chore: refractor lognormal/cdf benchmark.js and restore negative-binomial

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Author: saurabhraghuvanshii

lib/node_modules/@stdlib/stats/base/dists/lognormal/cdf/benchmark/benchmark.js

@@ -21,7 +21,7 @@
 // MODULES //
 
 var bench = require( '@stdlib/bench' );
-var randu = require( '@stdlib/random/base/randu' );
+var uniform = require( '@stdlib/random/base/uniform' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var EPS = require( '@stdlib/constants/float64/eps' );
 var pkg = require( './../package.json' ).name;
@@ -39,9 +39,9 @@ bench( pkg, function benchmark( b ) {
 
 	b.tic();
 	for ( i = 0; i < b.iterations; i++ ) {
-		x = ( randu()*100.0 ) - 100;
-		mu = ( randu()*100.0 ) - 50.0;
-		sigma = ( randu()*20.0 ) + EPS;
+		x = uniform( -100.0, 100.0 );
+		mu = uniform( -50.0, 50.0 );
+		sigma = uniform( EPS, 20.0 );
 		y = cdf( x, mu, sigma );
 		if ( isnan( y ) ) {
 			b.fail( 'should not return NaN' );
@@ -69,7 +69,7 @@ bench( pkg+':factory', function benchmark( b ) {
 
 	b.tic();
 	for ( i = 0; i < b.iterations; i++ ) {
-		x = randu() * 50.0;
+		x = uniform( 0.0, 50.0 );
 		y = mycdf( x );
 		if ( isnan( y ) ) {
 			b.fail( 'should not return NaN' );

lib/node_modules/@stdlib/stats/base/dists/negative-binomial/cdf/benchmark/benchmark.js

@@ -0,0 +1,85 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var ceil = require( '@stdlib/math/base/special/ceil' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var randu = require( '@stdlib/random/base/randu' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var pkg = require( './../package.json' ).name;
+var cdf = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var r;
+	var p;
+	var x;
+	var y;
+	var i;
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		x = randu()*100.0;
+		r = ceil( randu()*100.0 );
+		p = ( randu()*1.0 ) + EPS;
+		y = cdf( x, r, p );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( pkg+':factory', function benchmark( b ) {
+	var mycdf;
+	var r;
+	var p;
+	var x;
+	var y;
+	var i;
+
+	r = 80;
+	p = 0.4;
+	mycdf = cdf.factory( r, p );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		x = ( randu()*100 );
+		y = mycdf( x );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});