From 9131bdfdcc5401a69f77349bb54241365cfaa508 Mon Sep 17 00:00:00 2001
From: CAOShurong <170531907+CAOShurong@users.noreply.github.com>
Date: Wed, 14 Oct 2026 15:01:59 +0800
Subject: [PATCH] Fix column-major ordering of multidimensional text waves

---
 CHANGELOG            |   2 ++
 igor2/binarywave.py  |   2 +-
 tests/data/README    |   5 +++++
 tests/data/text3.ibw | Bin 0 -> 456 bytes
 tests/test_ibw.py    |  12 ++++++++++++
 5 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 tests/data/text3.ibw

diff --git a/CHANGELOG b/CHANGELOG
index 5752791..69669c9 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+Unreleased
+ - fix: preserve column-major ordering of multidimensional text waves (#25)
 0.5.13
  - fix: thread safety issues and add better concurrent tests (#27)
 0.5.12
diff --git a/igor2/binarywave.py b/igor2/binarywave.py
index 4e831e8..373cba1 100644
--- a/igor2/binarywave.py
+++ b/igor2/binarywave.py
@@ -602,7 +602,7 @@ def post_unpack(self, parents, data):
         wdata = _numpy.array(strings)
         shape = [n for n in wave_header['nDim'] if n > 0] or (0,)
         try:
-            wdata = wdata.reshape(shape)
+            wdata = wdata.reshape(shape, order='F')
         except ValueError:
             logger.error(
                 'could not reshape strings from %s to %s',
diff --git a/tests/data/README b/tests/data/README
index 7ec9646..e206810 100644
--- a/tests/data/README
+++ b/tests/data/README
@@ -2,3 +2,8 @@
 
 polar-graphs-demo.pxp was distributed with IGOR Pro 5.04 as
   Examples/Graphing Techniques/Obsolete/Polar Graphs Demo.pxp
+
+text3.ibw was provided by jbemis99 in issue #25:
+https://github.com/AFM-analysis/igor2/issues/25
+The 3-by-2 text wave contains columns (cat, dog, fish) and
+(tiger, wolf, shark), as shown by the reporter in Igor Pro.
diff --git a/tests/data/text3.ibw b/tests/data/text3.ibw
new file mode 100644
index 0000000000000000000000000000000000000000..aeb7d65d60bafbc3f27a71f4fa636dc8236b2427
GIT binary patch
literal 456
zcmZQ&Q2!Od$N&Zs5Q-p)tS%!;oX1+E{0RuNA#^e`Gcz)jq*jy|BgC+>5_WU(Fau?n
zFl0a2LxgbA7#au&JY^xE0IT$gXmK7U24)6m5MfnAND!nOroY~RfdS@_6+p9-6H8L^
z)6+7GGfFbkQ;W*;bJB`45{t4yVW*IiSdyraS*(y+mYS!Klb;7v017KmICB9pKM)H8
HF(^I&`+Oxk

literal 0
HcmV?d00001

diff --git a/tests/test_ibw.py b/tests/test_ibw.py
index 6a1755f..bbdadf2 100644
--- a/tests/test_ibw.py
+++ b/tests/test_ibw.py
@@ -1,4 +1,5 @@
 from helper import assert_equal_dump_no_whitespace_no_byte, dumpibw
+from helper import data_dir, loadibw
 
 
 def test_ibw01():
@@ -629,3 +630,14 @@ def test_ibw_10():
                               'whpad4': 0}}}
     """
     assert_equal_dump_no_whitespace_no_byte(act, exp)
+
+
+def test_multidimensional_text_wave():
+    data = loadibw(data_dir / 'text3.ibw')['wave']['wData']
+
+    assert data.shape == (3, 2)
+    assert data.tolist() == [
+        [b'cat', b'tiger'],
+        [b'dog', b'wolf'],
+        [b'fish', b'shark'],
+    ]