Plotted Data Digitizer

What is this program used for?

Available for download from this page is a tcl/tk program that provides a GUI (windowed interface) to digitize the (x,y) coordinates from an image into a file. My use for this program is to digitize points from plots of data, which I can then conveniently and accurately plot against my own data (get the rulers and inaccuracy out of this method). The accuracy will be to my pixel resolution on screen, of course. The user defines two points on the image (0,0) and (1,1) and can also define a scaling (to switch the range from 0-1), and then can place a series of (x,y) entries into a file simply with mouse clicks. The GUI is pictured below.

What do I need to run it?

The program is simply a script, which requires the tcl/tk language and libraries for interpretation. Ask your system administrator about installing it or obtain it (for free) from Sun. You'll need Tcl7.4, Tk4.0 or later (I've tested through Tcl7.6, Tk4.2 to date). It is most widely available for many flavors of UNIX but also is being ported to Windows and Mac of late - check the pages at Sun for current details.


Click here for a UNIX tarfile of the digitizing program (24k).
For the individual files (if you don't have access to UNIX tar) click here , here, and here.

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A note for galcit cluster users: I currently have tcl/tk compiled for Solaris and IRIX (karman ,godel, carnap, knudsen, blast, scram, tarski). In the first line of the file digitizer.tcl you must have the path to the interpreter (called wish). Currently these are:



Note that sometimes /home/karman/d is not mounted on all the computers. If so, contact system administration (help@kelvin) if you'd like to be able to reach the file from your computer.