README.md

Transposing Data from an Aircraft

Overview

This example processes information about the pitch, yaw, roll, and velocity of an aircraft in flight. This example conceptualizes an event as a row that consists of multiple columns. A Transpose window is used to interchange an event’s rows as columns, and columns as rows. The attributes of the Transpose window govern the rearrangement of data.

As the Transpose window has two modes, long and wide, this example consists of two parts:

• The esp-studio-examples/Advanced/transpose_wide/ directory contains the resources for wide mode
• The esp-studio-examples/Advanced/transpose_long/ directory contains the resources for long mode

In the following instructions wide mode first is discussed first.

For more information about how to install and use example projects, see Using the Examples.

Source Data for Wide Mode

The input-wide.csv file contains event streams from the aircraft in flight.

The seventeen events in the file contain data about four planes: turboprop #1, turboprop #2, jet #1, and jet #2. Each event contains either a pitch, velocity, roll, or yaw value at a specific time, as well as the plane's latitude and longitude. It is not easy to find all the information for a specific plane, because information relating to each plane is located on several rows.

Workflow for Wide Mode

The following figure shows the diagram of the project:

• The SourceW window is a Source window. This is where aircraft events from the input-wide.csv file enter the model.
• The TransposeW is a Transpose Window. This is where the transposition of the aircraft events occurs. The attributes of the Transpose window govern the rearrangement of data.

SourceW

Explore the settings for the SourceW window:

1. Open the project in SAS Event Stream Processing Studio and select the SourceW window.
2. In the right pane, expand State and Event Type. Observe the following settings:
   • The Window state and index field is set to Stateless (pi_EMPTY). This index does not store events.
   • The Accept only “Insert” events check box is selected. This causes the Source window to reject any events with an opcode other than Insert.
3. To examine the window's output schema, on the right toolbar, click . Observe the following fields:
   • ID: This field is the event's ID, which is also selected as the key field.
   • PlaneID: This field identifies which aircraft provides the data.
   • TAG: This field specifies whether the data contains the aircraft’s pitch, yaw, roll, or velocity.
   • value: This field records the numerical value for pitch, yaw, roll, or velocity.
   • time: This field captures when the pitch, yaw, roll, or velocity is recorded.
   • lat: This field captures the plane's latitude.
   • long: This field captures the plane's longitude.
4. Click .

TransposeW

Explore the settings for the TransposeW window:

1. Select the TransposeW window.
2. In the right pane, expand Settings. Observe the following details:
   • Wide mode is selected. Wide mode produces one event per incoming event.
   • The Tag name field is set to TAG, which is a field from the SourceW window's output schema.
   • The Included tags field specifies the pitch, yaw, roll, or velocity fields.
   • The Tag values field specifies that the value and time fields, from the SourceW window's output schema, provide the numerical values for the included tags.
   • The Group by field that the PlaneID field is to be used to group the data that the TransposeW rearranges.
3. To examine the window's output schema, on the right toolbar, click . Observe the following details:
   • The ID, PlaneID, lat, and long fields come from the SourceW window.
   • The other fields, such as pitch_value and pitch_time, contain the numerical value of pitch, yaw, roll, or velocity, or the time at which that data was recorded.
4. Click .

Test the Project and View the Results for Wide Mode

If you do not use the Install example button in SAS Event Stream Processing Studio, note that if you use the Publish button to publish events from the input-wide.csv file into the SourceW window, you must specify the following date format: %Y-%m-%d %H:%M:%S. For more information, see Publish Events from a CSV file.

When you test the project, the results for each window appear on separate tabs. The following figure shows the results for the SourceW tab. This tab displays the events received from the aircraft. Information relating to each plane is located on several rows. For example, the pitch for turboprop #1 is on the first row but the yaw for the same plane is on the tenth row.

The following figure shows the results for the TransposeW tab, with the rearranged data. All the information for turboprop #1 is on the first row. Observe the following points:

• Wide mode produces output events that contain multiple columns, each based on the input events.
• The Included tags field was used to specify which specific values of TAG are to be included in the output events. As a result, all four values of TAG are included: pitch, yaw, roll, and velocity. Output columns are formed by taking the cross product of the following: {pitch, yaw, roll, velocity} times {value, time}. This yields pitch_value, pitch_time, yaw_value, yaw_time, and so on as column names.
• Output events are grouped by the value of PlaneID.

Next Steps: Long Mode

When you use long mode, you obtain the inverse results of wide mode. The Transpose window produces a number of events for each wide event that it receives. Input schema for the Source window must reflect combinations of fields.

Use the resources in the esp-studio-examples/Advanced/transpose_long/ directory:

1. Observe that the input-long.csv file contains only one event. The event contains information for just one plane The value and time associated with pitch, yaw, roll, and velocity are included in this event. Latitude and longitude are included too.
2. Open the project, and view the output schema and settings for the SourceW and TransposeL windows.
3. Test the example. If you use the Publish button to publish events from the input-long.csv file into the SourceW window, you must specify the following date format: %Y-%m-%d %H:%M:%S.

The following figure shows the results for the SourceW tab.

The following figure shows the results for the TransposeL tab, with the rearranged data.

Additional Resources

For more information, see SAS Help Center: Using Transpose Windows.