{VERSION 2 3 "SUN SPARC SOLARIS" "2.3" } {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 "Hyperlink" -1 17 "" 0 1 0 128 128 1 0 0 1 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 }{CSTYLE " " -1 256 "" 0 1 0 0 92 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 257 "" 0 1 148 0 224 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 "" 0 1 0 0 40 0 1 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 }{PSTYLE "Heading 1" 0 3 1 {CSTYLE "" -1 -1 "" 1 18 0 0 0 0 0 1 0 0 0 0 0 0 0 }1 0 0 0 6 6 0 0 0 0 0 0 -1 0 }{PSTYLE "Heading 2" 3 4 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 4 4 0 0 0 0 0 0 -1 0 }{PSTYLE " Title" 0 18 1 {CSTYLE "" -1 -1 "" 1 18 0 0 0 0 0 1 1 0 0 0 0 0 0 }3 0 0 -1 12 12 0 0 0 0 0 0 19 0 }{PSTYLE "Author" 0 19 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 0 0 -1 8 8 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 18 "" 0 "" {TEXT -1 20 "Span and Null Spaces" }} {PARA 19 "" 0 "" {TEXT -1 8 "Math 230" }}{PARA 19 "" 0 "" {TEXT -1 17 "February 17, 1998" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 76 "This is a short introduction to how Maple can be used to \+ calculate and plot " }}{PARA 0 "" 0 "" {TEXT -1 22 "spans and null spa ces." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 38 "First load the linear algebra package." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "with(linalg):" }}} {SECT 1 {PARA 3 "" 0 "" {TEXT -1 31 "Plotting a Span in 3 Dimensions" }}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 7 "A Plane" }}{EXCHG {PARA 0 "" 0 " " {TEXT -1 69 "If one has a collection of vectors Maple will give you \+ minimal subset" }}{PARA 0 "" 0 "" {TEXT -1 62 "with the same span. Co nsider the following set of vectors in " }{XPPEDIT 18 0 "R^3" "*$%\"RG \"\"$" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 70 "v1 := vector([1,2,1]);\nv2 := vector([2,-2,3]); \nv3 := vector([5,-2,7]);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 6 "Using " }{HYPERLNK 17 "augment" 2 "linalg,augment" "" }{TEXT -1 56 " one ca n make a matrix whose columns are v1, v2, and v3." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 24 "M1 := augment(v1,v2 ,v3);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 12 "The command " } {HYPERLNK 17 "colspace" 2 "linalg,colspace" "" }{TEXT -1 45 " will the n give a minimal set of vectors that" }}{PARA 0 "" 0 "" {TEXT -1 31 "s pan the span of v1,v2, and v3." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "> " 0 "" {MPLTEXT 1 0 18 "V := colspace(M1);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 68 "This has two directions in the set V. By taking all possible linear" }}{PARA 0 "" 0 "" {TEXT -1 67 "combinatio ns one can plot the span of v1, v2, and v3 parametrically" }}{PARA 0 " " 0 "" {TEXT -1 6 "using " }{HYPERLNK 17 "plot3d" 2 "plot3d" "" } {TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 64 "After selecting the plot, one can rotate it using the mou se. To" }}{PARA 0 "" 0 "" {TEXT -1 51 "redraw the plot, simply hit th e return (enter) key." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 102 "plot3d(evalm((s*V[1])+(t*V[2])),s=-2..2,t=-2..2 ,\n axes=boxed,style=patch,scaling=constrained);" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 6 "A Line" }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 64 "Here is another example where a minimal set of vectors that span" }}{PARA 0 "" 0 "" {TEXT -1 47 "the span of w1, w2, and w3 has only one vector." