big: added a few missing functions:
- sign to determine if a value is < 0, == 0, > 0
- abs to compute absolute value
- Rat.IsInt to test if a rational number is representable as an integer
R=rsc
CC=golang-dev
https://golang.org/cl/1761042
diff --git a/src/pkg/big/int_test.go b/src/pkg/big/int_test.go
index 82b5417..66379ca 100755
--- a/src/pkg/big/int_test.go
+++ b/src/pkg/big/int_test.go
@@ -47,6 +47,18 @@
}
+func TestSignZ(t *testing.T) {
+ var zero Int
+ for _, a := range sumZZ {
+ s := a.z.Sign()
+ e := a.z.Cmp(&zero)
+ if s != e {
+ t.Errorf("got %d; want %d for z = %v", s, e, a.z)
+ }
+ }
+}
+
+
func TestSetZ(t *testing.T) {
for _, a := range sumZZ {
var z Int
@@ -61,6 +73,23 @@
}
+func TestAbsZ(t *testing.T) {
+ var zero Int
+ for _, a := range sumZZ {
+ var z Int
+ z.Abs(a.z)
+ var e Int
+ e.Set(a.z)
+ if e.Cmp(&zero) < 0 {
+ e.Sub(&zero, &e)
+ }
+ if z.Cmp(&e) != 0 {
+ t.Errorf("got z = %v; want %v", z, e)
+ }
+ }
+}
+
+
func testFunZZ(t *testing.T, msg string, f funZZ, a argZZ) {
var z Int
f(&z, a.x, a.y)
