Agree with the idea in general and with @parvelous as to why not 2 decimal places. But given you stressed on "full upvotes to one decimal place" makes me wonder ... could it be a pie chart instead of the decimal showing how much of the votes were full vs part-voting?
This feature for sure would help noobs be able to see how the upvotes towards their posts are affecting earnings from the beginning as well as to the value that people are placing on the posts.