Data from graphs in PDF datasheets can be easily incorporated directly into your analysis after using Dagra to digitize the image.

First, import the graph into Dagra from the datasheet. Open the datasheet in Adobe Reader then either:

1. Use Reader's Snapshot tool to select and copy the graph onto the clipboard (Tools → Select & Zoom → Snapshot Tool in Adobe Reader Version 8). Then, in Dagra, choose New from Clipboard from the File menu.
2. Use Dagra's screenshot tool to create a new document in Dagra directly from an area of the screen (choose New from Screenshot from the File menu).

Once the graph is in Dagra, line up Dagra's red axes with the axes on the graph image by dragging them into place. Setup the axis limits so Dagra knows how to map its internal coordinate system to the graph's coordinate system. You can add additional axes if your graph has a secondary x- and/or y-axis or the image contains more than one graph. Dagra's help file contains all the details.

With the graph loaded and axes configured, tracing data is quick. Simply click a point on the series and drag to set its tangent. Dagra constructs a smooth Bezier curve through the points you lay down. Just a few points are needed to trace most curves accurately. Only 5 points were set to trace the thermal resistance curve of an LM35 temperature sensor below; Dagra interpolates the rest, fitting a smooth curve to the data.

Using Dagra, the thermal resistance of National Instrument's LM35 temperature sensor in a TO-46 case has been digitized.

Dagra is not a complicated new analysis tool to learn. The likes of Matlab, MathCAD and Excel have that well covered already. To use the data, simply:

• Export the digitized values to a text file, or
• Copy them to the system clipboard, or
• Open Dagra documents directly with functions for Matlab and plugins for Excel and MathCAD

Numerical values of the LM35 Thermal sensor transferred into Excel ready for additional analysis and plotting.

Download a fully functional trial version and test Dagra on your own data now:

See example applications for digitizing with Dagra or view Dagra screenshots.