// TestOde1 is the example for the 1st order system described in the README.
func TestOde1(t *testing.T) {
// Set up blocks.
var inte = Integrate{State: 1} // Initial condition x0 = 1
var plt = plot.Plot{NumChannels: 1, Size: image.Point{256, 256}}
var neg Scale = -1
var add Add
var tee Tee
var zeros Source
// The stop block terminates the simulation and
// writes the plot to ode1.png.
var stop = Stop{
Time: 3,
Callbacks: []func(){
func() {
if err := plt.Write("ode1.png"); err != nil {
t.Fatal(err)
}
},
},
}
// Define the system.
// I'm sure there exists a better way to do this.
var system System
// Add all blocks.
system.Add(&inte) // 0
system.Add(&plt) // 1
system.Add(neg) // 2
system.Add(add) // 3
system.Add(tee) // 4
system.Add(zeros) // 5
system.Add(&stop) // 6
// Connect blocks. This is the mechanical work,
// which would better be done by a front-end.
system.Connect(0, 4, 0, 0) // inte -> tee
system.Connect(4, 1, 0, 0) // tee -> plot
system.Connect(4, 2, 1, 0) // tee -> neg
system.Connect(2, 3, 0, 1) // neg -> add
system.Connect(5, 6, 0, 0) // zeros -> stop
system.Connect(6, 3, 0, 0) // stop -> add
system.Connect(3, 0, 0, 0) // add -> inte
// Add initial condition for x.
system.AddIC(1.0, 3, 1) // send 1.0 to block "add" on input 1
if err := system.Start(); err != nil {
t.Fatal(err)
}
}
// TestOde2 is the example for the 2nd order system described in the README.
func TestOde2(t *testing.T) {
fmt.Println("test ode 2")
// Set up blocks.
var inte1 = Integrate{State: 0} // Initial condition v0 = 0
var inte2 = Integrate{State: 1} // Initial condition x0 = 1
var plt = plot.Plot{NumChannels: 1, Size: image.Point{512, 256}}
var omega2 Scale = -30
var delta Scale = -0.5
var add Add3
var tee1, tee2 Tee
var zeros Source
var stop = Stop{
Time: 5,
Callbacks: []func(){
func() {
fmt.Println("writing ode2.png")
if err := plt.Write("ode2.png"); err != nil {
t.Fatal(err)
}
},
},
}
// Define the system.
var system System
// Add all blocks.
system.Add(&inte1) // 0
system.Add(&inte2) // 1
system.Add(&plt) // 2
system.Add(omega2) // 3
system.Add(delta) // 4
system.Add(add) // 5
system.Add(tee1) // 6
system.Add(tee2) // 7
system.Add(zeros) // 8
system.Add(&stop) // 9
// Connect blocks.
system.Connect(8, 5, 0, 0) // zeros -> add
system.Connect(5, 0, 0, 0) // add -> inte1
system.Connect(0, 6, 0, 0) // inte1 -> tee1
system.Connect(6, 1, 0, 0) // tee1 -> inte2
system.Connect(1, 7, 0, 0) // inte2 -> tee2
system.Connect(7, 9, 0, 0) // tee2 -> stop
system.Connect(9, 2, 0, 0) // stop -> plot
system.Connect(6, 4, 1, 0) // tee1 -> delta
system.Connect(4, 5, 0, 1) // delta -> add
system.Connect(7, 3, 1, 0) // tee2 -> omega2
system.Connect(3, 5, 0, 2) // omega2 -> add
// Add initial condition for x and v.
system.AddIC(0, 3, 0) // send 0 to block "omega2" on input 0
system.AddIC(1, 4, 0) // send 1 to block "delta" on input 0
if err := system.Start(); err != nil {
t.Fatal(err)
}
}