{VERSION 5 0 "IBM INTEL NT" "5.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "" -1 256 "" 1 18 0 0 0 0 0 1 0 0 0 0 0 0 0 0 } {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 }{PSTYLE "Normal" -1 256 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 1 0 0 0 0 1 0 1 0 2 2 0 1 }} {SECT 0 {EXCHG {PARA 256 "" 0 "" {TEXT 256 52 "Animation of the Fourie r Analysis of a Triangle Wave" }}{PARA 0 "" 0 "" {TEXT -1 1 " " }} {PARA 0 "" 0 "" {TEXT -1 145 " The coefficients for the cosine compo nents of the Triangle wave are : 8/(nPi)^2, for odd n values (here i t is done with (2*n-1) for \"all n\"" }}{PARA 0 "" 0 "" {TEXT -1 85 " m=number of terms to keep - then we create a \"sequence\" of the \+ sums (myseqsum) :" }}{PARA 0 "" 0 "" {TEXT -1 68 " first ter m of the sequence is just the first fourier term" }}{PARA 0 "" 0 "" {TEXT -1 119 " second term of the sequence is the sum of the first two terms, third in sequence is sum of first three terms" }} {PARA 0 "" 0 "" {TEXT -1 71 " Thus, we can watch the final waveform \+ evolve into the Triangle Wave." }}{PARA 0 "" 0 "" {TEXT -1 135 " Als o, we could create a sequence of just the fourier terms (myseq2) - we \+ can see the amplitude of each successive term gets smaller." }}{PARA 0 "" 0 "" {TEXT -1 139 " [ Once the \"gra phs\" are created, click once on the graph to highlight it, and you wi ll see \"player controls\" " }}{PARA 0 "" 0 "" {TEXT -1 91 " \+ appear in a toolbar above - to let you run the \+ animation.]" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "restart; with(plots):" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 32 "m:=10: # Number of terms to keep" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 53 "mycoeffs := seq( (8/((2*n-1)*(2*n-1)*Pi*P i)),n=1..m);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 95 "myseq := se q( (8/((2*n-1)*(2*n-1)*Pi*Pi))*cos((2*n-1)*Pi*x/2),n=1..m): # notice \+ only odd terms" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 47 "myseqsum \+ := seq(sum(myseq[nn],nn=1..n),n=1..m):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 152 "display(seq(plot(myseqsum[i], x=-1..3,color=blue, th ickness=2),i=1..m), insequence=true, title=`Evolution of Four ier series to Triangle Wave`);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 164 "# Note: Watch the top corner .. the series will very quickl y approach the triangle function - there is no \"ringing\" of the Gibb 's Phenomena as in the Square Wave." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 80 "myseq2 := seq(myseq[n],n=1..m): # these are the indiv idual terms of the sequence" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 174 "display(seq(plot(myseq2[i], x=-1..3,color=blue, thickness=2),i=1. .m), insequence=true, title=`Individual terms of the Fourier \+ series solution to the Triangle Wave`);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}}{MARK "11" 0 }{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 } {PAGENUMBERS 0 1 2 33 1 1 }