From 620f873186e9f69a05d88f79cfb899b42e584331 Mon Sep 17 00:00:00 2001
From: xuri <xuri.me@gmail.com>
Date: Mon, 18 Oct 2021 00:18:56 +0800
Subject: [PATCH] ref #65: new formula function AMORLINC

---
 calc.go      | 35 +++++++++++++++++++++++++++++++++++
 calc_test.go | 21 +++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/calc.go b/calc.go
index d63bb3f..ba9085e 100644
--- a/calc.go
+++ b/calc.go
@@ -267,6 +267,7 @@ type formulaFuncs struct {
 //    ACOT
 //    ACOTH
 //    AMORDEGRC
+//    AMORLINC
 //    AND
 //    ARABIC
 //    ASIN
@@ -8459,6 +8460,40 @@ func (fn *formulaFuncs) AMORDEGRC(argsList *list.List) formulaArg {
 	return newNumberFormulaArg(nRate)
 }
 
+// AMORLINC function is provided for users of the French accounting system.
+// The function calculates the prorated linear depreciation of an asset for a
+// specified accounting period. The syntax of the function is:
+//
+//    AMORLINC(cost,date_purchased,first_period,salvage,period,rate,[basis])
+//
+func (fn *formulaFuncs) AMORLINC(argsList *list.List) formulaArg {
+	if argsList.Len() != 6 && argsList.Len() != 7 {
+		return newErrorFormulaArg(formulaErrorVALUE, "AMORLINC requires 6 or 7 arguments")
+	}
+	args := fn.prepareAmorArgs("AMORLINC", argsList)
+	if args.Type != ArgList {
+		return args
+	}
+	cost, datePurchased, firstPeriod, salvage, period, rate, basis := args.List[0], args.List[1], args.List[2], args.List[3], args.List[4], args.List[5], args.List[6]
+	frac := yearFrac(datePurchased.Number, firstPeriod.Number, int(basis.Number))
+	if frac.Type != ArgNumber {
+		return frac
+	}
+	rate1 := frac.Number * cost.Number * rate.Number
+	if period.Number == 0 {
+		return newNumberFormulaArg(rate1)
+	}
+	rate2 := cost.Number * rate.Number
+	delta := cost.Number - salvage.Number
+	periods := int((delta - rate1) / rate2)
+	if int(period.Number) <= periods {
+		return newNumberFormulaArg(rate2)
+	} else if int(period.Number)-1 == periods {
+		return newNumberFormulaArg(delta - rate2*float64(periods) - rate1)
+	}
+	return newNumberFormulaArg(0)
+}
+
 // CUMIPMT function calculates the cumulative interest paid on a loan or
 // investment, between two specified periods. The syntax of the function is:
 //
diff --git a/calc_test.go b/calc_test.go
index 6d16ce9..abf6afa 100644
--- a/calc_test.go
+++ b/calc_test.go
@@ -1242,6 +1242,12 @@ func TestCalcCellValue(t *testing.T) {
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",20,1,25%,4)":  "41",
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",109,1,25%,4)": "54",
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",110,2,25%,4)": "0",
+		// AMORLINC
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,20%,4)":  "30",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,0%,4)":   "0",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,20,15%,4)": "0",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,6,15%,4)":  "0.6875",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,0,15%,4)":  "16.8125",
 		// CUMIPMT
 		"=CUMIPMT(0.05/12,60,50000,1,12,0)":  "-2294.97753732664",
 		"=CUMIPMT(0.05/12,60,50000,13,24,0)": "-1833.1000665738893",
@@ -2327,6 +2333,21 @@ func TestCalcCellValue(t *testing.T) {
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",20,1,20%,\"\")": "#NUM!",
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",20,1,50%)":      "AMORDEGRC requires rate to be < 0.5",
 		"=AMORDEGRC(150,\"01/01/2015\",\"09/30/2015\",20,1,20%,5)":    "invalid basis",
+		// AMORLINC
+		"=AMORLINC()": "AMORLINC requires 6 or 7 arguments",
+		"=AMORLINC(\"\",\"01/01/2015\",\"09/30/2015\",20,1,20%)":     "AMORLINC requires cost to be number argument",
+		"=AMORLINC(-1,\"01/01/2015\",\"09/30/2015\",20,1,20%)":       "AMORLINC requires cost >= 0",
+		"=AMORLINC(150,\"\",\"09/30/2015\",20,1,20%)":                "#VALUE!",
+		"=AMORLINC(150,\"01/01/2015\",\"\",20,1,20%)":                "#VALUE!",
+		"=AMORLINC(150,\"09/30/2015\",\"01/01/2015\",20,1,20%)":      "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",\"\",1,20%)":    "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",-1,1,20%)":      "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,\"\",20%)":   "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,-1,20%)":     "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,\"\")":     "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,-1)":       "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,20%,\"\")": "#NUM!",
+		"=AMORLINC(150,\"01/01/2015\",\"09/30/2015\",20,1,20%,5)":    "invalid basis",
 		// CUMIPMT
 		"=CUMIPMT()":               "CUMIPMT requires 6 arguments",
 		"=CUMIPMT(0,0,0,0,0,2)":    "#N/A",