ref #65, new formula function: TIME

calc.go

@@ -489,6 +489,7 @@ type formulaFuncs struct {
 //    T
 //    TAN
 //    TANH
+//    TIME
 //    TODAY
 //    TRANSPOSE
 //    TRIM
@@ -6848,6 +6849,30 @@ func (fn *formulaFuncs) NOW(argsList *list.List) formulaArg {
 	return newNumberFormulaArg(25569.0 + float64(now.Unix()+int64(offset))/86400)
 }
 
+// TIME function accepts three integer arguments representing hours, minutes
+// and seconds, and returns an Excel time. I.e. the function returns the
+// decimal value that represents the time in Excel. The syntax of the Time
+// function is:
+//
+//    TIME(hour,minute,second)
+//
+func (fn *formulaFuncs) TIME(argsList *list.List) formulaArg {
+	if argsList.Len() != 3 {
+		return newErrorFormulaArg(formulaErrorVALUE, "TIME requires 3 number arguments")
+	}
+	h := argsList.Front().Value.(formulaArg).ToNumber()
+	m := argsList.Front().Next().Value.(formulaArg).ToNumber()
+	s := argsList.Back().Value.(formulaArg).ToNumber()
+	if h.Type != ArgNumber || m.Type != ArgNumber || s.Type != ArgNumber {
+		return newErrorFormulaArg(formulaErrorVALUE, "TIME requires 3 number arguments")
+	}
+	t := (h.Number*3600 + m.Number*60 + s.Number) / 86400
+	if t < 0 {
+		return newErrorFormulaArg(formulaErrorNUM, formulaErrorNUM)
+	}
+	return newNumberFormulaArg(t)
+}
+
 // TODAY function returns the current date. The function has no arguments and
 // therefore. The syntax of the function is:
 //

calc_test.go

@@ -1016,6 +1016,10 @@ func TestCalcCellValue(t *testing.T) {
 		"=YEARFRAC(\"02/29/2000\", \"01/29/2001\",1)": "0.915300546448087",
 		"=YEARFRAC(\"02/29/2000\", \"03/29/2000\",1)": "0.0792349726775956",
 		"=YEARFRAC(\"01/31/2000\", \"03/29/2000\",4)": "0.163888888888889",
+		// TIME
+		"=TIME(5,44,32)":             "0.239259259259259",
+		"=TIME(\"5\",\"44\",\"32\")": "0.239259259259259",
+		"=TIME(0,0,73)":              "0.000844907407407407",
 		// Text Functions
 		// CHAR
 		"=CHAR(65)": "A",
@@ -2093,6 +2097,10 @@ func TestCalcCellValue(t *testing.T) {
 		"=YEARFRAC(42005,42094,\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
 		// NOW
 		"=NOW(A1)": "NOW accepts no arguments",
+		// TIME
+		"=TIME()":         "TIME requires 3 number arguments",
+		"=TIME(\"\",0,0)": "TIME requires 3 number arguments",
+		"=TIME(0,0,-1)":   "#NUM!",
 		// TODAY
 		"=TODAY(A1)": "TODAY accepts no arguments",
 		// Text Functions