n = 100; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 0.006048975982605 n = 1000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 6.076232396232373e-04 n = 10000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 6.078967064790568e-05 n = 100000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 6.079240612503426e-06 n = 1000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 6.0745346e-04 n = 10000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 1.2690121e-04 n = 100000; x = my_pi_up( n ); abs( x - pi6 )/pi6 ans = 1.2690121e-04 x x = 1.6447253 n = 100000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447253 0.0001269 n = 10000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447253 0.0001269 n = 8000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447253 0.0001269 n = 6000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447253 0.0001269 n = 4000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447139 0.0001339 n = 5000; x = my_pi_up( n ); [x, abs( x - pi6 )/pi6] ans = 1.6447253 0.0001269 n = 4000; xu = my_pi_up( n ); xd = my_pi_down( n ); [xu, abs( xu - pi6 )/pi6; xd, abs( xd - pi6 )/pi6] ans = 1.6447139 0.0001339 1.6446841 0.0001520 n = 5000; xu = my_pi_up( n ); xd = my_pi_down( n ); [xu, abs( xu - pi6 )/pi6; xd, abs( xd - pi6 )/pi6] ans = 1.6447253 0.0001269 1.6447340 0.0001216 n = 10000; xu = my_pi_up( n ); xd = my_pi_down( n ); [xu, abs( xu - pi6 )/pi6; xd, abs( xd - pi6 )/pi6] ans = 1.6447253 0.0001269 1.6448340 0.0000608 n = 100000; xu = my_pi_up( n ); xd = my_pi_down( n ); [xu, abs( xu - pi6 )/pi6; xd, abs( xd - pi6 )/pi6] ans = 1.6447253 0.0001269 1.6449240 0.0000061 n = 1000000; xu = my_pi_up( n ); xd = my_pi_down( n ); [xu, abs( xu - pi6 )/pi6; xd, abs( xd - pi6 )/pi6] ans = 1.6447253 0.0001269 1.6449330 0.0000007 edit sqsqrt x=2;p=1; [sqrtsq(x, p) sqsqrt(x, p)] ans = 2.000000000000000 2.000000000000000 x=2;p=2; [sqrtsq(x, p) sqsqrt(x, p)] ans = 2.000000000000000 2.000000000000000 x=1;p=10; [sqrtsq(x, p) sqsqrt(x, p)] ans = 1 1 x=1;p=20; [sqrtsq(x, p) sqsqrt(x, p)] ans = 1 1 x=pi/2;p=20; [sqrtsq(x, p) sqsqrt(x, p)] ans = Inf 1.570796326625687 x=pi/2;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-09 * Inf 0.107721994469509 x=2;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-10 * Inf 0.786792853091356 x=3;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-09 * Inf 0.141214891632065 x=.5;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.000000000000000 0.000000000075771 x=.1;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.000000000000000 0.000000000024458 x=1;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 0 0 x=1.5;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-10 * Inf 0.406317942254949 x=1.1;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-11 * Inf 0.589447682583258 x=1.00001;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-09 * 0 0.106769746714549 x=1.0001;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-10 * 0 0.597364595767515 x=1.001;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-10 * Inf 0.647822344109198 1.001^2 ans = 1.002001000000000 (1.001^2)^2 ans = 1.004006004000999 ((1.001^2)^2)^2 ans = 1.008028056070055 ((1.001^2)^2)^2^2 ans = 1.016120561824374 ((1.001^2)^2)^2^2^2 ans = 1.032500996162281 ((1.001^2)^2)^2^2^2^2 ans = 1.066058307076103 ((1.001^2)^2)^2^2^2^2^2 ans = 1.136480314085966 ((1.001^2)^2)^2^2^2^2^2^2 ans = 1.291587504304936 ((1.001^2)^2)^2^2^2^2^2^2^2 ans = 1.668198281276653 ((1.001^2)^2)^2^2^2^2^2^2^2^2 ans = 2.782885505654380 ((1.0001^2)^2)^2^2^2^2^2^2^2^2 ans = 1.107820842039957 ((1.00001^2)^2)^2^2^2^2^2^2^2^2 ans = 1.010292556489493 x=1.0001;p=20; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-10 * 0 0.597364595767515 x=1.0001;p=30; l=sqrtsq(x, p); r=sqsqrt(x, p); [abs(x-l)/abs(x) abs(x-r)/abs(x)] ans = 1.0e-07 * Inf 