From 85f0712755afeb2bcd9709a069f0d1003ffd202c Mon Sep 17 00:00:00 2001
From: Marta Han <marta.han@sed.ethz.ch>
Date: Fri, 7 Jun 2024 16:11:18 +0200
Subject: [PATCH] adding sorting by time to Catalog.estimate_b() when
 b-positive method is applied

---
 seismostats/seismicity/catalog.py | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/seismostats/seismicity/catalog.py b/seismostats/seismicity/catalog.py
index c3ef4d6..1c553f9 100644
--- a/seismostats/seismicity/catalog.py
+++ b/seismostats/seismicity/catalog.py
@@ -362,7 +362,16 @@ def estimate_b(
         if delta_m is None:
             delta_m = self.delta_m
 
-        b_estimate = estimate_b(self.magnitude,
+        if method == "positive":
+            # dataframe needs 'time' column to be sorted
+            if 'time' not in self.columns:
+                raise ValueError('"time" column needs to be set in order to use \
+                                 b-positive method')
+            mags = self.sort_values("time").magnitude
+        else:
+            mags = self.magnitude
+
+        b_estimate = estimate_b(mags,
                                 mc,
                                 delta_m,
                                 weights,