atanh()#

relationalai.std.math
#atanh(number: Number|Producer) -> Expression

Calculates the inverse hyperbolic tangent (arctanh) of a number. The input number must be in the range -1 to 1. If number is a Producer, atanh() filters out any non-numeric or invalid values from the producer. Must be called in a rule or query context.

Parameters#

NameTypeDescription
numberProducer or Python Number objectThe value to calculate the inverse hyperbolic tangent of, must be in the range -1 to 1.

Returns#

An Expression object.

Example#

Use atanh() to calculate the inverse hyperbolic tangent of a number:

#import relationalai as rai
from relationalai.std import math


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

model = rai.Model("MyModel")
Portfolio = model.Type("Portfolio")
Investment = model.Type("Investment")

# Define portfolios and their investments.
with model.rule():
    portfolio1 = Portfolio.add(id=1).set(name="Portfolio1")
    portfolio1.investments.extend([
        Investment.add(id=1).set(name="InvestmentA", growth_rate=0.5),
        Investment.add(id=2).set(name="InvestmentB", growth_rate=0.9),
    ])

    portfolio2 = Portfolio.add(id=2).set(name="Portfolio2")
    portfolio2.investments.extend([
        Investment.add(id=3).set(name="InvestmentC", growth_rate=0.3),
        Investment.add(id=4).set(name="InvestmentD", growth_rate=1.2),  # Out of range
    ])


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

# Set a growth_atanh property to the inverse hyperbolic tangent of each investment's growth rate.
with model.rule():
    portfolio = Portfolio()
    investment = portfolio.investments
    investment.set(growth_atanh=math.atanh(investment.growth_rate))

# Since atanh() filters out non-numeric or out-of-range values, the growth_atanh
# property is not set for the investment with ID 4.
with model.query() as select:
    portfolio = Portfolio()
    investment = portfolio.investments
    response = select(portfolio.name, investment.name, investment.growth_atanh)

print(response.results)
#          name        name2  growth_atanh
# 0  Portfolio1  InvestmentA      0.549306
# 1  Portfolio1  InvestmentB      1.472219
# 2  Portfolio2  InvestmentC      0.309520
# 3  Portfolio2  InvestmentD           NaN

See Also#