0.976157869554016 edit my_filter edit signal my_filter my_filter my_filter my_filter my_filter my_filter f = Column 1 0.000000000000013 Column 2 1.562712527537314 -49.726318913663746i Column 3 -0.041210800682674 + 0.655026919502409i Column 4 -0.032534286380315 + 0.344176799302718i Column 5 -0.027683397157764 + 0.219136652917031i Column 6 -0.022337921944684 + 0.141036088512919i Column 7 -0.014792004088384 + 0.077542400963851i Column 8 -0.002496161356033 + 0.011167183967095i Column 9 0.021446864741067 - 0.083530023210946i Column 10 0.088676271138289 - 0.305225727272816i Column 11 1.482386192152953 - 4.562315579325071i Column 12 -0.223647939948333 + 0.621206050864438i Column 13 -0.132303512686234 + 0.334160528546582i Column 14 -0.103449709792652 + 0.239058174364521i Column 15 -0.088892177707600 + 0.188905493376168i Column 16 -0.079776189991143 + 0.156569588565818i Column 17 -0.073240036966033 + 0.133223132671828i Column 18 -0.068069134017926 + 0.115098619833552i Column 19 -0.063650625483001 + 0.100297336890515i Column 20 -0.059632139743252 + 0.087746029018940i Column 21 -0.055786551805610 + 0.076783601310671i Column 22 -0.051950168869403 + 0.066973754146373i Column 23 -0.047990782142613 + 0.058010890344138i Column 24 -0.043788886520132 + 0.049668742128895i Column 25 -0.039224757744025 + 0.041770124460315i Column 26 -0.034167672019716 + 0.034167672019710i Column 27 -0.028464919757314 + 0.026730338875191i Column 28 -0.021928585991092 + 0.019332649113985i Column 29 -0.014317687200596 + 0.011844620952266i Column 30 -0.005312089413521 + 0.004120478918936i Column 31 0.005527801989537 - 0.004016183231799i Column 32 0.018826506256891 - 0.012794480440209i Column 33 0.035505283751954 - 0.022532338233770i Column 34 0.056984324873318 - 0.033700435785701i Column 35 0.085574266768263 - 0.047044851263833i Column 36 0.125302451695248 - 0.063844788022778i Column 37 0.183865127688773 - 0.086520361650869i Column 38 0.278021234068496 - 0.120310531346755i Column 39 0.452449321276675 - 0.179137358854963i Column 40 0.879190574358814 - 0.316528083562167i Column 41 3.433836903554857 - 1.115721243616418i Column 42 -2.597037498603043 + 0.754509141284061i Column 43 -1.075632143033382 + 0.276175394139794i Column 44 -0.730290184198702 + 0.163239196368248i Column 45 -0.580410309123517 + 0.110719187938149i Column 46 -0.498954908860839 + 0.079026693987107i Column 47 -0.449824978292295 + 0.056826109917200i Column 48 -0.418969598519236 + 0.039604287478076i Column 49 -0.399931593128983 + 0.025161563105942i Column 50 -0.389511694163072 + 0.012240898127757i Column 51 -0.386189209038676 Column 52 -0.389511694163072 - 0.012240898127757i Column 53 -0.399931593128983 - 0.025161563105942i Column 54 -0.418969598519236 - 0.039604287478076i Column 55 -0.449824978292295 - 0.056826109917200i Column 56 -0.498954908860839 - 0.079026693987107i Column 57 -0.580410309123517 - 0.110719187938149i Column 58 -0.730290184198702 - 0.163239196368248i Column 59 -1.075632143033382 - 0.276175394139794i Column 60 -2.597037498603043 - 0.754509141284061i Column 61 3.433836903554857 + 1.115721243616418i Column 62 0.879190574358814 + 0.316528083562167i Column 63 0.452449321276675 + 0.179137358854963i Column 64 0.278021234068496 + 0.120310531346755i Column 65 0.183865127688773 + 0.086520361650869i Column 66 0.125302451695248 + 0.063844788022778i Column 67 0.085574266768263 + 0.047044851263833i Column 68 0.056984324873318 + 0.033700435785701i Column 69 0.035505283751954 + 0.022532338233770i Column 70 0.018826506256891 + 0.012794480440209i Column 71 0.005527801989537 + 0.004016183231799i Column 72 -0.005312089413521 - 0.004120478918936i Column 73 -0.014317687200596 - 0.011844620952266i Column 74 -0.021928585991092 - 0.019332649113985i Column 75 -0.028464919757314 - 0.026730338875191i Column 76 -0.034167672019716 - 0.034167672019710i Column 