Function kappa_sigma_clamp 

pub fn kappa_sigma_clamp(
    z: &mut [Number],
    slack: &[Number],
    mu: Number,
    kappa_sigma: Number,
) -> Number

Per-element kappa-sigma clamp — the elementwise arithmetic at the heart of IpIpoptAlg.cpp:correct_bound_multiplier (lines 1090-1133). For each index i:

  slack_i  = max(slack_i, tiny_double)   // avoid /0
  z_lo_i   = mu / (kappa_sigma * slack_i)
  z_hi_i   = kappa_sigma * mu / slack_i
  z_i      ← clamp(z_i, z_lo_i, z_hi_i)

Returns the maximum elementwise correction magnitude (matching upstream’s Max(max_correction_up, max_correction_low)).

kappa_sigma < 1 short-circuits to the identity per upstream’s guard at line 1065.