title: What is the Objective-C equivalent of the Java Math library?
body: <p>What library/header/class is equivalent to the Java <code>Math</code> class?</p>
  
  <hr>
  
  <p><strong>Background &amp; bonus question:</strong></p>
  
  <p>I'm trying to port this function to Objective-C from Java. Should I rewrite it, or can I copy and paste and rewrite only the parts that are syntactically different? (In other words, will the Java behave the same way if it were run as Objective-C or C?)</p>
  
  <p>Here's the monster function in Java. It essentially is the <a href="http://en.wikipedia.org/wiki/Vincenty%27s_formulae" rel="nofollow">Vincinty Formula</a>:</p>
  
  <pre><code>private double vincentyFormula(GeoLocation location, int formula) {
      double a = 6378137;
      double b = 6356752.3142;
      double f = 1 / 298.257223563; // WGS-84 ellipsiod
      double L = Math.toRadians(location.getLongitude() - getLongitude());
      double U1 = Math
              .atan((1 - f) * Math.tan(Math.toRadians(getLatitude())));
      double U2 = Math.atan((1 - f)
              * Math.tan(Math.toRadians(location.getLatitude())));
      double sinU1 = Math.sin(U1), cosU1 = Math.cos(U1);
      double sinU2 = Math.sin(U2), cosU2 = Math.cos(U2);
  
      double lambda = L;
      double lambdaP = 2 * Math.PI;
      double iterLimit = 20;
      double sinLambda = 0;
      double cosLambda = 0;
      double sinSigma = 0;
      double cosSigma = 0;
      double sigma = 0;
      double sinAlpha = 0;
      double cosSqAlpha = 0;
      double cos2SigmaM = 0;
      double C;
      while (Math.abs(lambda - lambdaP) &gt; 1e-12 &amp;&amp; --iterLimit &gt; 0) {
          sinLambda = Math.sin(lambda);
          cosLambda = Math.cos(lambda);
          sinSigma = Math.sqrt((cosU2 * sinLambda) * (cosU2 * sinLambda)
                  + (cosU1 * sinU2 - sinU1 * cosU2 * cosLambda)
                  * (cosU1 * sinU2 - sinU1 * cosU2 * cosLambda));
          if (sinSigma == 0)
              return 0; // co-incident points
          cosSigma = sinU1 * sinU2 + cosU1 * cosU2 * cosLambda;
          sigma = Math.atan2(sinSigma, cosSigma);
          sinAlpha = cosU1 * cosU2 * sinLambda / sinSigma;
          cosSqAlpha = 1 - sinAlpha * sinAlpha;
          cos2SigmaM = cosSigma - 2 * sinU1 * sinU2 / cosSqAlpha;
          if (Double.isNaN(cos2SigmaM))
              cos2SigmaM = 0; // equatorial line: cosSqAlpha=0 (ß6)
          C = f / 16 * cosSqAlpha * (4 + f * (4 - 3 * cosSqAlpha));
          lambdaP = lambda;
          lambda = L
                  + (1 - C)
                  * f
                  * sinAlpha
                  * (sigma + C
                          * sinSigma
                          * (cos2SigmaM + C * cosSigma
                                  * (-1 + 2 * cos2SigmaM * cos2SigmaM)));
      }
      if (iterLimit == 0)
          return Double.NaN; // formula failed to converge
  
      double uSq = cosSqAlpha * (a * a - b * b) / (b * b);
      double A = 1 + uSq / 16384
              * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)));
      double B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)));
      double deltaSigma = B
              * sinSigma
              * (cos2SigmaM + B
                      / 4
                      * (cosSigma * (-1 + 2 * cos2SigmaM * cos2SigmaM) - B
                              / 6 * cos2SigmaM
                              * (-3 + 4 * sinSigma * sinSigma)
                              * (-3 + 4 * cos2SigmaM * cos2SigmaM)));
      double distance = b * A * (sigma - deltaSigma);
  
      // initial bearing
      double fwdAz = Math.toDegrees(Math.atan2(cosU2 * sinLambda, cosU1
              * sinU2 - sinU1 * cosU2 * cosLambda));
      // final bearing
      double revAz = Math.toDegrees(Math.atan2(cosU1 * sinLambda, -sinU1
              * cosU2 + cosU1 * sinU2 * cosLambda));
      if (formula == DISTANCE) {
          return distance;
      } else if (formula == INITIAL_BEARING) {
          return fwdAz;
      } else if (formula == FINAL_BEARING) {
          return revAz;
      } else { // should never happpen
          return Double.NaN;
      }
    }
  </code></pre>