text: 'use strict';
  
  // FUNCTIONS //
  
  var abs = Math.abs,
  	arctan = Math.atan;
  
  
  // VARIABLES //
  
  var ONE_OVER_PI = 1 / Math.PI;
  
  
  // CDF //
  
  /**
  * FUNCTION: cdf( x, gamma, x0 )
  *	Evaluates the cumulative distribution function (CDF) for a Cauchy distribution with scale parameter `gamma` and location parameter `x0` at a value `x`.
  *
  * @param {Number} x - input value
  * @param {Number} gamma - scale parameter
  * @param {Number} x0 - location parameter
  * @returns {Number} evaluated CDF
  */
  function cdf( x, gamma, x0 ) {
  	var z = ( x - x0 ) / gamma;
  	z = -abs( z );
  	if ( x < x0 ) {
  		return -arctan( 1/z ) * ONE_OVER_PI;
  	} else {
  		return 1 + arctan( 1/z ) * ONE_OVER_PI;
  	}
  } // end FUNCTION cdf()
  
  
  // EXPORTS //
  
  module.exports = cdf;
  