{VERSION 3 0 "IBM INTEL NT" "3.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 }{CSTYLE "2D Comment" 2 18 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 } {PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 0 "" 0 "" {TEXT -1 127 "Here are the three equati ons that (parametrically) generate the umbilic torus that appears on t he cover of our Cal I text book:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 45 "z := sin(u)*((7.+cos(u/3-2*v)+2*cos(u/3+v)));" } {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 45 "y := cos(u) *((7.+cos(u/3-2*v)+2*cos(u/3+v)));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "x := sin(u/3-2*v) + 2.*sin(u/3+v);" }{TEXT -1 0 "" }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 81 "for i to 12 do p.i:=plot3d( [x,y,z],u=-Pi..Pi,v=-Pi..Pi,orientation=[30*i,90]) od:" }{TEXT -1 0 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 51 "plots[display]([seq(p.i ,i=1..12)],insequence=true);" }{TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 " " {TEXT -1 90 "You could do it this way: multiply your parametric expr essions by the 3x3 rotation matrix " }{XPPEDIT 18 0 "matrix([[cos(k), \+ sin(k), 0], [-sin(k), cos(k), 0], [0, 0, 1]]);" "6#-%'matrixG6#7%7%-%$ cosG6#%\"kG-%$sinG6#F+\"\"!7%,$-F-6#F+!\"\"-F)6#F+F/7%F/F/\"\"\"" } {TEXT -1 2 ". " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 89 "plots[ani mate3d]([cos(k)*x+sin(k)*y,-sin(k)*x+cos(k)*y,z],u=-Pi..Pi,v=-Pi..Pi,k =-Pi..Pi);" }{TEXT -1 0 "" }}}}{MARK "0 0 0" 127 }{VIEWOPTS 1 1 0 1 1 1803 }