I can plot derivatives using ForwardDiff and Plots

```
using ForwardDiff
using Plots
f(x)=x^2
df(x)=ForwardDiff.derivative(f(x), x)
plot(df)
```

but QuadGK.jl gives two answers so this method won’t work. Is there a way to plot the integral using QuadGK, or another integral package, that gives one output, like ForwardDiff?

Just extract the first output from QuadGK? EDIT: And please include reproducible code when you post questions.

Ok, how do I extract an output from QuadGK.

```
using QuadGK
f(x)=x/2
quadgx(f,1,x)
```

The same way as anything else in Julia: store the result in a variable, for example:

```
julia> f(x) = x / 2
f (generic function with 1 method)
julia> y = 10
10
julia> z = quadgk(f, 1, y)
(24.75, 0.0)
julia> z[1]
24.75
```

And use the REPL or notebook to experiment and play around.

Are you looking for something like `plot(x -> quadgk(f, 1, x)[1])`

?

That is, if you want to take advantage of the fact that the first `plot`

argument can be a function, you pass a function `x -> quadgk(f, 1, x)[1]`

that takes an `x`

and returns \int_1^x f(x')dx', using `[1]`

to get the first return value of `quadgk`

(which returns a tuple).

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Perfect, and I’ll be sure to play around with different variations @dpsanders !

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