Why is this gsub not working in R
<p>I want to replace every word beginning with Jo with the word Joburg, however this code isn't working and I don't understand why.</p>

<pre><code>gsub("^Jo\\w+","Joburg",DF[,4:9])
</code></pre>

<p>My data frame has 10 columns and i'm looking to do the replacement in columns 4 to 9, all of which are factors.</p>

<p>When I run unique() afterwards i still get the original list of distinct words starting with Jo, instead of only the word Joburg throughout.</p>