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 117 "w1 := vector([1,2,1]);\nw2 := vector([-2,-4,-2]);\nw 3 := vector([5,10,5]);\nM2 := augment(w1,w2,w3);\nV2 := colspace(M2); " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 70 "One uses a different plotting routine to plot a curve in 3 dimensions." }}{PARA 0 "" 0 "" {TEXT -1 6 "it is " }{HYPERLNK 17 "spacecurve" 2 "plots,spacecurve" "" }{TEXT -1 45 ". Here the line is given in parametric form." }}{PARA 0 "" 0 " " {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 123 "plots[spacecurve ]([op(convert(evalm(s*V2[1]),list)),\n s=-2..2,color=red],\n \+ axes=boxed,scaling=constrained);" }}}}}{SECT 1 {PARA 3 "" 0 "" {TEXT -1 37 "Plotting a Null Space in 3 Dimensions" }}{EXCHG {PARA 0 " " 0 "" {TEXT -1 43 "For this we will use the following matrix.\n" }} {PARA 0 "> " 0 "" {MPLTEXT 1 0 42 "A := matrix([[1,2,-1],[2,0,-1],[-1, 2,0]]);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 58 "Maple will give a mini mal set the spans the null space of " }{TEXT 256 1 "A" }{TEXT -1 11 " \+ using the " }}{PARA 0 "" 0 "" {TEXT -1 8 "command " }{HYPERLNK 17 "nul lspace" 2 "linalg,nullspace" "" }{TEXT -1 43 " . Note that every ele ment in this set is" }}{PARA 0 "" 0 "" {TEXT -1 30 "perpendicular to e very row of " }{TEXT 257 1 "A" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "V3 := nullspace(A); " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 55 "As will the span above, one c an plot this nullspace in " }{XPPEDIT 18 0 "R^3" "*$%\"RG\"\"$" } {TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 123 "plots[spacecurve]([op(convert(evalm(s*V3[1]),list)), \n s=-2..2,color=red],\n axes=boxed,scaling=constraine d);" }}}}{SECT 1 {PARA 3 "" 0 "" {TEXT -1 9 "Exercises" }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 29 "Plot the span of the rows of " }}{PARA 0 "" 0 "" {TEXT -1 7 " " }{XPPEDIT 18 0 "B = MATRIX([[1,1,1],[3,3, 3],[-1,-1,-1]])" "/%\"BG-%'MATRIXG6#7%7%\"\"\"\"\"\"\"\"\"7%\"\"$\"\"$ \"\"$7%,$\"\"\"!\"\",$\"\"\"F3,$\"\"\"F3" }{TEXT -1 1 "." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 23 "Plot the null space of " }{XPPEDIT 18 0 " B" "I\"BG6\"" }{TEXT -1 1 "." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 4 "Us e " }{HYPERLNK 17 "display" 2 "plots,display" "" }{TEXT -1 48 " to plo t the results from the two problems above" }}{PARA 0 "" 0 "" {TEXT -1 38 "together. What do you conclude about " }{XPPEDIT 18 0 "NS(B)" "-% #NSG6#%\"BG" }{TEXT -1 14 " and the span " }}{PARA 0 "" 0 "" {TEXT -1 15 "of the rows of " }{XPPEDIT 18 0 "B" "I\"BG6\"" }{TEXT -1 1 "." }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 22 "Plot the null space of" }}{PARA 0 "" 0 "" {TEXT -1 5 " " }{XPPEDIT 18 0 "C = MATRIX([[2,-1],[-4,2]]) " "/%\"CG-%'MATRIXG6#7$7$\"\"#,$\"\"\"!\"\"7$,$\"\"%F,\"\"#" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 63 "This is different from the abo ve problems since the null space " }}{PARA 0 "" 0 "" {TEXT -1 6 "is in " }{XPPEDIT 18 0 "R^2" "*$%\"RG\"\"#" }{TEXT -1 19 ". You need to us e " }{HYPERLNK 17 "plot" 2 "plot" "" }{TEXT -1 12 " instead of " } {HYPERLNK 17 "spacecurve" 2 "linalg,spacecurve" "" }{TEXT -1 11 ". Th is is " }}{PARA 0 "" 0 "" {TEXT -1 26 "problem 31 on page 177 in " } {TEXT 258 25 "Elementary Linear Algebra" }{TEXT -1 9 " by Hill." }}}}} {MARK "4" 0 }{VIEWOPTS 1 1 0 1 1 1803 }