From 736cad84cfbc3993a3a38c640690442f4aaa4cf2 Mon Sep 17 00:00:00 2001
From: Juniper Tyree <50025784+juntyr@users.noreply.github.com>
Date: Tue, 8 Oct 2024 09:42:09 +0300
Subject: [PATCH 1/3] Improve levels auto_range with proper symmetry

---
 src/earthkit/plots/styles/levels.py | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/src/earthkit/plots/styles/levels.py b/src/earthkit/plots/styles/levels.py
index 5527ddc..c1ee8e9 100644
--- a/src/earthkit/plots/styles/levels.py
+++ b/src/earthkit/plots/styles/levels.py
@@ -57,22 +57,18 @@ def auto_range(data, divergence_point=None, n_levels=schema.default_style_levels
 
     initial_bin = data_range / n_levels
 
-    magnitude = 10 ** (math.floor(math.log(initial_bin, 10)))
+    magnitude = 10 ** (np.floor(np.log10(initial_bin)))
     bin_width = initial_bin - (initial_bin % -magnitude)
 
-    start = min_value - (min_value % magnitude)
+    min_value -= min_value % bin_width
+    max_value -= max_value % -bin_width
 
-    levels = np.arange(
-        start,
-        start + (bin_width * n_levels) + bin_width,
-        bin_width,
+    return np.linspace(
+        min_value,
+        max_value,
+        n_levels + 1,
     ).tolist()
 
-    while levels[-2] >= max_value:
-        levels = levels[:-1]
-
-    return levels
-
 
 def step_range(data, step, reference=None):
     """

From af6d94441e1fe1ee89ee0f138bcafd9c4666a2e0 Mon Sep 17 00:00:00 2001
From: Juniper Tyree <50025784+juntyr@users.noreply.github.com>
Date: Tue, 8 Oct 2024 09:49:25 +0300
Subject: [PATCH 2/3] Ensure symmetry around arbitrary divergence point

---
 src/earthkit/plots/styles/levels.py | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/earthkit/plots/styles/levels.py b/src/earthkit/plots/styles/levels.py
index c1ee8e9..169a23b 100644
--- a/src/earthkit/plots/styles/levels.py
+++ b/src/earthkit/plots/styles/levels.py
@@ -50,8 +50,8 @@ def auto_range(data, divergence_point=None, n_levels=schema.default_style_levels
 
     if divergence_point is not None:
         max_diff = max(max_value - divergence_point, divergence_point - min_value)
-        max_value = divergence_point + max_diff
-        min_value = divergence_point - max_diff
+        max_value = max_diff
+        min_value = -max_diff
 
     data_range = max_value - min_value
 
@@ -63,6 +63,10 @@ def auto_range(data, divergence_point=None, n_levels=schema.default_style_levels
     min_value -= min_value % bin_width
     max_value -= max_value % -bin_width
 
+    if divergence_point is not None:
+        min_value += divergence_point
+        max_value += divergence_point
+
     return np.linspace(
         min_value,
         max_value,

From 06b6c96dd2d8c3743fbc66e23a254be801f80ff8 Mon Sep 17 00:00:00 2001
From: James Varndell <james.varndell@ecmwf.int>
Date: Fri, 18 Oct 2024 17:35:20 +0100
Subject: [PATCH 3/3] Removes obsolete math import

---
 src/earthkit/plots/styles/levels.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/earthkit/plots/styles/levels.py b/src/earthkit/plots/styles/levels.py
index 169a23b..730dd2b 100644
--- a/src/earthkit/plots/styles/levels.py
+++ b/src/earthkit/plots/styles/levels.py
@@ -12,8 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import math
-
 import numpy as np
 
 from earthkit.plots.schemas import schema