#### DistinctCount

Function

- DistinctCount(array_variable);
- DistinctCount(field_variable);
- DistinctCount(field_variable, groupby);

Description

This function is used to count the number of distinct values referred to by the first argument together. The second argument, if there is one, gives the group by field name.

Arguments

- field_variable
  field_variable is a special variable in Formula, and refers to a group of values from a database or formula field.
- array_variable
  array_variable refers to an array whose element should be a Number.
- groupby
  groupby can be a constant String to indicate the groupby field name, or a field variable on which grouping occurs, or a parameter variable that can accept a different value before each execution of a report.

Return type

Returns a Number value.

Examples

- `Number x = DistinctCount([1.0, 1.0, 3.0, 4.5, 4.5, 67.0]) // result is 4`
- `Number x[6] = [1.0, 1.0, 3.0, 4.5, 4.5, 67.0];
  Number y = DistinctCount(x)`
- `Number x = DistinctCount(["str1","str1","str3","str4","str4","str6"])}`
- `Number x = DistinctCount(@dbfield)`
- `Number x = DistinctCount(@formula)`
- `Number x = DistinctCount(@dbfield, "group_field")`
- `Number x = DistinctCount(@formula, @"group_field")`
- `Number x = DistinctCount(@dbfield, @parameter)`

Note: If a field_variable is assigned to a variable, for example X, the variable X will lose the characteristic of representing a group of values. The following formula will then be treated as incorrect.

`Number x = @dbfield;
Number y = DistinctCount(x); // system will prompt you that there is no such kind of function.`