From be9ba38e1e17bb67a338f7cad01d5cb9c1d5715b Mon Sep 17 00:00:00 2001
From: cbaciocco <cbaciocco@usgs.gov>
Date: Thu, 19 May 2022 16:11:08 -0500
Subject: [PATCH] fix divide by zero avoidance in IHmethod's semilog
 interpolation

---
 pydrograph/baseflow.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/pydrograph/baseflow.py b/pydrograph/baseflow.py
index 4eeb9f3..6d1595d 100644
--- a/pydrograph/baseflow.py
+++ b/pydrograph/baseflow.py
@@ -203,8 +203,9 @@ def IHmethod(Qseries, block_length=5, tp=0.9, interp_semilog=True, freq='D', lim
     # interpolate between baseflow ordinates
     if interp_semilog:
         iszero = Q.ordinate.values == 0
-        logQ = np.log10(Q.ordinate)
-        logQ[iszero] = -2
+        logQ = Q.ordinate.copy()
+        logQ[iszero] = 0.01
+        logQ = np.log10(logQ)
         QB = np.power(10.0, logQ.interpolate(limit=limit).values)
     else:
         QB = Q.ordinate.interpolate(limit=limit).values