In the old days, if someone had a scientific graph, then readers would only have access to the rastered image. So if you wanted to get the raw data from the plot, you could use something like DataThief or Webplotdigitizer on a rastered image like the one below.
These days, scientific publications usually require authors to submit plots in vector format (pdf or eps). Which means you can directly open up the plot in illustrator and see the data being plotted (usually as some path object?). For example, Figure 5a from here is a vector plot that is accessible from the pdf (reproduced below).
My questions are the following:
- What are the usual object types for a line in an XY plot (see Figure 5a in the above pdf)?
- What is the best way to run a script over the object (in Illustrator or some other program) to get the exact position of the points of the line?
Edit: I already saw this question, but rather than just getting a single point associated with the object, I wanted to absolute position of all the sub-points (if that makes sense). That way I can recreate the graph using the positions of the axes labels.