for finding a,b,c the most compatible with the model

Is this for a class? We cannot help you with homework questions on this forum.

nope i just wanna use julia but i donβt know how

Okay.

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ββ'julia

using DifferentialEquations

using Pkg

#using Plots

using Plots

function f(du, u, h, p, t)

```
a, b,c, Ο = p
β = h(p, t - Ο, idxs = 1)
du[1] = u[1] * (1 - u[1] - (a * β + b)*exp(-c*β))
```

end

u0 = [0.008]

Ο = 7

h(p, t; idxs = 1) = 0.008

a = 0.517;

b = 0.988;

c=0.173;

p = [a, b,c,Ο]

tspan = (8.0, 23.0)

prob = DDEProblem(f, u0, h, tspan, p, canstant_lag = [Ο])

sol = solve(prob,saveat=1)

temps=[8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23]

verus=[5.011,0.199,0.01,0.0063,1.0056,0.008,0.0056,0.003,0.005,0.01,0.016,0.02,0.039,0.015,0.0001,0.0001]

L=[temps,verus]

scatter!(temps,verus)

vir=Array(L)

temp_prob=remake(prob,p=[10,5,40,6])

temp_sol=solve(temp_prob,saveat=1)

using DiffEqFlux,Optim

function loss(p)

temp_prob=remake(prob,p=p)

temp_sol=solve(temp_prob,saveat=1)

c=sum(abs2,Array(temp_sol)-vir)

end

loss([1,2,4,5])

pinit=[1,2,3,4]

res=DiffEqFlux.sciml_train(loss,pinit,BFGS())

βββ

I wanna transform vir to the same dimension of temp_sol

**Post** **quoted code** by enclosing code blocks in triple-backticks :

```
```julia
function f(x, y)
x + y
end
```
```

This will highlight syntax and use a monospace font.

Just transpose it and set `saveat`

to the right time points? (saveat = 16:23 if Iβm not mistaken?)