pub fn lpmv_real(degree: f64, order: f64, x: f64) -> Result<f64>Expand description
Associated Legendre function P_degree^order(x) of a real argument, as a real value.
Outside [-1, 1] the odd orders with |order| <= degree have imaginary values: this
function rejects them, and angular_value returns them for a complex argument.
Orders with |order| > degree give zero.
Upstream: treams.special.lpmv with real arguments, which takes (order, degree, x).
Differences: for an integer degree, x outside [-1, 1] and 0 < |order| <= degree,
treams returns NaN, while this function returns the real value for even orders and an
error for odd orders. Degrees outside [0, 128], non-integer orders, non-finite x
and non-integer degrees with x outside (-1, 1] give an error, where treams returns
a value or NaN.