Every once in a while you discover something that is obviously useful, but for some reason, you never even considered it before. That happened to me today in the form of graph digitizing software. Basically, it lets you create a chart in reverse: it starts with an image of an existing chart, and extracts the data. Why is this useful? Well, sometimes you find a great chart and want to use it for a project, but you don’t have access to the original dataset (it’s lost in time, etc). I’ve gotten around this in the past by tracing images in vector software – but obviously, extracting the data provides more precision and flexibility.
There are several digitizing programs out there, but I like Graphclick because it works with multiple chart types and has a simple interface (though it only works on Macs). Un-Scan-It is a nice one that works on PCs and Macs (but is a bit expensive).
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