From 9c6849a3729dc4ca1301dd23403df9c09bc177c3 Mon Sep 17 00:00:00 2001
From: Sonu0305 <swayamshah66@gmail.com>
Date: Mon, 14 Sep 2026 15:21:20 +0400
Subject: [PATCH 1/4] Fix empty array edge cases in mvregress

---
 inst/Regression/mvregress.m | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/inst/Regression/mvregress.m b/inst/Regression/mvregress.m
index 7e55d7525..a73c5bf90 100644
--- a/inst/Regression/mvregress.m
+++ b/inst/Regression/mvregress.m
@@ -75,6 +75,9 @@
     error ("mvregress: Y must be a real numeric matrix.");
   endif
   [n, d] = size (Y);
+  if (n == 0 || d == 0)
+    error ("mvregress: Y array is empty - cannot continue.");
+  endif
 
   ## --- normalise the design to per-observation d-by-K matrices ---
   is_numeric = ! iscell (X);
@@ -431,5 +434,12 @@
 %!error <Invalid call> mvregress (1)
 %!error <Y must be a real numeric matrix> mvregress (ones (3), {1})
 %!error <X must have as many rows as Y> mvregress (ones (2, 2), ones (3, 2))
+
+%!test
+%! ## Edge cases with empty arrays
+%!fail ("mvregress ([], [])", ...
+%!      "mvregress: Y array is empty - cannot continue.")
+%!fail ("mvregress (zeros(0,3), zeros(0,1))", ...
+%!      "mvregress: Y array is empty - cannot continue.")
 %!error <algorithm must be> mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
 %!error <unknown option 'bogus'> mvregress (ones (3, 2), ones (3, 2), "bogus", 1)

From 0704dca8a9882c34848109a86b0b334733376150 Mon Sep 17 00:00:00 2001
From: Sonu0305 <swayamshah66@gmail.com>
Date: Mon, 14 Sep 2026 15:56:17 +0400
Subject: [PATCH 2/4] Refactor tests to use %!error instead of %!fail

---
 inst/Regression/mvregress.m | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/inst/Regression/mvregress.m b/inst/Regression/mvregress.m
index a73c5bf90..d051486fb 100644
--- a/inst/Regression/mvregress.m
+++ b/inst/Regression/mvregress.m
@@ -437,9 +437,9 @@
 
 %!test
 %! ## Edge cases with empty arrays
-%!fail ("mvregress ([], [])", ...
-%!      "mvregress: Y array is empty - cannot continue.")
-%!fail ("mvregress (zeros(0,3), zeros(0,1))", ...
-%!      "mvregress: Y array is empty - cannot continue.")
+%!error<mvregress: Y array is empty - cannot continue.> ...
+%! mvregress ([], [])
+%!error<mvregress: Y array is empty - cannot continue.> ...
+%! mvregress (zeros(0,3), zeros(0,1))
 %!error <algorithm must be> mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
 %!error <unknown option 'bogus'> mvregress (ones (3, 2), ones (3, 2), "bogus", 1)

From 521ba2c1ee9a80b9fb83280b3b5c4a7e571bfc2a Mon Sep 17 00:00:00 2001
From: Sonu0305 <swayamshah66@gmail.com>
Date: Tue, 15 Sep 2026 20:57:50 +0400
Subject: [PATCH 3/4] Update empty array error message for mvregress

---
 inst/Regression/mvregress.m | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/inst/Regression/mvregress.m b/inst/Regression/mvregress.m
index d051486fb..eed454439 100644
--- a/inst/Regression/mvregress.m
+++ b/inst/Regression/mvregress.m
@@ -76,7 +76,7 @@
   endif
   [n, d] = size (Y);
   if (n == 0 || d == 0)
-    error ("mvregress: Y array is empty - cannot continue.");
+    error ("mvregress: y cannot be an empty array.");
   endif
 
   ## --- normalise the design to per-observation d-by-K matrices ---
@@ -434,12 +434,11 @@
 %!error <Invalid call> mvregress (1)
 %!error <Y must be a real numeric matrix> mvregress (ones (3), {1})
 %!error <X must have as many rows as Y> mvregress (ones (2, 2), ones (3, 2))
-
-%!test
-%! ## Edge cases with empty arrays
-%!error<mvregress: Y array is empty - cannot continue.> ...
+%!error <mvregress: y cannot be an empty array.> ...
 %! mvregress ([], [])
-%!error<mvregress: Y array is empty - cannot continue.> ...
+%!error <mvregress: y cannot be an empty array.> ...
 %! mvregress (zeros(0,3), zeros(0,1))
-%!error <algorithm must be> mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
-%!error <unknown option 'bogus'> mvregress (ones (3, 2), ones (3, 2), "bogus", 1)
+%!error <algorithm must be> ...
+%! mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
+%!error <unknown option 'bogus'> ...
+%! mvregress (ones (3, 2), ones (3, 2), "bogus", 1)

From 4b1adbbe79d21c9bbfcbf7524b15124c3bfddcb0 Mon Sep 17 00:00:00 2001
From: Sonu0305 <swayamshah66@gmail.com>
Date: Wed, 16 Sep 2026 06:24:44 +0400
Subject: [PATCH 4/4] Fix case in mvregress error and restore test formatting

---
 inst/Regression/mvregress.m | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/inst/Regression/mvregress.m b/inst/Regression/mvregress.m
index eed454439..f13467c53 100644
--- a/inst/Regression/mvregress.m
+++ b/inst/Regression/mvregress.m
@@ -75,8 +75,8 @@
     error ("mvregress: Y must be a real numeric matrix.");
   endif
   [n, d] = size (Y);
-  if (n == 0 || d == 0)
-    error ("mvregress: y cannot be an empty array.");
+  if (isempty (Y))
+    error ("mvregress: Y cannot be an empty array.");
   endif
 
   ## --- normalise the design to per-observation d-by-K matrices ---
@@ -434,11 +434,9 @@
 %!error <Invalid call> mvregress (1)
 %!error <Y must be a real numeric matrix> mvregress (ones (3), {1})
 %!error <X must have as many rows as Y> mvregress (ones (2, 2), ones (3, 2))
-%!error <mvregress: y cannot be an empty array.> ...
+%!error <mvregress: Y cannot be an empty array.> ...
 %! mvregress ([], [])
-%!error <mvregress: y cannot be an empty array.> ...
-%! mvregress (zeros(0,3), zeros(0,1))
-%!error <algorithm must be> ...
-%! mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
-%!error <unknown option 'bogus'> ...
-%! mvregress (ones (3, 2), ones (3, 2), "bogus", 1)
+%!error <mvregress: Y cannot be an empty array.> ...
+%! mvregress (zeros (0, 3), zeros (0, 1))
+%!error <algorithm must be> mvregress (ones (3, 2), ones (3, 2), "algorithm", "xxx")
+%!error <unknown option 'bogus'> mvregress (ones (3, 2), ones (3, 2), "bogus", 1)