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Chapter 30
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Figure 30.1 Testing the second derivative function secDer.m. The solid black line is the input, cos(x), and the blue line is the output of the secDer function with periodic boundary conditions. This matches exactly with the analytic solution to the second derivative, -cos(x), shown as the dotted black line.
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Figure 30.2 Voltage, v, versus time, t, output of Fitzhugh-Nagumo system of equations for one point in space found using the ode45 solver with tspan=[1 100] (black dots) and with tspan=[1:4:100] (blue dots.) 3
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Figure 30.3 Traveling Fitzhugh-Nagumo wave in one dimension for t = 1 (left), t = 5 (center), and t = 10 (right). 4
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Figure 30.4 Two-dimensional traveling wave produced by the Fitzhugh-Nagumo equations for t = 0 (left), t = 300 (center), and t = 600 (right). 5
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Figure 30.5 Spiral wave produced by the Fitzhugh-Nagumo equations for t = 500 (left), t = 1000 (center), and t = 1500 (right). 6
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