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relationalai.std.math.atanh()

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.

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

An Expression object.

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