; Physics:-SumOverRepeatedIndices(Physics:-`*`(Physics:-D_[mu](f), Physics:-Tetrads:-e_[a, `~mu`])) end proc

(8)

SlashD(H(X), 4) = H(X)[4]

(diff(H(X), zetabar))*Ybar(X)+(diff(H(X), zeta))*Y(X)+diff(H(X), v)-(diff(H(X), u))*Y(X)*Ybar(X) = H(X)[4]

(9)

Gamma := proc (a, b, c) options operator, arrow; -gamma_[a, b, c] end proc

proc (a, b, c) options operator, arrow; Physics:-`*`(Physics:-Tetrads:-gamma_[a, b, c], -1) end proc

(10)

Gamma(1, 4, 4) = 0

-(diff(Ybar(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Ybar(X), zeta))+Ybar(X)*(diff(Ybar(X), zetabar))+diff(Ybar(X), v) = 0

(11)

``

Gamma(2, 4, 4) = 0

-(diff(Y(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Y(X), zeta))+(diff(Y(X), zetabar))*Ybar(X)+diff(Y(X), v) = 0

(12)

``

Gamma(3, 4, 4) = 0

0 = 0

(13)

``

Gamma(4, 4, 4) = 0

0 = 0

(14)

Gamma(4, 1, 1) = 0

-(diff(Ybar(X), zeta))+(diff(Ybar(X), u))*Ybar(X) = 0

(15)

``

Gamma(4, 2, 2) = 0

-(diff(Y(X), zetabar))+(diff(Y(X), u))*Y(X) = 0

(16)

NULL

shearconditions := {-(diff(Y(X), zetabar))+(diff(Y(X), u))*Y(X) = 0, -(diff(Ybar(X), zeta))+(diff(Ybar(X), u))*Ybar(X) = 0, -(diff(Y(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Y(X), zeta))+(diff(Y(X), zetabar))*Ybar(X)+diff(Y(X), v) = 0, -(diff(Ybar(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Ybar(X), zeta))+Ybar(X)*(diff(Ybar(X), zetabar))+diff(Ybar(X), v) = 0}

{-(diff(Y(X), zetabar))+(diff(Y(X), u))*Y(X) = 0, -(diff(Ybar(X), zeta))+(diff(Ybar(X), u))*Ybar(X) = 0, -(diff(Y(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Y(X), zeta))+(diff(Y(X), zetabar))*Ybar(X)+diff(Y(X), v) = 0, -(diff(Ybar(X), u))*Y(X)*Ybar(X)+Y(X)*(diff(Ybar(X), zeta))+Ybar(X)*(diff(Ybar(X), zetabar))+diff(Ybar(X), v) = 0}

(17)

simplify(RicciT(1, 2), shearconditions) = 0

H(X)*(diff(diff(Y(X), zeta), zetabar))*Ybar(X)-H(X)*Ybar(X)*Y(X)*(diff(diff(Ybar(X), u), zetabar))-H(X)*Ybar(X)^2*(diff(diff(Y(X), u), zetabar))-H(X)*Y(X)^2*(diff(diff(Ybar(X), u), zeta))-2*H(X)*Y(X)*Ybar(X)*(diff(diff(Y(X), u), zeta))+H(X)*Y(X)^2*Ybar(X)*(diff(diff(Ybar(X), u), u))-H(X)*Y(X)*(diff(diff(Ybar(X), u), v))+H(X)*Y(X)*Ybar(X)^2*(diff(diff(Y(X), u), u))-H(X)*(diff(diff(Y(X), u), v))*Ybar(X)+H(X)*(diff(Ybar(X), zetabar))^2+(-3*H(X)*Y(X)*(diff(Ybar(X), u))-(diff(H(X), u))*Y(X)*Ybar(X)+(diff(H(X), zeta))*Y(X)+(diff(H(X), zetabar))*Ybar(X)+diff(H(X), v))*(diff(Ybar(X), zetabar))+H(X)*(diff(Y(X), zeta))^2+(-4*H(X)*(diff(Y(X), u))*Ybar(X)-(diff(H(X), u))*Y(X)*Ybar(X)+(diff(H(X), zeta))*Y(X)+(diff(H(X), zetabar))*Ybar(X)+diff(H(X), v))*(diff(Y(X), zeta))+2*H(X)*Y(X)^2*(diff(Ybar(X), u))^2-Y(X)*((diff(H(X), zetabar))*Ybar(X)+(diff(H(X), zeta))*Y(X)+diff(H(X), v)-(diff(H(X), u))*Y(X)*Ybar(X))*(diff(Ybar(X), u))+2*(H(X)*(diff(Y(X), u))*Ybar(X)+(1/2)*(diff(H(X), u))*Y(X)*Ybar(X)-(1/2)*(diff(H(X), zeta))*Y(X)-(1/2)*(diff(H(X), zetabar))*Ybar(X)-(1/2)*(diff(H(X), v)))*(diff(Y(X), u))*Ybar(X) = 0

(18)

0 = 0

0 = 0

(19)

The values in the paraenthesis  should substitute H[4]. This sequence works in Maple 18 but not in Maple 2015

 

NULL


Download Question_algsubs_3.27.15.mw

Hi,

I'm using maple to solve non linear DE system. The error below appeared. What to do?

eqd1:={diff(u(x),x)=U(x)}:

eqd2:={diff(v(x),x)=V(x)}:

eqd3:={0.004*x*diff(U(x),x)+(x-8*x*V(x)+0.006*U(x)+(3/2-12*V(x)-8*x*diff(V(x),x))*u(x)=0}:

eqd4:=(0.008*x*(V(x)^2)+2*(0.6+x)*v(x)*V(x)+v(x)*u(x)+(v(x)^2)=0}:

fonc:={U(x),u(x),V(x),v(x)}:

sol:=dsolve(eqd1,eqd2,eqd3,eqd4,fonc}:

Error, (in PDEtools/sdsolve) too many arguments; some or all of the following are wrong: [{U(x), u(x)}, {diff(v(x), x) = V(x)}, {1/250*x*(diff(U(x), x))+(x-8*x*V(x)+3/500)*U(x)+(3/2-12*V(x)-8*x*(diff(V(x), x)))*u(x) = 0}, {1/125*x*V(x)^2+2*(3/5+x)*v(x)*V(x)+v(x)*u(x)+v(x)^2 = 0}]

 

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