77 -0.039224757744025 - 0.041770124460315i Column 78 -0.043788886520132 - 0.049668742128895i Column 79 -0.047990782142613 - 0.058010890344138i Column 80 -0.051950168869403 - 0.066973754146373i Column 81 -0.055786551805610 - 0.076783601310671i Column 82 -0.059632139743252 - 0.087746029018940i Column 83 -0.063650625483001 - 0.100297336890515i Column 84 -0.068069134017926 - 0.115098619833552i Column 85 -0.073240036966033 - 0.133223132671828i Column 86 -0.079776189991143 - 0.156569588565818i Column 87 -0.088892177707600 - 0.188905493376168i Column 88 -0.103449709792652 - 0.239058174364521i Column 89 -0.132303512686234 - 0.334160528546582i Column 90 -0.223647939948333 - 0.621206050864438i Column 91 1.482386192152953 + 4.562315579325071i Column 92 0.088676271138289 + 0.305225727272816i Column 93 0.021446864741067 + 0.083530023210946i Column 94 -0.002496161356033 - 0.011167183967095i Column 95 -0.014792004088384 - 0.077542400963851i Column 96 -0.022337921944684 - 0.141036088512919i Column 97 -0.027683397157764 - 0.219136652917031i Column 98 -0.032534286380315 - 0.344176799302718i Column 99 -0.041210800682674 - 0.655026919502409i Column 100 1.562712527537314 +49.726318913663746i my_filter f = Column 1 0.000000000000013 Column 2 1.562712527537314 -49.726318913663746i Column 3 -0.041210800682674 + 0.655026919502409i Column 4 -0.032534286380315 + 0.344176799302718i Column 5 -0.027683397157764 + 0.219136652917031i Column 6 -0.022337921944684 + 0.141036088512919i Column 7 -0.014792004088384 + 0.077542400963851i Column 8 -0.002496161356033 + 0.011167183967095i Column 9 0.021446864741067 - 0.083530023210946i Column 10 0.088676271138289 - 0.305225727272816i Column 11 1.482386192152953 - 4.562315579325071i Column 12 -0.223647939948333 + 0.621206050864438i Column 13 -0.132303512686234 + 0.334160528546582i Column 14 -0.103449709792652 + 0.239058174364521i Column 15 -0.088892177707600 + 0.188905493376168i Column 16 -0.079776189991143 + 0.156569588565818i Column 17 -0.073240036966033 + 0.133223132671828i Column 18 -0.068069134017926 + 0.115098619833552i Column 19 -0.063650625483001 + 0.100297336890515i Column 20 -0.059632139743252 + 0.087746029018940i Column 21 -0.055786551805610 + 0.076783601310671i Column 22 -0.051950168869403 + 0.066973754146373i Column 23 -0.047990782142613 + 0.058010890344138i Column 24 -0.043788886520132 + 0.049668742128895i Column 25 -0.039224757744025 + 0.041770124460315i Column 26 -0.034167672019716 + 0.034167672019710i Column 27 -0.028464919757314 + 0.026730338875191i Column 28 -0.021928585991092 + 0.019332649113985i Column 29 -0.014317687200596 + 0.011844620952266i Column 30 -0.005312089413521 + 0.004120478918936i Column 31 0.005527801989537 - 0.004016183231799i Column 32 0.018826506256891 - 0.012794480440209i Column 33 0.035505283751954 - 0.022532338233770i Column 34 0.056984324873318 - 0.033700435785701i Column 35 0.085574266768263 - 0.047044851263833i Column 36 0.125302451695248 - 0.063844788022778i Column 37 0.183865127688773 - 0.086520361650869i Column 38 0.278021234068496 - 0.120310531346755i Column 39 0.452449321276675 - 0.179137358854963i Column 40 0.879190574358814 - 0.316528083562167i Column 41 3.433836903554857 - 1.115721243616418i Column 42 -2.597037498603043 + 0.754509141284061i Column 43 -1.075632143033382 + 0.276175394139794i Column 44 -0.730290184198702 + 0.163239196368248i Column 45 -0.580410309123517 + 0.110719187938149i Column 46 -0.498954908860839 + 0.079026693987107i Column 47 -0.449824978292295 + 0.056826109917200i Column 48 -0.418969598519236 + 0.039604287478076i Column 49 -0.399931593128983 + 0.025161563105942i Column 50 -0.389511694163072 + 0.012240898127757i Column 51 -0.386189209038676 Column 52 -0.389511694163072 - 0.012240898127757i Column 53 -0.399931593128983 - 0.025161563105942i Column 54 -0.418969598519236 - 0.039604287478076i