第三组-第十队：食饵与捕食者模型.doc

食饵与捕食者模型第三组-第十队：颜琴 谢飞平 苏林伟模型一（Voltera模型:只考虑种间的相互作用）建立M函数文件：function dy=d(t,y)dy=zeros(2,1);dy(1)=y(1)-0.1*y(1)*y(2);dy(2)=-0.5*y(2)+0.02*y(1)*y(2);matlab命令文件：t,y=ode45(d,0 15,25 2)plot(t,y(:,1),-,t,y(:,2),*)title(食饵与捕食者的Voltera模型拟合曲线);xlabel(时间)；ylabel(数量);legend(食饵,捕食者);数值解如下：txy02520.06279726.287937222.0016050950.12559427.64166432.0065362260.18839129.063883892.0149882320.25118930.557298492.0271840380.56353739.080301822.161401280.87588549.783062432.435295561.18823362.665234052.9464257881.50058177.019848613.8984395621.76264589.182449745.2382257582.02470897.953918337.5754635312.28677299.3816168811.277297462.54883690.4135655316.312996422.65384483.6028026918.589415432.75885375.4934027520.848259222.86386166.6189160622.965009452.96886957.5531900424.825675643.07387748.8543250626.335953143.17888640.8963419327.454373473.28389433.901409428.175793353.38890227.9506532628.52399883.52367921.7793464728.502617113.65845617.0070395128.069820573.79323313.3573520127.337041513.9280110.6148855226.394118034.0766348.39546111725.202329214.2252576.75918695523.928357744.3738815.53353393422.624465554.5225054.61743971121.324193654.7068273.80300123819.749656234.8911493.22290023218.24452345.0754712.80302331616.823491995.2597922.49919752415.493014085.4541312.27498641214.189135735.6484692.1223173512.985438825.8428072.02488401211.878110476.0371451.97186927710.862161446.283151.9586578889.6980703586.5291551.9991761058.6592827396.7751612.0906496697.7343190467.0211662.2335909156.9121883867.3961662.560427495.8336778367.7711663.0452280484.9383152838.1461663.7357452034.1988119698.5211664.7002838653.5921271988.8961666.0364967843.0995223339.2711667.8779907522.7062230319.64616610.415615792.40169731510.0211713.9111550123961718.690606012.04309884710.7711725.231842151.99367262911.1461734.064342382.05706469411.5211745.699828942.2957467411.874259.443264542.78929949112.2272375.646968123.77355630112.5802791.306598495.74655248112.933399.746321929.52103520612.9939199.7672866810.4246899513.0545399.217738311.4106132113.1151498.0591107512.4769189413.1757596.2679946313.6184284913.2363693.838242914.8264766313.2969890.7872705716.0879964313.3575987.1560146917.3861514513.418283.0089267418.7006575713.573870.6572322721.9774828613.729457.3124871224.8123180613.88544.5826368826.926882314.040633.7506525328.1594694214.1819626.0390877928.5367267114.3233120.0394768128.3712840714.4646715.4746602927.7952078714.6060212.082016826.9245368814.7045210.26297826.1995848114.803018.78289977725.4117088214.901517.57556443524.58257772156.58852011923.729377模型二（logistic模型: 考虑种间的相互作用和的种族之间的自身阻滞作用）建立M函数文件：function dy=g(t,y)dy=zeros(2,1);dy(1)=y(1)-0.1*y(1)*y(2)-y(1)2/120;dy(2)=-0.5*y(2)+0.02*y(1)*y(2)-y(2)2/50;matlab命令文件：t,y=ode45(g,0 20,25 2)plot(t,y(:,1),-,t,y(:,2),*)title(食饵与捕食者的logistic模型拟合曲线);xlabel(时间)；ylabel(数量);legend(食饵,捕食者);数值解如下：txy02520.084926.276812991.9953783350.169827.594068971.9951656820.254728.94946671.9994791410.339630.340229792.0084580940.708536.707822572.1061210831.077343.276785652.3149997041.446249.511973342.6630829851.81554.777458413.1864441732.08857.652037393.7094457092.360959.393790774.3607133592.633959.852812195.1371446952.906958.993350096.0166624513.179956.896977936.9572552823.452853.809999557.8875167863.725850.055675988.7325532633.998845.992336179.4248140374.256142.188285399.8914005454.513538.6361872910.167905524.770835.4855515210.263889025.028232.7883966810.203517325.285630.5421596110.020995745.542928.742530449.7515977925.800327.355464569.4272584726.057726.333150859.0735284456.381125.495836238.6166137286.704525.088932068.1741753877.02825.042275667.7670303247.351425.301807237.4044020417.704625.882074997.0636088768.057926.709460016.7872642758.411127.72265726.5769187928.764328.864046566.4302486519.185230.311745696.3336572279.60631.742717146.31824121710.026833.046329996.3758986310.447634.131126196.49454653510.916534.99803536.68237645711.385435.45439966.90365070311.854335.50032937323235.19223227.3413767412.766934.662221257.50773760913.210633.999254497.62758256313.654333.297107917.69509114714.098132.632317397.71221807814.556932.039105237.68542868315.015831.586345987.62520606515.474631.297943447.54448964215.933531.160807277.45580035916.43