{VERSION 6 0 "IBM INTEL NT" "6.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }} {SECT 0 {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 218 "# drumhead problem, General case, Example 2 in Asmar 4.3\n# u_\{tt\} = c^2(laplacian u), \+ u=0 on clamped edge\n# circle radius=a, c=wave speed, \n# position = f (r,theta) = (a^2-r^2)*r*sin(theta), \n# velocity = g(r,theta) = 0" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 52 "a:=1;c:=1;N:=5;f:=(r,theta)- >(a^2-r^2)*r*sin(theta);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 38 "alpha1:=evalf([BesselJZeros(1,1..N)]);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 54 "b1:=n->2*2*(a^5)*4/(alpha1[n]^3*BesselJ(2,alpha1[n])) ;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 87 "u:=(r,theta,t)->sin(th eta)*sum(b1(n)*BesselJ(1,alpha1[n]*r)*cos(alpha1[n]*c*t),n=1..N);" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 67 "addcoords(z_cylindrical,[z,r ,theta],[r*cos(theta),r*sin(theta),z]);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 81 "plot3d(f(r,theta),r=0..a,theta=0..2*Pi,coords=z_cylin drical,orientation=[13,81]);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 64 "#plot3d(u(r,theta,0),r=0..a,theta=0..2*Pi,coords=z_cylindrical); " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 110 "plots[animate](plot3d, \n[u(r,theta,t),r=0..a,theta=0..2*Pi,coords=z_cylindrical,orientation= [13,81]],t=0..3.1);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "# b1 can also be defined by integration directly." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 150 "b2:=n->(2/(Pi*BesselJ(2,alpha1[n])^2))*\nint(in t(f(r,theta)*BesselJ(1,alpha1[n]*r)*r*sin(theta),theta=0..2*Pi),r=0..a );\nseq(evalf(b2(j)-b1(j)),j=1..N);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}}{MARK "12" 0 }{VIEWOPTS 1 1 0 3 2 1804 1 1 1 1 } {PAGENUMBERS 0 1 2 33 1 1 }