diff --git a/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/EjmlVector.kt b/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/EjmlVector.kt
index 82401ba05..4056d419b 100644
--- a/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/EjmlVector.kt
+++ b/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/EjmlVector.kt
@@ -18,7 +18,7 @@ import space.kscience.kmath.linear.Point
  */
 public abstract class EjmlVector<out T, out M : Matrix>(public open val origin: M) : Point<T> {
     override val size: Int
-        get() = origin.numCols
+        get() = origin.numRows
 
     override operator fun iterator(): Iterator<T> = object : Iterator<T> {
         private var cursor: Int = 0
diff --git a/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/implementations.kt b/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/implementations.kt
index f831f495f..fa6db7817 100644
--- a/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/implementations.kt
+++ b/kmath-ejml/src/jvmMain/kotlin/space/kscience/kmath/ejml/implementations.kt
@@ -45,11 +45,11 @@ public fun Complex_F64.toKMathComplex(): Complex = Complex(real, imaginary)
  */
 public class EjmlDoubleVector<out M : DMatrix>(override val origin: M) : EjmlVector<Double, M>(origin) {
     init {
-        require(origin.numRows == 1) { "The origin matrix must have only one row to form a vector" }
+        require(origin.numCols == 1) { "The origin matrix must have only one column to form a vector" }
     }
 
 
-    override operator fun get(index: Int): Double = origin[0, index]
+    override operator fun get(index: Int): Double = origin[index, 0]
 }
 
 /**
@@ -57,10 +57,10 @@ public class EjmlDoubleVector<out M : DMatrix>(override val origin: M) : EjmlVec
  */
 public class EjmlFloatVector<out M : FMatrix>(override val origin: M) : EjmlVector<Float, M>(origin) {
     init {
-        require(origin.numRows == 1) { "The origin matrix must have only one row to form a vector" }
+        require(origin.numCols == 1) { "The origin matrix must have only one column to form a vector" }
     }
 
-    override operator fun get(index: Int): Float = origin[0, index]
+    override operator fun get(index: Int): Float = origin[index, 0]
 }
 
 /**
diff --git a/kmath-ejml/src/jvmTest/kotlin/space/kscience/kmath/ejml/EjmlVectorTest.kt b/kmath-ejml/src/jvmTest/kotlin/space/kscience/kmath/ejml/EjmlVectorTest.kt
index cbc7f7c41..a19a3acc1 100644
--- a/kmath-ejml/src/jvmTest/kotlin/space/kscience/kmath/ejml/EjmlVectorTest.kt
+++ b/kmath-ejml/src/jvmTest/kotlin/space/kscience/kmath/ejml/EjmlVectorTest.kt
@@ -7,6 +7,9 @@ package space.kscience.kmath.ejml
 
 import org.ejml.data.DMatrixRMaj
 import org.ejml.dense.row.RandomMatrices_DDRM
+import space.kscience.kmath.linear.invoke
+import space.kscience.kmath.structures.asBuffer
+import space.kscience.kmath.testutils.assertBufferEquals
 import kotlin.random.Random
 import kotlin.random.asJavaRandom
 import kotlin.test.Test
@@ -54,4 +57,10 @@ internal class EjmlVectorTest {
         val w = EjmlDoubleVector(m)
         assertSame(m, w.origin)
     }
+
+    @Test
+    fun unaryMinus() = EjmlLinearSpaceDDRM {
+        val mu = doubleArrayOf(1.0, 2.0, 3.0).asBuffer()
+        assertBufferEquals(mu, -(-mu))
+    }
 }