mirror of
https://github.com/prometheus/prometheus.git
synced 2024-12-26 14:09:41 -08:00
a1af3c27d4
To avoid a circular reference between promql and promqltest. Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
42 lines
1.3 KiB
Go
42 lines
1.3 KiB
Go
// Copyright 2024 The Prometheus Authors
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package almost
|
|
|
|
import "math"
|
|
|
|
var minNormal = math.Float64frombits(0x0010000000000000) // The smallest positive normal value of type float64.
|
|
|
|
// Equal returns true if a and b differ by less than their sum
|
|
// multiplied by epsilon.
|
|
func Equal(a, b, epsilon float64) bool {
|
|
// NaN has no equality but for testing we still want to know whether both values
|
|
// are NaN.
|
|
if math.IsNaN(a) && math.IsNaN(b) {
|
|
return true
|
|
}
|
|
|
|
// Cf. http://floating-point-gui.de/errors/comparison/
|
|
if a == b {
|
|
return true
|
|
}
|
|
|
|
absSum := math.Abs(a) + math.Abs(b)
|
|
diff := math.Abs(a - b)
|
|
|
|
if a == 0 || b == 0 || absSum < minNormal {
|
|
return diff < epsilon*minNormal
|
|
}
|
|
return diff/math.Min(absSum, math.MaxFloat64) < epsilon
|
|
}
|