Column 55 -0.449824978292295 - 0.056826109917200i Column 56 -0.498954908860839 - 0.079026693987107i Column 57 -0.580410309123517 - 0.110719187938149i Column 58 -0.730290184198702 - 0.163239196368248i Column 59 -1.075632143033382 - 0.276175394139794i Column 60 -2.597037498603043 - 0.754509141284061i Column 61 3.433836903554857 + 1.115721243616418i Column 62 0.879190574358814 + 0.316528083562167i Column 63 0.452449321276675 + 0.179137358854963i Column 64 0.278021234068496 + 0.120310531346755i Column 65 0.183865127688773 + 0.086520361650869i Column 66 0.125302451695248 + 0.063844788022778i Column 67 0.085574266768263 + 0.047044851263833i Column 68 0.056984324873318 + 0.033700435785701i Column 69 0.035505283751954 + 0.022532338233770i Column 70 0.018826506256891 + 0.012794480440209i Column 71 0.005527801989537 + 0.004016183231799i Column 72 -0.005312089413521 - 0.004120478918936i Column 73 -0.014317687200596 - 0.011844620952266i Column 74 -0.021928585991092 - 0.019332649113985i Column 75 -0.028464919757314 - 0.026730338875191i Column 76 -0.034167672019716 - 0.034167672019710i Column 77 -0.039224757744025 - 0.041770124460315i Column 78 -0.043788886520132 - 0.049668742128895i Column 79 -0.047990782142613 - 0.058010890344138i Column 80 -0.051950168869403 - 0.066973754146373i Column 81 -0.055786551805610 - 0.076783601310671i Column 82 -0.059632139743252 - 0.087746029018940i Column 83 -0.063650625483001 - 0.100297336890515i Column 84 -0.068069134017926 - 0.115098619833552i Column 85 -0.073240036966033 - 0.133223132671828i Column 86 -0.079776189991143 - 0.156569588565818i Column 87 -0.088892177707600 - 0.188905493376168i Column 88 -0.103449709792652 - 0.239058174364521i Column 89 -0.132303512686234 - 0.334160528546582i Column 90 -0.223647939948333 - 0.621206050864438i Column 91 1.482386192152953 + 4.562315579325071i Column 92 0.088676271138289 + 0.305225727272816i Column 93 0.021446864741067 + 0.083530023210946i Column 94 -0.002496161356033 - 0.011167183967095i Column 95 -0.014792004088384 - 0.077542400963851i Column 96 -0.022337921944684 - 0.141036088512919i Column 97 -0.027683397157764 - 0.219136652917031i Column 98 -0.032534286380315 - 0.344176799302718i Column 99 -0.041210800682674 - 0.655026919502409i Column 100 1.562712527537314 +49.726318913663746i my_filter my_filter my_filter my_filter my_filter my_filter my_filter my_filter my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 28 my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 28 my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 31 my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 31 my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 31 my_filter {Warning: Imaginary parts of complex X and/or Y arguments ignored} > In my_filter at 31 edit my_LU my_LU( .1 ) ans = 1 0 10 1 [L, U] = my_LU( .1 ) L = 1 0 10 1 U = 0.100000000000000 -1.000000000000000 0 11.000000000000000 eps = .01; A = [ eps -1; 1 1]; [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) ans = 0 eps = .00001; A = [ eps -1; 1 1]; [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) ans = 6.861567364029007e-17 eps = .000000001; A = [ eps -1; 1 1]; [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) ans = 6.861555644282676e-17 eps = 10^-7; A = [ eps -1; 1 1]; [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) ans = 7.2224054e-16 [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) L = 1 0 10000000 1 U = 1.0e+07 * 0.0000000 -0.0000001 0 1.0000001 ans = 7.2224054e-16 format long [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) L = 1 0 10000000 1 U = 1.0e+07 * 0.0000000 -0.0000001 0 1.0000001 ans = 7.2224054e-16 eps = 10^-8; A = [ eps -1; 1 1]; [L, U] = my_LU( eps ); norm( L*U - A )/norm( A ) ans = 0.6180340 L*A ans = 1.0e+07 * 0.000000000000001 -0.000000100000000 0.000000200000000 -9.999999900000001