title: Non-exponential formatted float
body: <p>I have a UTF-8 formatted data file that contains thousands of floating point numbers.  At the time it was designed the developers decided to omit the 'e' in the exponential notation to save space.  Therefore the data looks like:</p>
  
  <pre><code> 1.85783+16 0.000000+0 1.900000+6-3.855418-4 1.958263+6 7.836995-4
  -2.000000+6 9.903130-4 2.100000+6 1.417469-3 2.159110+6 1.655700-3
   2.200000+6 1.813662-3-2.250000+6-1.998687-3 2.300000+6 2.174219-3
   2.309746+6 2.207278-3 2.400000+6 2.494469-3 2.400127+6 2.494848-3
  -2.500000+6 2.769739-3 2.503362+6 2.778185-3 2.600000+6 3.020353-3
   2.700000+6 3.268572-3 2.750000+6 3.391230-3 2.800000+6 3.512625-3
   2.900000+6 3.750746-3 2.952457+6 3.872690-3 3.000000+6 3.981166-3
   3.202512+6 4.437824-3 3.250000+6 4.542310-3 3.402356+6 4.861319-3
  </code></pre>
  
  <p>The problem is float.Parse() will not work with this format.  The intermediate solution I had was,</p>
  
  <pre><code>    protected static float ParseFloatingPoint(string data)
      {
  
          int signPos;
          char replaceChar = '+';
  
          // Skip over first character so that a leading + is not caught
          signPos = data.IndexOf(replaceChar, 1);
  
          // Didn't find a '+', so lets see if there's a '-'
          if (signPos == -1)
          {
              replaceChar = '-';
              signPos = data.IndexOf('-', 1);
          }
  
          // Found either a '+' or '-'
          if (signPos != -1)
          {
              // Create a new char array with an extra space to accomodate the 'e'
              char[] newData = new char[EntryWidth + 1];
  
              // Copy from string up to the sign
              for (int i = 0; i &lt; signPos; i++)
              {
                  newData[i] = data[i];
              }
  
              // Replace the sign with an 'e + sign'
              newData[signPos] = 'e';
              newData[signPos + 1] = replaceChar;
  
              // Copy the rest of the string
              for (int i = signPos + 2; i &lt; EntryWidth + 1; i++)
              {
                  newData[i] = data[i - 1];
              }
  
              return float.Parse(new string(newData), NumberStyles.Float, CultureInfo.InvariantCulture);
          }
          else
          {
              return float.Parse(data, NumberStyles.Float, CultureInfo.InvariantCulture);
          }
      }
  </code></pre>
  
  <p>I can't call a simple String.Replace() because it will replace any leading negative signs.  I could use substrings but then I'm making LOTS of extra strings and I'm concerned about the performance.</p>
  
  <p>Does anyone have a more elegant solution to this?</p>