Preview data

Figure x: The preview data window.

This is a tool used to graph signal values from MDF-files.

Example of usage

One of the main functions is to view signals as graphs and see their route. To do so you need to select signal(s) from the file(s) you want. You select signals to the right where you see the list of signals. That list of signals is specific for the selected file. You can change which file you want signals from in the box "file viewer" on the left. Note that the files to the left are the files you had selected when clicking "Preview data". The selected signals can then be seen in the bottom under the tab "Signal preview" where you will see a quick preview of how their graph looks. By dragging the previewed signal(s) to the "Master signal preview" in the middle you can see a more extended version of the signal graph.

Functionality

Preview modes

"Master signal preview" has 3 preview modes that you can select in the bottom left corner of the "Master signal preview" area. The pre-selected view is with one graph on the left and a map on the right where the signals' routes will be shown. You can also select so that instead of a map it will show a second plot or so it only shows one plot.

Window size

If you want to have a bigger "Master signal preview" you can press the fullscreen button on the bottom right of the Master signal preview window, or you can manually hide other areas you do not wish to see by pressing the "H" on them. To show the areas again you can press the "S".

Switching between plots

There are always two plots even though there might only be one shown. This means you can always use the button "Switch" to make the plots switch places. When there are two plots shown they switch positions but when there is only one plot shown the shown plot (the left one) will switch with the hidden plot (the right one). This can be useful when comparing signals.

Zooming

To zoom in on graphs you drag between two points(not necessarily data points) on the graf and it will zoom in between those two points.To zoom out you press "Reset zoom" for L or R depending on which plot you want to zoom out. Notice that "Zoom out (R)" is only clickable when you show two plots and that is because even if there always are two plots you can only zoom out and clear shown plots.

Map

When clicking on a point in the graph you will see where the car was for that given time value on the map. Note that this only works if such GPS data is available.

Statistical data

You can see statistics for the plots and their signal(s) at the bottom under the tab "Statistics". To the left you have a buttom for if you want to show the left or right plot. What being showed is the plots signal and x/y min/max, mean value, standard devation, total amount of data samples and shown amount of data samples for each signal. Note that the plot can only show 500 samples for each signal and therefore need to hide samples for bigger signals. The plot will always try to have an as even as possible space between the samples and if its showing a signal with 502 signals it will show 251 as it will give the smoothest and most accurate view even if its not showing as many samples as it could.

Export options

At the bottom you can also download a plot as a text file. Under the tab "Data export" you select which plot you want to download, select between which time values it should download data points, set a download description (optional) and then press "To text file" to make the file ready for download. The text file you download is supported in Excel.

Saving signals

You can save the currently selected signals by pressing the signal symbol with a plus on it located on the bottom right of the "Signal List". This allows you to reload these signals in any source as long as that source contains signals with exactly matching names.

Quick selection mode

See "new in 2.46".

New in 2.46

In 2.46 you have the option to use a separate selection mode. This selection mode is called "Quick mode", and it allows you preview the same set of signals from an array of files more easily. Here is how it works:

1. Select the files that you want to preview as usual and click "Preview data".
2. Beneath the source list you will find a checkbox that says "Quick selection mode". Click it.
3. Select a file by clicking on a file in the source list.
4. Select any number of signals in the signal list.
5. If you want to add any of the signals into the master preview, then do so by dragging and dropping the thumbnails as usual.
6. You can now swap between files by selecting any file you like from the source list. When you swap file the signals you selected previously will now be selected again in the new file.

Notice: This will only work if both files have signals with the exact same name. Any deviation in signal naming will cause the program to not be able to find the signal, thus skipping it and moving on to the next signal.

Changes made in 2.48

As of version 2.48, some changes has been made to previewing data.

New or changed features are :

• Double-click a preview plot to add it the master plot.
• No module names in the preview plot, but still kept in the master plot.
• Monitoring is limited to 20 points of data per series in the map.