(detective-work)=
#  Exercise 1: Detective work 
**(10 minutes)**

Duplicate the following plot:[^f25]

:::{figure-md} detective-work-fig
:class: align-center

<img src="detective-work.png" alt="figure out how to make this plot">

Some detective work is required to duplicate this plot.
:::

:::{admonition} Hints
:class: hint
Take {ref}`another look <plotting-function>` at the `TF1` command. If class `TF1` will generate a
one-dimensional function, what class might generate a two-dimensional
function?

If `TF1` takes a function name, formula, and x-limits in its
constructor, what arguments might a two-dimensional function class use?
Where could you check your guess?

With your first try, you probably got a contour plot, not a surface
plot. Here's another hint: you want the give the option "surf1" (with
quotes) to the `Draw` method.

If youre wondering how to figure out that "surf1" was an valid option
to give to `Draw()`: Unfortunately, this is not obvious in the current
ROOT web site or documentation. 

   - Near the top of the `TF1` description,
it states "TF1 graphics function is via the `TH1` and `TGraph`
drawing functions." 

   - If you go to the `TH1` class and look at the
`Draw()` method, it says "Histograms are drawn via the
`THistPainter` class." 

   - If you go to the `THistPainter` class, you'll
see all the available `Draw()` options.

It's a long chain of references, and I didn't expect you to figure it
out on your own. The point is to prepare you for the kind of
documentation searches you often have to do to accomplish something in
ROOT; for example, {ref}`advanced exercises` and {ref}`expert exercises` in this
tutorial. Finding the "surf1" option is trivial by comparison!
:::

[^f25]: The colors don't have to be the same, since the default colors
    change in different ROOT versions.