where() Function

Function

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where( booleanArray, default )

Returns the indexes where the values in the input array are true.

See also:

• wherecontains(): Use this function to return indexes of an array that match a user-defined value, instead of items that evaluate to true.
• index(): Use this function to return the values of an array at the indexes you gathered with the where() function.

Parameters

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Returns

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Integer Array

Usage considerations

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When to use where()

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This function is useful for finding values in an array that meet a certain criterion. It's also useful for checking the value of a field in an array of CDT field values.

Understanding results

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If a default value is not specified and none of the values in the input array are true, an empty list will be returned.

A null or empty array given as the array parameter is considered false.

Examples

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Check which indexes are true

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where({true, false, true})
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Returns 1, 3.

When all array values are false and no default is specified, an empty set is returned. For example:

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where({false, false, false})
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Returns {}.

When all array values are false and a default is specified, the default value is returned. For example:

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where({false, false, false}, -1)
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Returns {-1}.

Check which indexes are even

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where(mod({13, 24, 35, 46, 57, 68}, 2)=0)
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Returns 2, 4, 6. mod({13, 24, 35, 46, 57, 68}, 2)=0 returns a list of true and false values based on whether a value is divisible by 2. The where() function then returns the list of indexes for true values (in this example, the even numbers).

Use with comparison operators

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Check which indexes are greater than 50

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a!localVariables(
  local!scores: {68, 89, 82, 90, 93, 99, 59, 49, 88, 27, 56, 49, 100},
  where(local!scores < 50)
)
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Returns {8, 10, 12}.

Check which indexes are greater than the average

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a!localVariables(
  local!scores: {68, 89, 82, 90, 93, 99, 59, 49, 88, 27, 56, 49, 100},
  where(local!scores > average(local!scores))
)
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Returns {2, 3, 4, 5, 6, 9, 13}.

Check which indexes are less than three standard deviations from the mean

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a!localVariables(
  local!scores: {68, 89, 82, 90, 93, 99, 59, 49, 88, 27, 56, 49, 100},
  where(
    local!scores < average(local!scores) - 3 * stdevp(local!scores),
    -1
  )
)
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Returns -1 because no scores are less than three standard deviations from the mean.

Use with the index() function

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Return first name of employees in a specified department

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index(
  ri!employees.firstName,
  where(
    like(ri!employees.department, "Finance"),
    -1
  ),
  "None"
)
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Returns all of the first names of employees in the Finance department, or "None" if none of the employees have their department field set to Finance.

Return customers with risk scores greater than 15

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a!localVariables(
  local!customer: {
    'type!Customer'(riskScore: 1),
    'type!Customer'(riskScore: 25),
    'type!Customer'(),
    'type!Customer'(riskScore: 15),
    
  },
  local!customer[where(local!customer.riskScore > 10)]
)
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Returns the customer CDTs from the original list with risk scores greater than 15 (the second and fourth customers).

Use with a null or empty array

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Null booleanArray

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where(null)
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Returns {}.

Null booleanArray with default

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where(null, 1000)
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Returns {1000}.

Empty booleanArray

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where({})
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Returns {}.

Empty booleanArray with default

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where({}, -1)
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Returns {-1}

booleanArray with null item

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where({true, false, null, true})
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Returns {1, 4}

Feature compatibility

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Feedback

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