This features allows the user to export desired data from a specific DATAmaestro Lake folder to any pre-existing DATAmaestro project A .dmff file is created with the desired subset of data (period, frequency, variables) stored in the DATAlake and uploaded (export) it to a specific DATAmaestro project or onto the user’s local drive.

Remark: Data from different DATAlake directories can be merged into a single export .dmff file and thus be used simultaneously for analysis in a DATAmaestro project.

To export :

1. Click Export in the main menu.
2. Select From, set date followed by hour and minutes.
3. Select To, set date followed by hour and minutes. For each time step the window changes proposing new choices.

4. Enter Interval, it defines desired data sampling frequency or data intervals, for example, a database which should have one value every hour should enter “1h” in this field. Other common period examples include:

   
   

   Range (Shortcuts)	Description
   1s	Extract data at 1 second intervals
   5m	Extract data at 5 minute intervals
   1h	Extract data at 1 hour intervals
   7d	Extract data at 7 day intervals

   
   

5. Select Method, options: Snap, Average, Interpolation, Most probable, Minimum and Maximum values.

   Method	Description	Method type
   Average	The average method calculates the weighted arithmetic mean which is based on the value and the duration of each value that spans the given period or time window. For more information on Method average please check below. The formula is:  Image Modified which expands to   Image Modified where wi are the weights (or durations) and xi are the values.  (1)  Source: Average Wikipedia  Info Use Average for numerical variables like pressures, temperatures and flows.	Forward
   Interpolation	Linear interpolation is a type of interpolation which generates new values based on an existing set of values. It is achieved geometrically by drawing a straight line between two adjacent points. If the known points are given by the coordinates (x0,y0) and (x1,y1) , the linear interpolant is a line between these points. For a value x in the interval (x0,x1), the value of y along the straight line is given from the equation of slopes (1). It is useful for continuous values. Moreover the interpolation method is only calculated if there is no recorded value at a time stamp. (1)  Source: Wikipedia - Linear Interpolation Info Use Interpolate for numerical variables like pressures, temperatures and flows.	Centered
   Longest record	Selects the single recorded value or class that has the longest duration for each Period or time window. If the same value or symbol appears twice, the durations are not accumulated. Info We often use “Longest Record” for symbolic (or numerical) variables like product names or machine states, where it doesn’t make sense to interpolate or average those variables.	Forward
   Minimum	Selects the lowest/minimum recorded value for each Period or time window. If there is no record in the time window, last value is returned.	Forward
   Maximum	Selects the highest/maximum recorded value for each Period or time window. If there is no record in the time window, last value is returned.  Info You may choose to work with “Min” or “Max” if you are searching for particular events in your data. For example, if you want to know if a valve opened (0 or 1) even once during a time window, you could use “Max”.	Forward
   Raw	Exports raw values. For each timestamp with a value for at least one tag, a row will be created at that timestamp. If no value is available for a tag at a given timestamp, the previous recorded value before that timestamp is applied.  Info Normally, for batch-series data, you would use the "Raw" method.	-
   Last	Selects the last recorded value at or before a given time. Info You may choose “Last” for a lab product quality measurement, given that the last known value for quality was this last lab measurement. You may also choose “Last” for any variables that are measured “on-change” where the last known value is true until a new value is recorded.	Backward
   First	Selects the first recorded value at or after a given time.	Forward
   Snap	The snap methods samples by taking the last stored value within each time interval. In case there are no stored values within a given interval the snap method considers the last value stored. An instantaneous value at each time interval will be extracted, no aggregation is provided.	Forward

   
   

6. To select the desired list of variables, firstly choose the Folder where the tags are stored.
7. Select Tags from the tags’ lists and click the Right arrow to add them to the list for export. To remove a tag from the export list select the Tag and click the Left Arrow.
8. Repeat steps 7 and 8 to select tags from multiple directories.
9. Select Var. Naming to choose the tag name. Options: Tag Name Only, Subpath [sub/tag], Full path [/project/sub/tag]. Examples: Gas flow, Chemicals/Gas flow or /demo/Chemicals/Gas flow.
10. Click Download, this downloads a DMFF or CSV files to the user’s local drive. 

*: very unlikely to happen 

To export a file directly to DATAmaestro Analytics:

1. Choose the DATAmaestro Folder.
2. Choose a DATAmaestro Project.
3. Click Export to DATAmaestro.
   1. Note: Pop-ups must be enabled for this website. If pop-ups are blocked, enable pop-ups and then click Export to DATAmaestro.
4. DATAmaestro Analytics will open in a new Tab/Window. Under Variables Definition, select “Retrieve” and then click “Save” to complete the export to the DATAmaestro Analytics project .  
   1. Note: For large data sets there may be a delay between clicking export and the project opening in DATAmaestro Analytics.

Export Method:

Average 

This method is only available for backward compatibility. It is only useful if a previous extraction have been done with Snap method and the same result is needed. In other cases, Last and First methods should fill the needs and are simpler. 

The table below shows how the snap exported data is selected. 

The table below shows how the average exported data is calculated.