all: fix some comments (#161)

fix some comments

Signed-off-by: cuishuang <imcusg@gmail.com>

Author: cuishuang

s2/builder_snapper.go

@@ -348,7 +348,7 @@ func (sf CellIDSnapper) SnapPoint(point Point) Point {
 }
 
 const (
-	// The minum exponent supported for snapping.
+	// The minimum exponent supported for snapping.
 	minIntSnappingExponent = 0
 	// The maximum exponent supported for snapping.
 	maxIntSnappingExponent = 10

s2/cell.go

@@ -124,7 +124,7 @@ func (c Cell) VertexRaw(k int) Point {
 	return Point{faceUVToXYZ(int(c.face), c.uv.Vertices()[k].X, c.uv.Vertices()[k].Y)}
 }
 
-// Edge returns the nomalized inward-facing normal of the great circle passing through
+// Edge returns the normalized inward-facing normal of the great circle passing through
 // the CCW ordered edge from vertex k to vertex k+1 (mod 4) (for k = 0,1,2,3)
 func (c Cell) Edge(k int) Point {
 	return Point{c.EdgeRaw(k).Normalize()}

s2/edge_crossings.go

@@ -367,7 +367,7 @@ func intersectionStableSorted(a0, a1, b0, b1 Point) (Point, bool) {
 // is not guaranteed to have the correct sign (i.e., the return value may need
 // to be negated).
 func intersectionExact(a0, a1, b0, b1 Point) Point {
-	// Since we are using presice arithmetic, we don't need to worry about
+	// Since we are using precise arithmetic, we don't need to worry about
 	// numerical stability.
 	a0P := r3.PreciseVectorFromVector(a0.Vector)
 	a1P := r3.PreciseVectorFromVector(a1.Vector)

s2/lexicon.go

@@ -149,7 +149,7 @@ func (l *sequenceLexicon) size() int {
 	return len(l.begins) - 1
 }
 
-// hash returns a hash of this sequence of int32s.
+// hashSet returns a hash of this sequence of int32s.
 func hashSet(s []int32) uint32 {
 	// TODO(roberts): We just need a way to nicely hash all the values down to
 	// a 32-bit value. To ensure no unnecessary dependencies we use the core

s2/pointcompression.go

@@ -300,7 +300,7 @@ func stToPiQi(s float64, level uint) uint32 {
 	return uint32(s * float64(int(1)<<level))
 }
 
-// siTiToPiQi returns the value transformed into the PiQi coordinate spade.
+// siTitoPiQi returns the value transformed into the PiQi coordinate spade.
 // encodeFirstPointFixedLength encodes the return value using level bits,
 // so we clamp si to the range [0, 2**level - 1] before trying to encode
 // it. This is okay because if si == maxSiTi, then it is not a cell center

s2/polyline_alignment.go

@@ -97,7 +97,7 @@ type columnStride struct {
 	end   int
 }
 
-// inRange reports if the given index is in range of this stride.
+// InRange reports if the given index is in range of this stride.
 func (c columnStride) InRange(index int) bool {
 	return c.start <= index && index < c.end
 }
@@ -235,7 +235,7 @@ func (w *window) checkedColumnStride(row int) columnStride {
 	return w.strides[row]
 }
 
-// upscale returns a new, larger window that is an upscaled version of this window.
+// upsample returns a new, larger window that is an upscaled version of this window.
 //
 // Used by ApproximateAlignment window expansion step.
 func (w *window) upsample(newRows, newCols int) *window {
@@ -402,7 +402,7 @@ func ExactVertexAlignmentCost(a, b *Polyline) float64 {
 	return cost[len(cost)-1]
 }
 
-// GetExactVertexAlignment takes two non-empty polylines as input, and returns
+// ExactVertexAlignment takes two non-empty polylines as input, and returns
 // the VertexAlignment corresponding to the optimal alignment between them. This
 // method is quadratic O(A*B) in both space and time complexity.
 func ExactVertexAlignment(a, b *Polyline) *vertexAlignment {

s2/polyline_alignment_test.go

@@ -448,4 +448,4 @@ func TestPolylineAlignmentExactAlignmentCost(t *testing.T) {
 
 // TODO()rsned): Differences from C++
 // Medoid tests
-// Consensus testss
+// Consensus tests

s2/polyline_test.go

@@ -33,7 +33,7 @@ func TestPolylineBasics(t *testing.T) {
 	}
 	empty.Reverse()
 	if len(empty) != 0 {
-		t.Errorf("reveresed empty Polyline should have no vertices")
+		t.Errorf("reversed empty Polyline should have no vertices")
 	}
 
 	latlngs := []LatLng{

s2/predicates.go

@@ -123,7 +123,7 @@ func precSub(a, b *big.Float) *big.Float {
 	return new(big.Float).SetPrec(big.MaxPrec).Sub(a, b)
 }
 
-// precSub is a helper to wrap the boilerplate of multiplying two big.Floats.
+// precMul is a helper to wrap the boilerplate of multiplying two big.Floats.
 func precMul(a, b *big.Float) *big.Float {
 	return new(big.Float).SetPrec(big.MaxPrec).Mul(a, b)
 }

s2/predicates_test.go

@@ -886,7 +886,7 @@ func testCompareDistancesConsistency(t *testing.T, x, a, b Point, distFunc compa
 }
 
 // choosePointNearPlaneOrAxes returns a random Point that is often near the
-// intersection of one of the coodinates planes or coordinate axes with the unit
+// intersection of one of the coordinates planes or coordinate axes with the unit
 // sphere. (It is possible to represent very small perturbations near such points.)
 func choosePointNearPlaneOrAxes() Point {
 	p := randomPoint()
@@ -1042,7 +1042,7 @@ func TestPredicatesSignDotProd(t *testing.T) {
 	for _, test := range tests {
 		got := SignDotProd(test.a, test.b)
 		if got != test.want {
-			t.Errorf("SignDotProd(%+v, %+v) = %d, wnat %d", test.a, test.b, got, test.want)
+			t.Errorf("SignDotProd(%+v, %+v) = %d, want %d", test.a, test.b, got, test.want)
 		}
 
 		gotPrec := "EXACT"