extend.range

extend.range(T.n : number) 🡒 U.*, table function

Creates multiple lines for each line of the original table. The resulting table U is an extension of the original table T. The values T.n must be positive integers or the function fails.

In a typical use case, the function creates a “scenario” line for each line/item in a (catalog) table so that you can do computations on each scenario. For example, imagine you have one line for each pair of shoes in your catalog in a table, and you now want to analyze three different scenarios for each pair of shoes; the function will then create three lines instead of one for each pair of shoes in the table U, one line for each scenario.

Formal definition

table U = extend.range(T.Count)

This expects that T.Count is a number, and will produce a new table U and that contains all primary dimensions of T as secondary dimensions (meaning that the lines of T and U are associated in a way that one can broadcast from T into U and aggregate from U into T). The lines in the new table are such that T.Count == count(U.*) (meaning: the number of lines of U associated with a line of T is equal to the value of T.Count on that line).

The output table contains a numbering column named U.N, such that for each line of T, the associated lines of U are numbered from 1 to T.Count inclusive.

As all extend functions, extend.range() will only copy the column of the table’s primary dimension to the new table - no other columns will be copied.

Example 1

table T = with
  [| as A |]
  [| 1 |]
  [| 1 |]
  [| 3 |]

table U = extend.range(T.A)

show table "" a1c6 with
  T.A
  U.N

Expected output of example 1

Note that in this example, the table T does not have a named primary dimension. Even though its primary dimension is copied to U, it cannot be accessed by name. Columns in general are not being copied: The T.A column will not be copied to the new table U; the only column in table U will be U.N.

We called the extend.range() function by passing column T.A as its parameter:

table U = extend.range(T.A)

By doing so, we requested to extend the range of the target table U with as many lines as the value of the line in column T.A indicates: One line for the first line (1), one line for the second line (1) and three lines for the third line (3), where the process will start counting at 1 and then increment up to the value of the original line in T.A. Accordingly, we will receive the following output:

Example 2

table T[A] = with
  [| as A |]
  [| 1 |]
  [| 2 |]
  [| 3 |]

table U = extend.range(T.A)

show table "" a1c6 with
  U.A // This column has been implicitly copied by extend.range() from T.A
  U.N

Expected output of example 2

In this example, the table T actually does have a primary dimension T[A] and the values in the column T.A are now distinct, which is a prerequisite for creating a primary dimension. In these conditions, the T.A column will implicitly be copied to the new table U. The column U.N will be created according to the values of each line in T.A:

Expected fails

The function extend.range fails if:

• it receives a non-integer argument.
• it receives a negative argument (zero is valid).
• it would create more than 1 billion lines.

See also

• FIFO inventory method
• MOQs and other ordering constraints
• Secondary dimensions