Welcome to DataThief
What is DataThief III
DataThief III is a program to extract (reverse engineer) data points from a graph.
Typically, you scan a graph from a publication, load it into DataThief, and save the resulting coordinates, so you can use them in calculations or graphs that include your own data.
What is new in DataThief III?
- It is written in Java, it runs on Windows, Unix, Macos...
- It is capable of tracing any more or less continuous line, even when the line crosses itself.
- It can convert data from numeric format to any other format, for instance dates.
- It is shareware. If you use DataThief
please buy the shareware registration key from
Java has had a serious security problem with a module called Log4j
DataThief does use Java, but this specific module is not included in the DataThief code, so this security problem is not present in DataThief.
For the more curious, a full list of Java modules used in DataThief is here
Usualy downloading Datathief.jar
will work. If not, see notes below.
The MD5sum for Datathief.jar is:
Even though the aim has been to create an easy to use tool, DataThief III has many possibilities that are hard to understand without the manual. So we urge you to download it.
A nice video tutorial
Kathryn Thomson made a nice video tutorial.
Changes in DataThief III version 1.7
Fixed a nasty little bug that sometimes caused a number to have an exponent of 1 less then it should be. E.g. 1e6 was shown as 1e5.
Changes in DataThief III version 1.6
Added fine motion.
To move a point it is now possible to locate the mouse pointer over the point so the pointer will turn to a crosshair.
Now you can move the point using the arrow keys on your keyboard.
When you zoom in, the motion will be even more precise.
Changes in DataThief III version 1.5
The bug that was introduced in version 1.4 was repaired.
Changes in DataThief III version 1.4
There was another bug in the formatting of numbers. The number 1.0001 was formatted as 1.0E-4.
It is fixed in version 1.4. (Thanks to Stephen Schwarz). Regretfully the fix introduced another bug. (See version 1.5)
Changes in DataThief III version 1.3
Made it possible to enter the key using copy and paste
Changes in DataThief III version 1.2
There was a serious bug in the previous versions of DataThief.
Under certain circumstances negative numbers in scientific notation were respresented as positive (ouch)!
This has been repaired in version 1.2. (Thanks to Meritt Reynolds).
Changes in DataThief III version 1.1
It is now impossible to move point to the top or the left out of the screen.
If you have lost your reference locators, you can use the reset menu item to move all locators to their default positions.
The graphs that are used as examples in the manual are
The first example
Translators example with sunrise
There is a small problem with the sunrise example.
functions use the Locale setting of your Java installation.
In plain English: the names of the months will be used according to your (Java) system's language settings.
This means that if you follow the sunrise example in the manual, you will have to give the abbreviated month names accordingly. For example, in a German system you have to give the Ref3 x-coordinate a value of 31-dez
in stead of 31-dec
The date translator code
Out of memory
I you get an error message explaining that the program quits due to a "OutOfMemoryError", this usually means that the image you are using is too big. Try reducing the dimensions of the image.
Problem with MacOS X image load
There is one known problem which I have as yet been unable to solve: On (some versions of) MacOS X, when you load an image, it is not automatiaclly displayed. Zooming in and out, or any other way to refresh the screen will do the trick. I shall try to solve the problem, but it seems a tricky little item of what my software does with how Java is implemented for MacOS X.
Problem with Windows download
Some Windows installations offer to save the Datathief.jar file as Datathief.zip. Do not accept this; java requires the file to have the 'jar' extension.
If you have problems starting Datathief.jar, the following might help:
The jar file contains a MANIFEST. The class that contains the main method is Datathief. So a basic command would be
java -classpath Datathief.jar Datathief
Or you might try
java -jar Datathief.jar
If you want to cite DataThief you can use:
B. Tummers, DataThief III. 2006 <https://datathief.org/>