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Analysis procedure

Every analysis type (including the VIEWING analysis types) is started with the use of the "Open datafile" button on the studyfolder toolbar and by selecting a data file to process. Each analysis may include a varying number of dialogs and processing steps before results are stored in a SQL database or result datafiles. EMEGS (Qt version) will run through all steps automatically, unless user input is required. In such cases, EMEGS (Qt version) will either prompt you for a specific input with a dialog or - if more complex user input is needed - will pause the analysis until the "Resume analysis" button on the studyfolder-toolbar is pushed.


Data import

Data import is manages by a dialog which allows you to specify which channels and which time ranges of a data file you wish to load.

Selecting signals and signal usage
Based on the channel naming settings in the study configuration and the current analysis, EMEGS may preselect the correct channel.



To add a channel name to the channel name settings right-click on the row of the channel you would like to add to the channel labels of the current analysis and select "Add [EKGR-1] to [ECG] channel list" (values in brackets are different depending on the current analysis. In the same manner, you can also remove channel labels or add and remove channel lables to/from the list of optional channels, which is a set of channels that are loaded for display (see below).




If not automatically set correctly by EMEGS, you must select the required number of channels for the current analysis (the example below is an ECG analysis and requires one ECG channel) to analyze in the usage column. You can select any number of additional channels for display, channels set to ignore will not be read. The sample rate of each signal as stored in the data file is displayed in addition to signal names to help find the right channel.

Rereferencing: Even when analyzing non-EEG-data, some recording hardware setups make it necessary to rereference a recorded channel before the analysis. To notify EMEGS (Qt version) of a necessary rereferencing step, have your channel label be followed by three dashes and then the label of reference channel.
For instance: to have the channel labelled ECG1 be rereferenced to the channel labelled ECG2 when running an ECG-analysis, add ECG1---ECG2 to your ECG-channel labels.

PLEASE NOTE: this is not the recommended way to have EEG data rereferenced. See the ERP/ERF-analysis for details on how to rereference EEG data.



Selecting the data section (not yet supported)
--- under construction ---
You can also select, wether you wish to load all available data in the file or just a subsection.
This is mostly useful for extremely large data files that cover several days or hours and cannot be analyzed entirely because of limited working memory. 

PLEASE NOTE: this is not the recommended way to extract statistics of a segment of interest - to do this rather load a file entirely, edit only the time ranges of interest and extract values for selected time ranges later using the value export tool.

When loading just a subsection, you can either select to load a certain manually entered time range, or load a predefined segment
. The predefined segment option is only available if a valid timing definition is found by EMEGS either as an existing timing file, or as a timing definition in the database.
-- under construction ---




Optional channels

(not yet supported)




Batch processing

Every analysis type can also be initiated using the "Run batch processing"-button, which is a dropdown-option of the "Open datafile"-button on the file-toolbar. If started in this way, the currently selected analysis will be run automatically for every file in the batch. This kind of processing must be configured