Using DifferentialEquations with treatment of uncertainties

General Usage
1

I try to reproduce the code found on the site:
The accelerating adoption of Julia

The first part of the code is reproduced without problem. Loading the Plots package, not mentioned in the article.

But in the part of the treatment of uncertainties I present the following problem:
ERROR: UndefVarError: ± not defined
What package should I include in order for the code run successfully?

#https://lwn.net/Articles/834571/
using DifferentialEquations
using Plots
r(f,p,t) = f - f^2
tint = (0.0, 8.0)
r0 = 0.05
prob = ODEProblem(r, r0, tint)
sol = solve(prob)
plot(sol.t, sol.u, key=false)
#Suppose there was some uncertainty attached to our knowledge of the initial condition in the above problem
Julia>r0m = 0.05 ± 0.01
ERROR: UndefVarError: ± not defined
Stacktrace:
 [1] top-level scope at REPL[10]:1
rm(f,p,t) = (1 ± 0.0)*(f - f^2)
tintm = (0.0*1 ± 0, 8.0*1 ± 0)
probm = ODEProblem(rm,r0m,tintm)
solm = solve(probm)
plot(solm.t, solm.u, key=false)
2

Did you do using Measurements?

1 Like
3

My apologies, As I read the article more carefully, I found where it is mentioned:

We will want to use the packages Plots and Measurements in our demonstration as well, so we install them and repeat the using commands on them.

I pay more attention in future reading before reaching the Forum

1 Like
4

No probs! Arguably, the article should provide working code samples.