text: var vows = require('vows');
  var assert = require('assert');
  var suite = vows.describe('jStat.distribution');
  
  require('../env.js');
  
  suite.addBatch({
    'lognormal pdf': {
      'topic': function() {
        return jStat;
      },
      // Checked against R's dlnorm(x, meanlog = 0, sdlog = 1, log = FALSE)
      //   options(digits=10)
      //   dlnorm(c(-2, 0, 4), 4, 5)
      'check pdf calculation': function(jStat) {
        var tol = 0.0000001;
        assert.epsilon(tol, jStat.lognormal.pdf(-2, 4, 5), 0);
        assert.epsilon(tol, jStat.lognormal.pdf(0, 4, 5), 0);
        assert.epsilon(tol, jStat.lognormal.pdf(4, 4, 5), 0.01739974114);
      }
    },
    'lognormal cdf': {
      'topic': function() {
        return jStat;
      },
      // Checked against R's
      // plnorm(q, meanlog = 0, sdlog = 1, lower.tail = TRUE, log.p = FALSE)
      //   options(digits=10)
      //   plnorm(c(-2, 0, 4), 4, 5)
      'check cdf calculation': function(jStat) {
        var tol = 0.0000001;
        assert.epsilon(tol, jStat.lognormal.cdf(-2, 4, 5), 0);
        assert.epsilon(tol, jStat.lognormal.cdf(0, 4, 5), 0);
        assert.epsilon(tol, jStat.lognormal.cdf(4, 4, 5), 0.3005772067);
      }
    },
  });
  
  suite.export(module);
  