diff --git a/float64slices.go b/float64slices.go
index 6626bd5d..5790b32f 100644
--- a/float64slices.go
+++ b/float64slices.go
@@ -1,27 +1,5 @@
 package proj
 
-// ForwardFloat64Slices transforms float64Slices in the forward direction.
-func (pj *PJ) ForwardFloat64Slices(float64Slices [][]float64) error {
-	return pj.TransFloat64Slices(DirectionFwd, float64Slices)
-}
-
-// InverseFloat64Slices transforms float64Slices in the inverse direction.
-func (pj *PJ) InverseFloat64Slices(float64Slices [][]float64) error {
-	return pj.TransFloat64Slices(DirectionInv, float64Slices)
-}
-
-// TransFloat64Slices transforms float64Slices.
-func (pj *PJ) TransFloat64Slices(direction Direction, float64Slices [][]float64) error {
-	coords := Float64SlicesToCoords(float64Slices)
-	if err := pj.TransArray(direction, coords); err != nil {
-		return err
-	}
-	for i, coord := range coords {
-		copy(float64Slices[i], coord[:])
-	}
-	return nil
-}
-
 // CoordsToFloat64Slices is a convenience function that converts a slice of
 // Coords to a slice of []float64s. For performance, the returned []float64s
 // alias coords.
diff --git a/float64slices_test.go b/float64slices_test.go
index 9761f30e..2ef82e3f 100644
--- a/float64slices_test.go
+++ b/float64slices_test.go
@@ -42,69 +42,3 @@ func TestCoordsToFloat64Slices(t *testing.T) {
 		})
 	}
 }
-
-func TestTransFloat64Slices(t *testing.T) {
-	for i, tc := range []struct {
-		float64Slices [][]float64
-		expected      [][]float64
-		delta         float64
-	}{
-		{
-			float64Slices: nil,
-			expected:      nil,
-		},
-		{
-			float64Slices: [][]float64{},
-			expected:      [][]float64{},
-		},
-		{
-			float64Slices: [][]float64{
-				{48.856613, 2.352222, 78},
-				{40.712778, -74.006111, 10},
-			},
-			expected: [][]float64{
-				{261848.15527273554, 6250566.54904563, 78},
-				{-8238322.592110482, 4970068.348185822, 10},
-			},
-			delta: 1e-9,
-		},
-		{
-			float64Slices: [][]float64{
-				{48.856613, 2.352222, 78, 1},
-				{40.712778, -74.006111, 10, 2},
-			},
-			expected: [][]float64{
-				{261848.15527273554, 6250566.54904563, 78, 1},
-				{-8238322.592110482, 4970068.348185822, 10, 2},
-			},
-			delta: 1e-9,
-		},
-		{
-			float64Slices: [][]float64{
-				{48.856613, 2.352222},
-				{40.712778, -74.006111, 10, 2},
-			},
-			expected: [][]float64{
-				{261848.15527273554, 6250566.54904563},
-				{-8238322.592110482, 4970068.348185822, 10, 2},
-			},
-			delta: 1e-9,
-		},
-	} {
-		t.Run(strconv.Itoa(i), func(t *testing.T) {
-			pj, err := proj.NewCRSToCRS("EPSG:4326", "EPSG:3857", nil)
-			assert.NoError(t, err)
-			float64Slices := slices.Clone(tc.float64Slices)
-			assert.NoError(t, pj.ForwardFloat64Slices(float64Slices))
-			assertInDeltaFloat64Slices(t, tc.expected, float64Slices, tc.delta)
-		})
-	}
-}
-
-func assertInDeltaFloat64Slices(tb testing.TB, expected, actual [][]float64, delta float64) {
-	tb.Helper()
-	assert.Equal(tb, len(expected), len(actual))
-	for i := range expected {
-		assertInDeltaFloat64Slice(tb, expected[i], actual[i], delta)
-	}
-}
diff --git a/pj.go b/pj.go
index 442ab2dd..9adbbfab 100644
--- a/pj.go
+++ b/pj.go
@@ -79,6 +79,11 @@ func (pj *PJ) ForwardFloat64Slice(float64Slice []float64) ([]float64, error) {
 	return pj.TransFloat64Slice(DirectionFwd, float64Slice)
 }
 
+// ForwardFloat64Slices transforms float64Slices in the forward direction.
+func (pj *PJ) ForwardFloat64Slices(float64Slices [][]float64) error {
+	return pj.TransFloat64Slices(DirectionFwd, float64Slices)
+}
+
 // Geod returns the distance, forward azimuth, and reverse azimuth between a and b.
 func (pj *PJ) Geod(a, b Coord) (float64, float64, float64) {
 	pj.context.Lock()
@@ -140,6 +145,11 @@ func (pj *PJ) InverseFloat64Slice(float64Slice []float64) ([]float64, error) {
 	return pj.TransFloat64Slice(DirectionInv, float64Slice)
 }
 
