Edit: Fix loading datetime with complex valued data in MAT-files

src/MAT_types.jl

@@ -494,7 +494,7 @@ end
 ms_to_datetime(ms::Complex) = ms_to_datetime(real(ms))
 function ms_to_datetime(ms::Real)
     s, ms_rem = fldmod(ms, 1_000)  # whole seconds and remainder milliseconds
-    return DateTime(1970, 1, 1) + Second(s) + Millisecond(ms_rem)
+    return DateTime(1970, 1, 1) + Second(s) + Millisecond(round(Int, ms_rem))
 end
 
 function to_matlab_data(d::DateTime)

test/read.jl

@@ -273,6 +273,10 @@ for format in ["v7", "v7.3"]
         @test dt isa DateTime
         @test dt - DateTime(2019, 12, 2, 16, 42, 49) < Second(1)
 
+        @test "testDatetimeComplex" in keys(vars)
+        dtc = vars["testDatetimeComplex"]
+        @test dtc isa DateTime
+
         # test no conversion at all
         vars = matread(filepath; convert_opaque=false)["s"]
         t = vars["testTable"]