## Time for action – plotting a polynomial function

To illustrate how plotting works, let's display some polynomial graphs. We will use the NumPy polynomial function `poly1d()` to create a polynomial.

1. Take the standard input values as polynomial coefficients. Use the NumPy `poly1d()` function to create a polynomial:

`func = np.poly1d(np.array([1, 2, 3, 4]).astype(float))`
2. Create the `x` values with the NumPy the `linspace()` function. Use the range `-10` to `10` and create `30` even spaced values:

`x = np.linspace(-10, 10, 30)`
3. Calculate the polynomial values using the polynomial we created in the first step:

`y = func(x)`
4. Call the `plot()` function; this does not immediately display the graph:

`plt.plot(x, y)`
5. Add a label to the `x` axis with the `xlabel()` function:

`plt.xlabel('x')`
6. Add a label to the `y` axis with the `ylabel()` function:

`plt.ylabel('y(x)')`
7. Call the `show()` function to display the graph:

`plt.show()`

The following is a plot with polynomial coefficients 1, 2, 3, and 4:

### What just happened?

We displayed a polynomial graph...