NORMINV

NORMINV(probability, mean, standard_dev)[source]

Calculates the inverse of the normal cumulative distribution.

NORMINV returns the value x such that the normal CDF evaluated at x equals the given probability, for the specified mean and standard deviation.

Parameters:
  • probability (Operand | int | float) –

    The probability value(s) for which to find the inverse (must be between 0 and 1).

    Supported types:

    • INTEGER

    • DECIMAL

    • INTEGER_ARRAY

    • DECIMAL_ARRAY

  • mean (Operand | int | float) –

    The arithmetic mean of the distribution.

    Supported types:

    • INTEGER

    • DECIMAL

    • INTEGER_ARRAY

    • DECIMAL_ARRAY

  • standard_dev (Operand | int | float) –

    The standard deviation of the distribution (must be > 0).

    Supported types:

    • INTEGER

    • DECIMAL

    • INTEGER_ARRAY

    • DECIMAL_ARRAY

Return type:

Formula

Returns:

A formula object evaluating to the inverse normal distribution value(s).

  • Returns DECIMAL if all inputs are scalar

  • Returns DECIMAL_ARRAY if any input is an array

Supported types:

  • DECIMAL

  • DECIMAL_ARRAY

Raises:

ValueError – If probability, mean, or standard_dev are not numeric types

Examples

Scalar inverse:

NORMINV(0.975, 0.0, 1.0)
# Returns ~1.96 (the 97.5th percentile of the standard normal distribution)

Array inputs:

NORMINV(my_table["probability"], 0.0, 1.0)
# Returns an array of inverse normal values for each row