calculator/src/CalcManager/NumberFormattingUtils.cpp

85 lines
2.4 KiB
C++

#include "pch.h"
#include "NumberFormattingUtils.h"
using namespace std;
namespace CalcManager::NumberFormattingUtils
{
/// <summary>
/// Trims out any trailing zeros or decimals in the given input string
/// </summary>
/// <param name="number">number to trim</param>
void TrimTrailingZeros(_Inout_ wstring& number)
{
if (number.find(L'.') == wstring::npos)
{
return;
}
wstring::iterator iter;
for (iter = number.end() - 1;; iter--)
{
if (*iter != L'0')
{
number.erase(iter + 1, number.end());
break;
}
}
if (*(number.end() - 1) == L'.')
{
number.erase(number.end() - 1, number.end());
}
}
/// <summary>
/// Get number of digits (whole number part + decimal part)</summary>
/// <param name="value">the number</param>
unsigned int GetNumberDigits(wstring value)
{
TrimTrailingZeros(value);
unsigned int numberSignificantDigits = static_cast<unsigned int>(value.size());
if (value.find(L'.') != wstring::npos)
{
--numberSignificantDigits;
}
if (value.find(L'-') != wstring::npos)
{
--numberSignificantDigits;
}
return numberSignificantDigits;
}
/// <summary>
/// Get number of digits (whole number part only)</summary>
/// <param name="value">the number</param>
unsigned int GetNumberDigitsWholeNumberPart(double value)
{
return value == 0 ? 1 : (1 + (int)log10(abs(value)));
}
/// <summary>
/// Rounds the given double to the given number of significant digits
/// </summary>
/// <param name="num">input double</param>
/// <param name="numSignificant">int number of significant digits to round to</param>
wstring RoundSignificantDigits(double num, int numSignificant)
{
wstringstream out(wstringstream::out);
out << fixed;
out.precision(numSignificant);
out << num;
return out.str();
}
/// <summary>
/// Convert a Number to Scientific Notation
/// </summary>
/// <param name="number">number to convert</param>
wstring ToScientificNumber(double number)
{
wstringstream out(wstringstream::out);
out << scientific << number;
return out.str();
}
}