+// InverseFloat64Slices transforms float64Slices in the inverse direction.
+func (pj *PJ) InverseFloat64Slices(float64Slices [][]float64) error {
+	return pj.TransFloat64Slices(DirectionInv, float64Slices)
+}
+
 // LPDist returns the geodesic distance between a and b in geodetic coordinates.
 func (pj *PJ) LPDist(a, b Coord) float64 {
 	pj.context.Lock()
@@ -248,6 +258,18 @@ func (pj *PJ) TransFloat64Slice(direction Direction, float64Slice []float64) ([]
 	return float64Slice, nil
 }
 
+// TransFloat64Slices transforms float64Slices.
+func (pj *PJ) TransFloat64Slices(direction Direction, float64Slices [][]float64) error {
+	coords := Float64SlicesToCoords(float64Slices)
+	if err := pj.TransArray(direction, coords); err != nil {
+		return err
+	}
+	for i, coord := range coords {
+		copy(float64Slices[i], coord[:])
+	}
+	return nil
+}
+
 // TransGeneric transforms a series of coordinates.
 func (pj *PJ) TransGeneric(direction Direction, x *float64, sx, nx int, y *float64, sy, ny int, z *float64, sz, nz int, m *float64, sm, nm int) error {
 	pj.context.Lock()
diff --git a/pj_test.go b/pj_test.go
index f20dbadb..c3e233b5 100644
--- a/pj_test.go
+++ b/pj_test.go
@@ -542,6 +542,64 @@ func TestPJ_NormalizeForVisualizationForEastingNorthingCRS(t *testing.T) {
 	assertInDeltaFloat64Slice(t, newYorkEPSG3857[:], actualCoord[:], 1e-7)
 }
 
+func TestPJ_TransFloat64Slices(t *testing.T) {
+	for i, tc := range []struct {
+		float64Slices [][]float64
+		expected      [][]float64
+		delta         float64
+	}{
+		{
+			float64Slices: nil,
+			expected:      nil,
+		},
+		{
+			float64Slices: [][]float64{},
+			expected:      [][]float64{},
+		},
+		{
+			float64Slices: [][]float64{
+				{48.856613, 2.352222, 78},
+				{40.712778, -74.006111, 10},
+			},
+			expected: [][]float64{
+				{261848.15527273554, 6250566.54904563, 78},
+				{-8238322.592110482, 4970068.348185822, 10},
+			},
+			delta: 1e-9,
+		},
+		{
+			float64Slices: [][]float64{
+				{48.856613, 2.352222, 78, 1},
+				{40.712778, -74.006111, 10, 2},
+			},
+			expected: [][]float64{
+				{261848.15527273554, 6250566.54904563, 78, 1},
+				{-8238322.592110482, 4970068.348185822, 10, 2},
+			},
+			delta: 1e-9,
+		},
+		{
+			float64Slices: [][]float64{
+				{48.856613, 2.352222},
+				{40.712778, -74.006111, 10, 2},
+			},
+			expected: [][]float64{
+				{261848.15527273554, 6250566.54904563},
+				{-8238322.592110482, 4970068.348185822, 10, 2},
+			},
+			delta: 1e-9,
+		},
+	} {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			pj, err := proj.NewCRSToCRS("EPSG:4326", "EPSG:3857", nil)
+			assert.NoError(t, err)
+			float64Slices := slices.Clone(tc.float64Slices)
+			assert.NoError(t, pj.ForwardFloat64Slices(float64Slices))
+			assertInDeltaFloat64Slices(t, tc.expected, float64Slices, tc.delta)
+		})
+	}
+}
+
 func assertInDelta(tb testing.TB, expected, actual, delta float64) {
 	tb.Helper()
 	if actualDelta := math.Abs(expected - actual); actualDelta > delta {
@@ -558,3 +616,11 @@ func assertInDeltaFloat64Slice(tb testing.TB, expected, actual []float64, delta
 		}
 	}
 }
+
+func assertInDeltaFloat64Slices(tb testing.TB, expected, actual [][]float64, delta float64) {
+	tb.Helper()
+	assert.Equal(tb, len(expected), len(actual))
+	for i := range expected {
+		assertInDeltaFloat64Slice(tb, expected[i], actual[i], delta)
+	}
+}