#65 fn: BESSELK and BESSELY

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xuri 2021-05-09 14:20:17 +08:00
parent 0e0237e62d
commit 423bc26d1f
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2 changed files with 187 additions and 0 deletions

165
calc.go
View File

@ -232,6 +232,8 @@ var tokenPriority = map[string]int{
// BASE
// BESSELI
// BESSELJ
// BESSELK
// BESSELY
// BIN2DEC
// BIN2HEX
// BIN2OCT
@ -1334,6 +1336,169 @@ func (fn *formulaFuncs) bassel(argsList *list.List, modfied bool) formulaArg {
return newNumberFormulaArg(result)
}
// BESSELK function calculates the modified Bessel functions, Kn(x), which are
// also known as the hyperbolic Bessel Functions. These are the equivalent of
// the Bessel functions, evaluated for purely imaginary arguments. The syntax
// of the function is:
//
// BESSELK(x,n)
//
func (fn *formulaFuncs) BESSELK(argsList *list.List) formulaArg {
if argsList.Len() != 2 {
return newErrorFormulaArg(formulaErrorVALUE, "BESSELK requires 2 numeric arguments")
}
x, n := argsList.Front().Value.(formulaArg).ToNumber(), argsList.Back().Value.(formulaArg).ToNumber()
if x.Type != ArgNumber {
return x
}
if n.Type != ArgNumber {
return n
}
if x.Number <= 0 || n.Number < 0 {
return newErrorFormulaArg(formulaErrorNUM, formulaErrorNUM)
}
var result float64
switch math.Floor(n.Number) {
case 0:
result = fn.besselK0(x)
case 1:
result = fn.besselK1(x)
default:
result = fn.besselK2(x, n)
}
return newNumberFormulaArg(result)
}
// besselK0 is an implementation of the formula function BESSELK.
func (fn *formulaFuncs) besselK0(x formulaArg) float64 {
var y float64
if x.Number <= 2 {
n2 := x.Number * 0.5
y = n2 * n2
args := list.New()
args.PushBack(x)
args.PushBack(newNumberFormulaArg(0))
return -math.Log(n2)*fn.BESSELI(args).Number +
(-0.57721566 + y*(0.42278420+y*(0.23069756+y*(0.3488590e-1+y*(0.262698e-2+y*
(0.10750e-3+y*0.74e-5))))))
}
y = 2 / x.Number
return math.Exp(-x.Number) / math.Sqrt(x.Number) *
(1.25331414 + y*(-0.7832358e-1+y*(0.2189568e-1+y*(-0.1062446e-1+y*
(0.587872e-2+y*(-0.251540e-2+y*0.53208e-3))))))
}
// besselK1 is an implementation of the formula function BESSELK.
func (fn *formulaFuncs) besselK1(x formulaArg) float64 {
var n2, y float64
if x.Number <= 2 {
n2 = x.Number * 0.5
y = n2 * n2
args := list.New()
args.PushBack(x)
args.PushBack(newNumberFormulaArg(1))
return math.Log(n2)*fn.BESSELI(args).Number +
(1+y*(0.15443144+y*(-0.67278579+y*(-0.18156897+y*(-0.1919402e-1+y*(-0.110404e-2+y*(-0.4686e-4)))))))/x.Number
}
y = 2 / x.Number
return math.Exp(-x.Number) / math.Sqrt(x.Number) *
(1.25331414 + y*(0.23498619+y*(-0.3655620e-1+y*(0.1504268e-1+y*(-0.780353e-2+y*
(0.325614e-2+y*(-0.68245e-3)))))))
}
// besselK2 is an implementation of the formula function BESSELK.
func (fn *formulaFuncs) besselK2(x, n formulaArg) float64 {
tox, bkm, bk, bkp := 2/x.Number, fn.besselK0(x), fn.besselK1(x), 0.0
for i := 1.0; i < n.Number; i++ {
bkp = bkm + i*tox*bk
bkm = bk
bk = bkp
}
return bk
}
// BESSELY function returns the Bessel function, Yn(x), (also known as the
// Weber function or the Neumann function), for a specified order and value
// of x. The syntax of the function is:
//
// BESSELY(x,n)
//
func (fn *formulaFuncs) BESSELY(argsList *list.List) formulaArg {
if argsList.Len() != 2 {
return newErrorFormulaArg(formulaErrorVALUE, "BESSELY requires 2 numeric arguments")
}
x, n := argsList.Front().Value.(formulaArg).ToNumber(), argsList.Back().Value.(formulaArg).ToNumber()
if x.Type != ArgNumber {
return x
}
if n.Type != ArgNumber {
return n
}
if x.Number <= 0 || n.Number < 0 {
return newErrorFormulaArg(formulaErrorNUM, formulaErrorNUM)
}
var result float64
switch math.Floor(n.Number) {
case 0:
result = fn.besselY0(x)
case 1:
result = fn.besselY1(x)
default:
result = fn.besselY2(x, n)
}
return newNumberFormulaArg(result)
}
// besselY0 is an implementation of the formula function BESSELY.
func (fn *formulaFuncs) besselY0(x formulaArg) float64 {
var y float64
if x.Number < 8 {
y = x.Number * x.Number
f1 := -2957821389.0 + y*(7062834065.0+y*(-512359803.6+y*(10879881.29+y*
(-86327.92757+y*228.4622733))))
f2 := 40076544269.0 + y*(745249964.8+y*(7189466.438+y*
(47447.26470+y*(226.1030244+y))))
args := list.New()
args.PushBack(x)
args.PushBack(newNumberFormulaArg(0))
return f1/f2 + 0.636619772*fn.BESSELJ(args).Number*math.Log(x.Number)
}
z := 8.0 / x.Number
y = z * z
xx := x.Number - 0.785398164
f1 := 1 + y*(-0.1098628627e-2+y*(0.2734510407e-4+y*(-0.2073370639e-5+y*0.2093887211e-6)))
f2 := -0.1562499995e-1 + y*(0.1430488765e-3+y*(-0.6911147651e-5+y*(0.7621095161e-6+y*
(-0.934945152e-7))))
return math.Sqrt(0.636619772/x.Number) * (math.Sin(xx)*f1 + z*math.Cos(xx)*f2)
}
// besselY1 is an implementation of the formula function BESSELY.
func (fn *formulaFuncs) besselY1(x formulaArg) float64 {
if x.Number < 8 {
y := x.Number * x.Number
f1 := x.Number * (-0.4900604943e13 + y*(0.1275274390e13+y*(-0.5153438139e11+y*
(0.7349264551e9+y*(-0.4237922726e7+y*0.8511937935e4)))))
f2 := 0.2499580570e14 + y*(0.4244419664e12+y*(0.3733650367e10+y*(0.2245904002e8+y*
(0.1020426050e6+y*(0.3549632885e3+y)))))
args := list.New()
args.PushBack(x)
args.PushBack(newNumberFormulaArg(1))
return f1/f2 + 0.636619772*(fn.BESSELJ(args).Number*math.Log(x.Number)-1/x.Number)
}
return math.Sqrt(0.636619772/x.Number) * math.Sin(x.Number-2.356194491)
}
// besselY2 is an implementation of the formula function BESSELY.
func (fn *formulaFuncs) besselY2(x, n formulaArg) float64 {
tox, bym, by, byp := 2/x.Number, fn.besselY0(x), fn.besselY1(x), 0.0
for i := 1.0; i < n.Number; i++ {
byp = i*tox*by - bym
bym = by
by = byp
}
return by
}
// BIN2DEC function converts a Binary (a base-2 number) into a decimal number.
// The syntax of the function is:
//

