# Mathematica Plotting the solution of an ODE

1. Feb 12, 2019 at 6:01 AM

### Robin04

I'm trying to plot the solution to an ODE (with given initial values) but there are some constants in it that I want to evaluate with sliders and I'm not sure what is the right syntax for this.

Code (Text):
Manipulate[Plot[solution1[t], {t, 0, 10}, PlotRange -> {-Pi, Pi}],
{{a, 1, "Driving amplitude"}, 0, 10, Appearance -> "Labeled"},
{{g, 9.81, "Gravitational acceleration"}, 0, 10,
Appearance -> "Labeled"},
{{l, 1, "Length"}, 0, 10, Appearance -> "Labeled"},
{{\[Gamma], 1, "Driving frequency"}, 0, 10, Appearance -> "Labeled"}]

If I copy solution1 explicitly into plot it works, but if I refer to it by the variable name it doesn't. What's the correct syntax for this?

2. Feb 12, 2019 at 6:32 AM

### Staff: Mentor

3. Feb 12, 2019 at 6:32 AM

### Staff: Mentor

I have found the same problem with Manipulate. I have not found a way around it.

4. Feb 13, 2019 at 2:38 PM

### Bill Simpson

I have had consistent success with putting all the needed definitions and functions inside the Manipulate

Manipulate[
sol=p[t]/.DSolve[{a p''[t]==p[t],p[0]==0,p'[0]==a},p[t],t][[1]];
Plot[sol,{t,0,4}],
{{a,1},0,4}
]