/// <summary>
/// LaTeX的な数式を普通の数式に変換
/// </summary>
/// <param name="s"></param>
/// <returns></returns>
public static string LaTeXtoFormula(string s)
{
if (s.Contains("{"))
{
for (int i = 0; i < s.Length; i++)
{
if (s[i] == '~')
{
var LaTeXFuncName = Regex.Replace(s.Substring(i), "^~(\\w+)\\{.*$", "$1");
switch (LaTeXFuncName)
{
case "frac":
var Numor = OperateBrackets.TakeoutInsideofBracket(s.Substring(i + LaTeXFuncName.Length + 1), 0, "{}");
var Denor = OperateBrackets.TakeoutInsideofBracket(s.Substring(i + LaTeXFuncName.Length + 1 + Numor.Length + 2), 0, "{}");
s = s.Remove(i, 9 + Numor.Length + Denor.Length);
s = s.Insert(i, "(" + LaTeXtoFormula(Numor) + ")/(" + LaTeXtoFormula(Denor) + ")");
break;
case "root":
var rootindx = OperateBrackets.TakeoutInsideofBracket(s.Substring(i + LaTeXFuncName.Length + 1), 0, "{}");
var radicant = OperateBrackets.TakeoutInsideofBracket(s.Substring(i + LaTeXFuncName.Length + 1 + rootindx.Length + 2), 0, "{}");
s = s.Remove(i, 9 + rootindx.Length + radicant.Length);
s = s.Insert(i, "#$root$#(" + LaTeXtoFormula(rootindx) + "," + LaTeXtoFormula(radicant) + ")");
break;
default:
var parameters = new List <string>();
var searchingindex = 0;
while (true)
{
var inside = OperateBrackets.TakeoutInsideofBracket(s.Substring(LaTeXFuncName.Length + 1 + i), searchingindex, "{}");
parameters.Add(inside);
searchingindex += inside.Length + 2;
if (s.Length <= searchingindex + LaTeXFuncName.Length + 1 ||
(s.Length > searchingindex + LaTeXFuncName.Length + 1 && s[searchingindex + LaTeXFuncName.Length + 1] != '{'))
{
break;
}
}
s = s.Remove(i, LaTeXFuncName.Length + 1 + searchingindex);
s = s.Insert(i, "#$" + LaTeXFuncName + "$#(" + string.Join(",", parameters) + ")");
break;
}
}
else if (s[i] == '^' && i + 1 < s.Length && s[i + 1] == '{')
{
var content = OperateBrackets.TakeoutInsideofBracket(s.Substring(i + 1), 0, "{}");
s = s.Remove(i, 3 + content.Length);
s = s.Insert(i, "^(" + LaTeXtoFormula(content) + ")");
}
}
}
return(s);
}
/// <summary>
/// 文字式(未整理)の累乗を処理
/// </summary>
/// <param name="f"></param>
/// <returns></returns>
public static async Task <string> ExpandPowAsync(string f)
{
if (f.Contains("^"))
{
f = Regex.Replace(f, "^\\^(\\+|-)?(\\d|\\.)*", ""); //頭の累乗記号＋数字は消す
f = Regex.Replace(f, "\\^$", ""); //末尾の累乗記号も消す
f = Regex.Replace(f, "\\^([a-z|A-Z])", "$1"); //文字で累乗されている場合は累乗をなかったことにする
f = Regex.Replace(f, "[a-z|A-Z]\\^(\\d)+", Match =>
{
return(new string(Match.Value.First(), int.Parse(Regex.Replace(Match.Value, "(.*)(\\d+)(.*)", "$2"))));
});
while (f.Contains("^"))
{
int PowIndex = f.IndexOf('^');
if (PowIndex == 0)
{
throw new Exception(AppResources.PowerMustTop);
}
string Powed = "1";
if (f[PowIndex - 1] == ')')
{
//Xamarin.Forms.DependencyService.Get<IToastService>()
//.Show("括弧に'^'は付けられません");
Powed = "(" + OperateBrackets.TakeoutInsideofBracket(f, PowIndex - 2) + ")";
throw new Exception(AppResources.CantAddPowerAfterParenthes);
}
else if (Regex.IsMatch(f[PowIndex - 1].ToString(), "(\\+|-)?(\\d|\\.)"))
{
Powed = Regex.Match(f.Substring(0, PowIndex), "(\\+|-)?(\\d+|\\.)$").Value;
}
else
{
Powed = f[PowIndex - 1].ToString();
}
Double Powist = 1.0;
if (f[PowIndex + 1] == '(')
{
var content = OperateBrackets.TakeoutInsideofBracket(f, PowIndex + 1);
if (Regex.IsMatch(content, "[a-z]"))
{
throw new Exception(AppResources.CantAddPowerAfterChar);
}
Powist = await SolveNumFormulas.SolveNumFormula(content);
f = f.Remove(PowIndex - 1, content.Length + 4);//^の分(1)+カッコの分(2)+
}
else
{
var content = Regex.Match(f.Substring(PowIndex), "^(\\+|-)?(\\d|\\.)+").Value;
Powist = double.Parse(content);
f = f.Remove(PowIndex - 1, content.Length + 2);
}
var repeated = "";
if (double.TryParse(Powed, out double Poweddouble))
{
repeated = Math.Pow(Poweddouble, Powist).ToString();
}
else
{
repeated = string.Concat(Enumerable.Repeat(Powed, (int)Powist));
}
f = f.Insert(PowIndex - 1, repeated);
}
}
return(f);
}
