mostly working

timeutil.go

@@ -80,6 +80,11 @@ func TimeToFloat64(t time.Time) float64 {
 	return float64(t.UnixNano())
 }
 
+// TimeFromFloat64 returns a time from a float64.
+func TimeFromFloat64(tf float64) time.Time {
+	return time.Unix(0, int64(tf))
+}
+
 // TimeDescending sorts a given list of times ascending, or min to max.
 type TimeDescending []time.Time
 
@@ -103,3 +108,43 @@ func (a TimeAscending) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
 
 // Less implements sort.Sorter
 func (a TimeAscending) Less(i, j int) bool { return a[i].Before(a[j]) }
+
+// Days generates a seq of timestamps by day, from -days to today.
+func Days(days int) []time.Time {
+	var values []time.Time
+	for day := days; day >= 0; day-- {
+		values = append(values, time.Now().AddDate(0, 0, -day))
+	}
+	return values
+}
+
+// Hours returns a sequence of times by the hour for a given number of hours
+// after a given start.
+func Hours(start time.Time, totalHours int) []time.Time {
+	times := make([]time.Time, totalHours)
+
+	last := start
+	for i := 0; i < totalHours; i++ {
+		times[i] = last
+		last = last.Add(time.Hour)
+	}
+
+	return times
+}
+
+// HoursFilled adds zero values for the data bounded by the start and end of the xdata array.
+func HoursFilled(xdata []time.Time, ydata []float64) ([]time.Time, []float64) {
+	start, end := TimeMinMax(xdata...)
+	totalHours := DiffHours(start, end)
+
+	finalTimes := Hours(start, totalHours+1)
+	finalValues := make([]float64, totalHours+1)
+
+	var hoursFromStart int
+	for i, xd := range xdata {
+		hoursFromStart = DiffHours(start, xd)
+		finalValues[hoursFromStart] = ydata[i]
+	}
+
+	return finalTimes, finalValues
+}