XLS File Reader

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Summary: This process reads point data from a Microsoft Excel (.XLS) file.

Input:

  • XLS Path (1 Path) The path to the Microsoft Excel (.XLS) source file containing the data.

Output: Feature Collection , Feature

  • Description: The set of data points corresponding to the rows of the spreadsheet.

Attributes:

  • Sheet The Excel sheet to read data from. The attribute can either be defined by the zero-based numeric offset of the sheet within the workbook, or by the name specified in the workbook. If no value is specified for the attribute (the default behaviour) the first sheet (0th) is chosen.
  • Resolution The PYXIS resolution to use as the default when viewing the data.
  • Label Row The row in the spreadsheet that will be used to name the fields being imported.
  • Latitude Column The speadsheet column that contains latitude information.
  • Longitude Column The speadsheet column that contains longitude information.
  • Data Column Start The first column of data to read from the spreadsheet. This is a 0-based value.
  • Data Column End The last column of data to read from the spreadsheet. This is a 0-based value.
  • Data Row Start The first row of data to read from the spreadsheet. This is a 0-based value.
  • Data Row End The last row of data to read from the spreadsheet. This is a 0-based value.

Details

You will not typically use this process directly, but will instead use the XLS Import wizard which automatically creates a pipeline including this process and populates the attributes of the process for you. The pipeline includes the following processes:

  • a Data File process which specifies the name and location of the source .XLS file
  • an XLS File Reader process
  • an Apply Style process which specifies the icon you want to use to represent the data points from the spreadsheet

The .XLS file is subject to the following conditions:

  • The file must have a contiguous data block.
  • Each row represents one point data feature.
  • Each column must be of uniform type (Integer, Float, or String).
  • Formula results are not processed, only raw data values.
  • Data values of unknown type are ignored.
  • Coordinates are specified in decimal degrees according to the WGS84 datum.
  • Empty cells within the data block are treated as 0.0 (Double) or "" (String), not as NULL.

The default attribute values represent a table that is the full size of the sheet (no blank formatting columns surrounding the table). The first row of the table is the field names, with the first and second column being lat and lon. If you pointed to an .XLS file in this format using the default settings, the pipeline would initialize and show data.

The area of the spreadsheet containing the data is defined by four attributes: Data Column Start, Data Column End, Data Row Start, and Data Row End. These are 0-based identifiers (so for example if the data begins in the first column enter a 0 for the Data Column Start attribute). For the end attributes (Data Column End, and Data Row End), you can specify a value of -1 to indicate that the end of the area is limited by the size of the sheet rather than a particular row or column in the sheet. A possible advantage of specifying the end of the data using a -1 value is that if you add new rows or columns to the source .XLS file, the process will automatically include the new rows and columns.

The Resolution attribute indicates the default resolution for the data source, and the one that will be used if you choose the 'Go To' option when viewing the associated pipeline from the Library. When you use the XLS Import wizard, WorldView sets the default value for the Resolution attribute to 20. If you want you can change this value to something more appropriate. For example, if the data points in the spreadsheet represent cities you might choose a resolution of 15. If the data points represented something smaller and closer together, such as ant hill locations, you might choose a resolution of 35.

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