diff --git a/Signal Processing/Array Processing/MATLAB/Functions/firstOrderDma.m b/Signal Processing/Array Processing/MATLAB/Functions/firstOrderDma.m
index f31cdb6109f79086f2ed2996f168a1a64cbe1c9b..82e41684a4df40bb931b1904ecd8fc4c8534e32e 100644
--- a/Signal Processing/Array Processing/MATLAB/Functions/firstOrderDma.m	
+++ b/Signal Processing/Array Processing/MATLAB/Functions/firstOrderDma.m	
@@ -3,7 +3,7 @@
 % Author: Achilles Kappis
 % e-mail: axilleaz@protonmail.com
 %
-% Date: 05/11/2024 (DD/MM/YYYY)
+% Date: 17/11/2024 (DD/MM/YYYY)
 %
 % Copyright: MIT
 % --------------------------------------------------
@@ -77,8 +77,8 @@ function [h, output] = firstOrderDma(input, freq, d, pPattern, beta)
     % ====================================================
     validateattributes(input, {'numeric'}, {'3d', 'nonnan', 'finite', 'nonempty'}, mfilename, 'Input', 1);
 
-    if mod(size(input, 2), 2) ~= 0
-        error("Second dimension of 'input' parameter must have even length.")
+    if mod(size(input, 1), 2) ~= 0
+        error("First dimension of 'input' parameter must have even length.")
     end
 
     validateattributes(freq, {'numeric'}, {'real', 'nonnan', 'finite', 'nonempty', 'vector', 'numel', size(input, 3)}, mfilename, 'Frequencies', 2);