From f284e15a5705d13e62706317f7e47f0e9b3fac7f Mon Sep 17 00:00:00 2001
From: Ansgar Wehrhahn <31626864+AWehrhahn@users.noreply.github.com>
Date: Wed, 2 Jun 2021 17:32:24 +0200
Subject: [PATCH] improved continuum fit

---
 src/pysme/continuum_and_radial_velocity.py | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/pysme/continuum_and_radial_velocity.py b/src/pysme/continuum_and_radial_velocity.py
index 423c92d8..b03503e7 100644
--- a/src/pysme/continuum_and_radial_velocity.py
+++ b/src/pysme/continuum_and_radial_velocity.py
@@ -676,12 +676,11 @@ def cont_fit(sme, segment, x_syn, y_syn, rvel=0, only_mask=False):
 
     deg = sme.cscale_degree
     p0 = sme.cscale[segment]
-    func = lambda x, *p: yp * np.polyval(p, x)
+    func = lambda x, *p: (yp * np.polyval(p, xs) - y) / u
     try:
-        popt, pcov = curve_fit(
-            func, xs, y, sigma=u, p0=p0, loss="soft_l1", method="trf", xtol=None
-        )
-    except RuntimeError:
+        res = least_squares(func, x0=p0, loss="soft_l1", method="trf", xtol=None)
+        popt = res.x
+    except RuntimeError as ex:
         logger.warning("Could not determine the continuum")
         popt = p0
     # popt = res.x