javascript - D3 Bar Graph example not working locally

I am very new to D3, and wanted to see how an example would work locally. I copied and pasted the bar graph code to a local file called index.html, and also copied over the data.tsv. For some reason, absolutely nothing is showing up when I open the file on a browser! I tried changing the script src to "d3/d3.v3.min.js" because that is the folder the d3 I downloaded is in. However, this does not work either. For every example I have tried I have yet to successfully view a D3 example. Help would be appreciated!

The index.html code is as follows:

and the data.tsv is in the following format:
letter frequency
A .08167

B .01492
C .02780
D .04253
E .12702
F .02288
G .02022
H .06094
I .06973