From d52675fb23bf5b253383ab393bcf05fbb7c500a5 Mon Sep 17 00:00:00 2001
From: Nelle Varoquaux <nelle.varoquaux@gmail.com>
Date: Sun, 23 Oct 2016 11:17:26 -0700
Subject: [PATCH 1/3] FIX symlog scale now shows negative labels.

The formatter returned empty strings for negative value.

closes #7146
---
 lib/matplotlib/tests/test_ticker.py | 3 +--
 lib/matplotlib/ticker.py            | 4 ++--
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/lib/matplotlib/tests/test_ticker.py b/lib/matplotlib/tests/test_ticker.py
index 78d693adeaad..4c4cdb3c4498 100644
--- a/lib/matplotlib/tests/test_ticker.py
+++ b/lib/matplotlib/tests/test_ticker.py
@@ -1,8 +1,6 @@
 from __future__ import (absolute_import, division, print_function,
                         unicode_literals)
 
-import six
-
 from numpy.testing import assert_almost_equal
 import numpy as np
 import pytest
@@ -305,6 +303,7 @@ def test_LogFormatterExponent_blank():
 def test_LogFormatterSciNotation():
     test_cases = {
         10: (
+             (-1, '${-10^{0}}$'),
              (1e-05, '${10^{-5}}$'),
              (1, '${10^{0}}$'),
              (100000, '${10^{5}}$'),
diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
index 102a7988fc21..e1198e36795b 100644
--- a/lib/matplotlib/ticker.py
+++ b/lib/matplotlib/ticker.py
@@ -902,7 +902,7 @@ def __call__(self, x, pos=None):
         fx = math.log(abs(x)) / math.log(b)
         isDecade = is_close_to_int(fx)
         exponent = np.round(fx) if isDecade else np.floor(fx)
-        coeff = np.round(x / b ** exponent)
+        coeff = np.round(abs(x) / b ** exponent)
         if coeff in self.sublabel:
             if not isDecade and self.labelOnlyBase:
                 s = ''
@@ -1032,7 +1032,7 @@ def __call__(self, x, pos=None):
         fx = math.log(abs(x)) / math.log(b)
         is_decade = is_close_to_int(fx)
         exponent = np.round(fx) if is_decade else np.floor(fx)
-        coeff = np.round(x / b ** exponent)
+        coeff = np.round(abs(x) / b ** exponent)
 
         sign_string = '-' if x < 0 else ''
 

From 46083bfd5503b4feab7ef02998d559dc75f52f30 Mon Sep 17 00:00:00 2001
From: Nelle Varoquaux <nelle.varoquaux@gmail.com>
Date: Mon, 24 Oct 2016 11:52:38 -0400
Subject: [PATCH 2/3] FIX more fixes for tickers

---
 lib/matplotlib/ticker.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
index e1198e36795b..4363454472a9 100644
--- a/lib/matplotlib/ticker.py
+++ b/lib/matplotlib/ticker.py
@@ -905,11 +905,11 @@ def __call__(self, x, pos=None):
         coeff = np.round(abs(x) / b ** exponent)
         if coeff in self.sublabel:
             if not isDecade and self.labelOnlyBase:
-                s = ''
+                return ''
             elif x > 10000:
-                s = '%1.0e' % x
+                s = '%1.0e' % abs(x)
             elif x < 1:
-                s = '%1.0e' % x
+                s = '%1.0e' % abs(x)
             else:
                 s = self.pprint_val(x, self.d)
             if sign == -1:

From 0199251bc5f871354171d28787962070c22e3aae Mon Sep 17 00:00:00 2001
From: Nelle Varoquaux <nelle.varoquaux@gmail.com>
Date: Mon, 24 Oct 2016 15:49:16 -0400
Subject: [PATCH 3/3] FIX negative value for log formatter is now better dealt
 with

---
 lib/matplotlib/ticker.py | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
index 4363454472a9..c11f1b214bb7 100644
--- a/lib/matplotlib/ticker.py
+++ b/lib/matplotlib/ticker.py
@@ -898,18 +898,19 @@ def __call__(self, x, pos=None):
         if x == 0.0:
             return '0'
         sign = np.sign(x)
+        x = abs(x)
         # only label the decades
-        fx = math.log(abs(x)) / math.log(b)
+        fx = math.log(x) / math.log(b)
         isDecade = is_close_to_int(fx)
         exponent = np.round(fx) if isDecade else np.floor(fx)
-        coeff = np.round(abs(x) / b ** exponent)
+        coeff = np.round(x / b ** exponent)
         if coeff in self.sublabel:
             if not isDecade and self.labelOnlyBase:
                 return ''
             elif x > 10000:
-                s = '%1.0e' % abs(x)
+                s = '%1.0e' % x
             elif x < 1:
-                s = '%1.0e' % abs(x)
+                s = '%1.0e' % x
             else:
                 s = self.pprint_val(x, self.d)
             if sign == -1: