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relationalai.std.math.cbrt()

cbrt(value: Number|Producer) -> Expression

Calculates the cube root of value. If value is a Producer, cbrt() acts as a filter and removes any non-numeric values from the producer. Must be called in a rule or query context.

Parameters

Name	Type	Description
`value`	`Producer` or Python `Number` object	The number to take the cube root of.

Returns

An Expression object.

Example

Use cbrt() to calculate the cube root of a number:

import relationalai as rai
from relationalai.std import math


# =====
# SETUP
# =====

model = rai.Model("MyModel")
Account = model.Type("Account")

with model.rule():
    Account.add(id=1).set(balance=27.0)
    Account.add(id=2).set(balance=-64.0)  # Negative balance
    Account.add(id=3).set(balance="INVALID")  # Non-numeric balance


# =======
# EXAMPLE
# =======

# Set a balance_cbrt property to the cube root of each account's balance.
with model.rule():
    account = Account()
    account.set(balance_cbrt=math.cbrt(account.balance))

# Since cbrt() filters out non-numeric values, the balance_cbrt
# property is not set for the account with ID 3.
with model.query() as select:
    account = Account()
    response = select(account.id, account.balance_cbrt)

print(response.results)
#    id  balance_cbrt
# 0   1           3.0
# 1   2          -4.0
# 2   3           NaN

See Also