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// Example visualization of Hooke's law.
//
// Copyright (C) 2020 Juan Marín Noguera
//
// This file is part of Solvned.
//
// Solvned is free software: you can redistribute it and/or modify it under the
// terms of the GNU Lesser General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option) any
// later version.
//
// Solvned is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
// A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
// details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with Solvned. If not, see <https://www.gnu.org/licenses/>.
package main
import (
"fmt"
"github.com/Arafatk/glot"
"mned"
"mned/ivp"
"mned/method"
)
func spring1(speed float64) {
spring := ivp.HookeSpring{
Mass: 1,
Spring: 1.5,
Length: 0.7,
Friction: 0.3,
Amplitude: 0.4,
AngleSpeed: speed,
}
problem := spring.ToIVP()
plot, err := glot.NewPlot(2, true, false)
if err != nil {
fmt.Printf("Creating the plot: %v\n", err)
return
}
if err := plot.SetXLabel(
fmt.Sprintf("Time (s) -- w = %v", speed),
); err != nil {
fmt.Printf("Drawing the X label: %v\n", err)
return
}
solution, _ := mned.DenseSolve(
method.RKFehlberg(0.0001, 0.01, 1e-7, 0.5),
&problem,
0,
40,
mned.HermiteForIVP(&problem),
)
coord := solution.PointCoords()
if err := plot.AddPointGroup("Position (m)", "lines", [][]float64{
coord[0], coord[1],
}); err != nil {
fmt.Printf("Drawing the position: %v\n", err)
}
if err := plot.AddPointGroup("Velocity (m/s)", "lines", [][]float64{
coord[0], coord[2],
}); err != nil {
fmt.Printf("Drawing the velocity: %v\n", err)
}
}
func main() {
spring1(0)
spring1(1.3)
spring1(2.4)
spring1(3.5)
}
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