Media 6 Degrees (chapter 5) data does not match code

[SJBertram]

The R code for the Media 6 Degrees exercise in chapter 5 starts with the following:

set <- read.table(file, header = TRUE, sep = "\t", row.names = "client_id")

The sample data contains no column called "client_id". This results in a crash from the following:

Error in data[[rowvar]] : 
  attempt to select less than one element in get1index
Calls: read.table

[SJBertram]

The code-based solution is to replace:
set <- read.table(file, header = TRUE, sep = "\t", row.names = "client_id")
with:
set <- read.table(file, header = TRUE, sep = "\t")
R will then number the rows instead.