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@ -52,6 +52,16 @@ func TestCalcCellValue(t *testing.T) {
"=BESSELI(32,1)": "5.502845511211247e+12",
// BESSELJ
"=BESSELJ(1.9,2)": "0.329925727692387",
// BESSELK
"=BESSELK(0.05,0)": "3.114234034289662",
"=BESSELK(0.05,1)": "19.90967432724863",
"=BESSELK(0.05,2)": "799.501207124235",
"=BESSELK(3,2)": "0.061510458561912",
// BESSELY
"=BESSELY(0.05,0)": "-1.979311006841528",
"=BESSELY(0.05,1)": "-12.789855163794034",
"=BESSELY(0.05,2)": "-509.61489554491976",
"=BESSELY(9,2)": "-0.229082087487741",
// BIN2DEC
"=BIN2DEC(\"10\")": "2",
"=BIN2DEC(\"11\")": "3",
@ -1208,6 +1218,18 @@ func TestCalcCellValue(t *testing.T) {
"=BESSELJ()": "BESSELJ requires 2 numeric arguments",
"=BESSELJ(\"\",0)": "strconv.ParseFloat: parsing \"\": invalid syntax",
"=BESSELJ(0,\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
// BESSELK
"=BESSELK()": "BESSELK requires 2 numeric arguments",
"=BESSELK(\"\",0)": "strconv.ParseFloat: parsing \"\": invalid syntax",
"=BESSELK(0,\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
"=BESSELK(-1,0)": "#NUM!",
"=BESSELK(1,-1)": "#NUM!",
// BESSELY
"=BESSELY()": "BESSELY requires 2 numeric arguments",
"=BESSELY(\"\",0)": "strconv.ParseFloat: parsing \"\": invalid syntax",
"=BESSELY(0,\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
"=BESSELY(-1,0)": "#NUM!",
"=BESSELY(1,-1)": "#NUM!",
// BIN2DEC
"=BIN2DEC()": "BIN2DEC requires 1 numeric argument",
"=BIN2DEC(\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",