if( !require('phaseR') ){ install.packages('phaseR') } library(phaseR) A = matrix(c(2, -5/2, 9/5, -1), nrow=2, ncol=2, byrow=T) print(eigen(A)) my_yprime = function(t, y, parameters){ dy = parameters$A %*% y list(dy) } diff_eq_params = list(A=A) #postscript("../../WriteUp/Graphics/Chapter7/chap_7_sect_6_prob_4_plot.eps", onefile=FALSE, horizontal=FALSE) flowField(my_yprime, x.lim=c(-40, 40), y.lim=c(-40, 40), parameters = diff_eq_params, points=21, add=FALSE, main='Problem 4') trajectory(my_yprime, y0 = c(3, 8), t.end = 3.0, parameters = diff_eq_params, col='black') trajectory(my_yprime, y0 = c(-2.5, -5), t.end = 3.0, parameters = diff_eq_params, col='black') trajectory(my_yprime, y0 = c(2, -2), t.end = 3.0, parameters = diff_eq_params, col='black') trajectory(my_yprime, y0 = c(-2, 2), t.end = 3.0, parameters = diff_eq_params, col='black') grid() #dev.off()