Double.Type - Type Value | Power Query How

Double.Type is a type facet in the Power Query M language. It represents one of the type claims belonging to ‘type number’. It is used primarily for high-precision calculations in Power Query M. The base type of ‘type number’ in Power Query is a general numeric type, but facets like Double.Type provide additional details (such as representing double-precision floating-point numbers) for enhanced numerical accuracy in data processing.

Examples

Generally, you will face a facet when transforming column types. You can transform a column into the specified type by using Table.TransformColumnTypes:

Table.TransformColumnTypes( Source, {{ "myColumn", Double.Type }} )

Or when adding a column using Table.AddColumn:

Table.AddColumn( Source, "myColumn", 99, Double.Type" )

To inspect the kind of value you are dealing with, you can make use of the Table.Schema function. Applying it to a table returns a table with information about your columns. The Table.SingleRow function then transforms the result into a record, for easier reading.

let 
  a =  99,
   // Ascribes a type claim facet for 'type number'
  b = Value.ReplaceType( a, Double.Type ),
  // Returns a table containing a value with the ascribed "Double.Type" 
  c = #table(type table [Col1 = Value.Type( b ) ], { b } ), 
  // Shows the Table information, including typeName and value kind
  d = Table.Schema( c ),
  // For easier viewing, return table as record
  e = Table.SingleRow( d )
in 
  e

Other related facets are:

Contribute » | Contributors: Rick de Groot

Examples

Related facets