From 6f70e5f59953940187cb4ebc35041232ca7b4d6c Mon Sep 17 00:00:00 2001
From: Mike McCann <MBARIMike@gmail.com>
Date: Wed, 26 Mar 2025 12:13:53 -0700
Subject: [PATCH] Revert back to original hs2_calc_bb() - the translation from
 the Sackmann Matlab code.

---
 .vscode/launch.json  |  4 ++--
 src/data/hs2_proc.py | 36 +++++++++++++++++++++++++++---------
 2 files changed, 29 insertions(+), 11 deletions(-)

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 61943baa..8e337122 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -226,7 +226,7 @@
             //"args": ["-v", "1", "--last_n_days", "30", "--start_year", "2022", "--end_year", "2022", "--resample", "--noinput"]
             //"args": ["-v", "1", "--last_n_days", "30", "--start_year", "2022", "--end_year", "2022", "--archive", "--noinput"]
             //"args": ["-v", "1", "--start_year", "2021", "--end_year", "2022",  "--noinput"]
-            //"args": ["-v", "1", "--mission", "2022.201.00", "--clobber", "--noinput", "--no_cleanup"]
+            "args": ["-v", "1", "--mission", "2022.201.00", "--clobber", "--noinput", "--no_cleanup"]
             //"args": ["-v", "1", "--mission", "2009.084.00",  "--clobber", "--noinput"]
             //"args": ["-v", "1", "--mission", "2022.243.00",  "--calibrate", "--clobber", "--noinput"]
             //"args": ["-v", "1", "--start_year", "2004",  "--end_year", "2004", "--start_yd", "168", "--use_portal", "--clobber", "--noinput"]
@@ -265,7 +265,7 @@
             //"args": ["-v", "1", "--noinput", "--num_cores", "8"]
             //"args": ["-v", "1", "--noinput", "--no_cleanup",  "--mission", "2011.256.02", "--clobber"]
             //"args": ["-v", "1", "--noinput", "--no_cleanup",  "--mission", "2010.341.00", "--download_process", "--local"]
-            "args": ["-v", "1", "--noinput", "--no_cleanup",  "--mission", "2020.337.00", "--local"]
+            //"args": ["-v", "1", "--noinput", "--no_cleanup",  "--mission", "2020.337.00", "--local"]
         },
     ]
 }
diff --git a/src/data/hs2_proc.py b/src/data/hs2_proc.py
index 029a7d6d..f2869bb8 100644
--- a/src/data/hs2_proc.py
+++ b/src/data/hs2_proc.py
@@ -1,7 +1,7 @@
 # noqa: INP001
 
 from collections import defaultdict
-from math import exp
+from math import exp, pi
 from pathlib import Path
 
 import numpy as np
@@ -164,15 +164,30 @@ def hs2_calc_bb(orig_nc, cals):
             (_int_signer(orig_nc[f"Snorm{chan}"]) * float(cals[f"Ch{chan}"]["Mu"])),
             denom,
         )
-        # Replaces "RawTempValue" as the name, helpful when looking at things in the debugger
-        beta_uncorr.name = f"beta_uncorr_Ch{chan}"
         wavelength = int(cals[f"Ch{chan}"]["Name"][2:])
+        beta_w, b_bw = purewater_scatter(wavelength)
 
-        # Use compute_backscatter - same as used for ecopucks - to calculate bbp
-        _, bbp = compute_backscatter(wavelength, 35.2, beta_uncorr)
-        setattr(hs2, f"bbp{wavelength}", bbp)
+        chi = 1.08
+        b_b_uncorr = ((2 * pi * chi) * (beta_uncorr - beta_w)) + b_bw
+
+        globals()[f"bb{wavelength}_uncorr"] = b_b_uncorr
+        globals()[f"bbp{wavelength}_uncorr"] = b_b_uncorr - b_bw
+
+        # ESTIMATION OF KBB AND SIGMA FUNCTION
+        a = typ_absorption(wavelength)
+        b_b_tilde = 0.015
+        b = (b_b_uncorr - b_bw) / b_b_tilde
+
+        K_bb = a + 0.4 * b
+        k_1 = 1.0
+        k_exp = float(cals[f"Ch{chan}"]["SigmaExp"])
+        sigma = k_1 * np.exp(k_exp * K_bb)
+
+        b_b_corr = sigma * b_b_uncorr
+
+        setattr(hs2, f"bb{wavelength}", b_b_corr)
+        setattr(hs2, f"bbp{wavelength}", b_b_corr - b_bw)
 
-    # Fluorescence
     # -% 'hs2.fl700_uncorr = (hs2.Snorm3.*50)./((1 + str2num(CAL.Ch(3).TempCoeff).*(hs2.Temp-str2num(CAL.General.CalTemp))).*hs2.Gain3.*str2num(CAL.Ch(3).RNominal));'  # noqa: E501
     denom = (
         (
@@ -186,8 +201,11 @@ def hs2_calc_bb(orig_nc, cals):
     snorm3 = _int_signer(orig_nc["Snorm3"])
     setattr(hs2, f"fl{wavelength}", np.divide(snorm3 * 50, denom))
 
-    hs2.caldepth = float(cals["General"]["DepthCal"]) * orig_nc["RawDepthValue"] - float(
-        cals["General"]["DepthOff"]
+    setattr(  # noqa: B010
+        hs2,
+        "caldepth",
+        float(cals["General"]["DepthCal"]) * orig_nc["RawDepthValue"]
+        - float(cals["General"]["DepthOff"]),
     )
 
     return hs2