func ExampleDistanceMatrix_NonNegative() { d1 := cluster.DistanceMatrix{ {0, -1}, // false {-1, 0}, } d2 := cluster.DistanceMatrix{ {0}, // true {1, 2}, } d3 := cluster.DistanceMatrix{} // true (no negatives present) d4 := cluster.DistanceMatrix{ {0, math.NaN()}, // true {3, 0}, } fmt.Println(d1.NonNegative()) fmt.Println(d2.NonNegative()) fmt.Println(d3.NonNegative()) fmt.Println(d4.NonNegative()) // Outpupt: // false // true // true // true }