add unittest and bugfix

src/random.js

@@ -80,7 +80,7 @@
         return a + b * log(-log(_this.uniform(0, 1)));
     };
 
-    exports.fRadio = function (v, w) {
+    exports.fRatio = function (v, w) {
         return (_this.chiSquare(v) / v) / (_this.chiSquare(w) / w);
     };
 
@@ -223,7 +223,7 @@
         do {
             x = _this.uniform(0, areaMax) / (yMax - yMin) + xMin;
             y = _this.uniform(yMin, yMax);
-        } while (y > ysf(x, xMin, xMax));
+        } while (y > usf(x, xMin, xMax));
         return x;
     };
 
@@ -251,6 +251,7 @@
     exports.hypergeometric = function (n, N, K) {
         var count = 0;
         for (var i = 0; i < n; i++, N--) {
+            var p = K / N;
             if (_this.bernoulli(p)) {
                 count++;
                 K--;

test/tests.js

@@ -7,7 +7,103 @@ describe('Random', function () {
             random.arcsine(0, 1).should.be.a('number');
         });
         it ('should generate random number with Beta', function () {
-            random.arcsine(0.5, 5, 0, 3).should.be.a('number');
+            random.beta(1, 1, 0, 1).should.be.a('number');
         });
+        it ('should generate random number with Cauchy', function () {
+            random.cauchy(1, 1).should.be.a('number');
+        });
+        it ('should generate random number with Chi-Square', function () {
+            random.chiSquare(1).should.be.a('number');
+        });
+        it ('should generate random number with Cosine', function () {
+            random.cosine(0, 1).should.be.a('number');
+        });
+        it ('should generate random number with DoubleLog', function () {
+            random.doubleLog(0, 1).should.be.a('number');
+        });
+        it ('should generate random number with Erlang', function () {
+            random.erlang(1, 1).should.be.a('number');
+        });
+        it ('should generate random number with Exponential', function () {
+            random.exponential(1, 1).should.be.a('number');
+        });
+        it ('should generate random number with ExtremeValue', function () {
+            random.extremeValue(0.5, 5, 0, 1).should.be.a('number');
+        });
+        it ('should generate random number with F Ratio', function () {
+            random.fRatio(1, 1).should.be.a('number');
+        });
+        it ('should generate random number with Gamma', function () {
+            random.gamma(1, 1, 1).should.be.a('number');
+        });
+        it ('should generate random number with Laplace', function () {
+            random.laplace(1, 1).should.be.a('number');
+        });
+        it ('should generate random number with Logarithmic', function () {
+            random.logarithmic(0, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Logistic', function () {
+            random.logistic(1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Lognormal', function () {
+            random.lognormal(1, 1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Normal', function () {
+            random.normal(1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Parabolic', function () {
+            random.parabolic(0, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Pareto', function () {
+            random.pareto(1).should.be.a('number');
+        }); 
+        it ('should generate random number with Pearson5', function () {
+            random.pearson5(1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Pearson6', function () {
+            random.pearson6(1, 1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Power', function () {
+            random.power(1).should.be.a('number');
+        }); 
+        it ('should generate random number with Rayleigh', function () {
+            random.rayleigh(1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Student\'s T', function () {
+            random.studentT(1).should.be.a('number');
+        }); 
+        it ('should generate random number with Triangular', function () {
+            random.triangular(0, 1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Uniform', function () {
+            random.uniform(0, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Weibull', function () {
+            random.weibull(1, 1, 1).should.be.a('number');
+        }); 
+        it ('should generate random number with Bernoulli', function () {
+            random.bernoulli(0.5).should.be.a('number');
+        }); 
+        it ('should generate random number with Binomial', function () {
+            random.binomial(10, 0.5).should.be.a('number');
+        }); 
+        it ('should generate random number with Geometric', function () {
+            random.geometric(0.5).should.be.a('number');
+        }); 
+        it ('should generate random number with Hypergeometric', function () {
+            random.hypergeometric(6, 10, 4).should.be.a('number');
+        }); 
+        it ('should generate random number with NegativeBinomial', function () {
+            random.negativeBinomial(5, 0.5).should.be.a('number');
+        }); 
+        it ('should generate random number with Pascal', function () {
+            random.pascal(5, 0.5).should.be.a('number');
+        }); 
+        it ('should generate random number with Poisson', function () {
+            random.poisson(5).should.be.a('number');
+        }); 
+        it ('should generate random number with UniformDiscrete', function () {
+            random.uniformDiscrete(1, 10).should.be.a('number');
+        }); 
     });
 });