I am trying to plot a graph with dates (pandas datetime) on the x axis. However, they are plotting in numerical format instead (showing up as exponents).

Example of dates:

```
0   2014-05-01
1   2014-05-02
2   2014-05-03
3   2014-05-04
4   2014-05-05
Name: date, dtype: datetime64[ns]

```

Code for plotly:

```
trace1 = go.Scatter(x = df_iso_h.date, 
                y=del18_f_hum,
               mode = 'markers')
data = [trace1]
py.iplot(data)

```

My x-axis:
[![enter image description here](https://i.stack.imgur.com/uIgzQ.png)](https://i.stack.imgur.com/uIgzQ.png)

Not sure how to fix this??