Different visualization tools use different data formats, and the structure you use varies by the story you want to tell. So the more flexible you are with the structure of your data, the more possibilities you can gain. Make use of data formatting applications, and couple that with a little bit of programming know-how, and you can get your data in any format you want to fit your specific needs.
The easy way of course is to find a programmer who can format and parse all of your data, but you’ll always be waiting on someone. This is especially evident during the early stages of any project where iteration and data exploration are key in designing a useful visualization. Honestly, if I were in a hiring position, I’d likely just get the person who knows how to work with data, over the one who needs help at the beginning of every project.
What I Learned about Formatting
When I first learned statistics in high school, the data was always provided in a nice, rectangular format. All I had to do was plug some numbers into an Excel spreadsheet or my awesome graphing calculator (which was the best way to look like you were working in class, but actually playing Tetris). That’s how it was all the way through my undergraduate education. Because I was learning about techniques and theorems for analyses, my teachers didn’t spend any time on working with raw, preprocessed data. The data always seemed to be in just the right format.
This is perfectly understandable, given time ...