fix #3

Author: make-github-pseudonymous-again

js/dist/random.js

@@ -90,13 +90,37 @@ var randint = function ( i , j ) {
 
 exports.randint = randint ;
 
-/* js/src/001-api/002-sample.js */
+/* js/src/001-api/002-randrange.js */
+
+/**
+ * Return a randomly selected element from range(start, stop, step).
+ */
+
+var randrange = function ( start , stop , step ) {
+
+	// TODO handle empty ranges
+
+	if ( stop === undefined ) return randint( 0 , start ) ;
+	if ( step === undefined ) step = 1 ;
+
+	if ( stop >= start ) {
+		return start + step * randint( 0 , Math.floor( ( stop - start ) / step ) ) ;
+	}
+	else {
+		return start + step * randint( 0 , Math.floor( ( start - stop ) / -step ) ) ;
+	}
+
+} ;
+
+exports.randrange = randrange ;
+
+/* js/src/001-api/003-sample.js */
 
 var sample = _fisheryates( randint ) ;
 
 exports.sample = sample ;
 
-/* js/src/001-api/003-shuffle.js */
+/* js/src/001-api/004-shuffle.js */
 
 var shuffle = _shuffle( sample ) ;
 

js/dist/random.js.map

@@ -0,0 +1,22 @@
+
+/**
+ * Return a randomly selected element from range(start, stop, step).
+ */
+
+var randrange = function ( start , stop , step ) {
+
+	// TODO handle empty ranges
+
+	if ( stop === undefined ) return randint( 0 , start ) ;
+	if ( step === undefined ) step = 1 ;
+
+	if ( stop >= start ) {
+		return start + step * randint( 0 , Math.floor( ( stop - start ) / step ) ) ;
+	}
+	else {
+		return start + step * randint( 0 , Math.floor( ( start - stop ) / -step ) ) ;
+	}
+
+} ;
+
+exports.randrange = randrange ;

js/dist/random.min.js

@@ -0,0 +1,40 @@
+
+var util, type;
+
+util = require( "util" );
+
+type = require( "aureooms-js-type" );
+
+
+
+test( "randrange only stop", function () {
+
+	var i, n, r, rj, check;
+
+	n = 5000;
+	rj = n;
+
+	check = function () {
+		ok( r < rj, util.format( "%s < %s", r, rj ) );
+		ok( r >= 0, util.format( "%s >= %s", r, 0 ) );
+		ok( type.isint(r), util.format( "type.isint(%s)", r ) );
+	};
+
+	for ( i = 1 ; i < n ; ++i ) {
+		r = random.randrange( rj );
+
+		check();
+
+		--rj;
+	}
+
+	for ( i = 1 ; i < n ; ++i ) {
+		r = random.randrange( rj );
+
+		check();
+
+		++rj;
+	}
+
+
+});

js/src/001-api/002-randrange.js

@@ -0,0 +1,52 @@
+
+var util, type;
+
+util = require( "util" );
+
+type = require( "aureooms-js-type" );
+
+test( "randrange with negative step", function () {
+
+	var i, n, r, ri, rj, check , step;
+
+	n = 5000;
+	ri = -n;
+	rj = n;
+
+	check = function () {
+		ok( r <= rj, util.format( "%s <= %s", r, rj ) );
+		ok( r > ri, util.format( "%s > %s", r, ri ) );
+		ok( (rj - r) % (-step) === 0, util.format( "(%s - %s) %% (-%s) === 0", rj, r ,step ) );
+		ok( type.isint(r), util.format( "type.isint(%s)", r ) );
+	};
+
+	for ( step = -3 ; step <= -1 ; ++step ) {
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( rj, ri , step );
+
+			check();
+
+			++ri;
+		}
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( rj, ri , step );
+
+			check();
+
+			--ri;
+			--rj;
+		}
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( rj, ri , step );
+
+			check();
+
+			++rj;
+		}
+
+	}
+
+});

js/src/001-api/002-sample.js renamed to js/src/001-api/003-sample.js

@@ -0,0 +1,52 @@
+
+var util, type;
+
+util = require( "util" );
+
+type = require( "aureooms-js-type" );
+
+test( "randrange with positive step", function () {
+
+	var i, n, r, ri, rj, check , step;
+
+	n = 5000;
+	ri = -n;
+	rj = n;
+
+	check = function () {
+		ok( r < rj, util.format( "%s < %s", r, rj ) );
+		ok( r >= ri, util.format( "%s >= %s", r, ri ) );
+		ok( (r - ri) % step === 0, util.format( "(%s - %s) %% %s === 0", r, ri ,step ) );
+		ok( type.isint(r), util.format( "type.isint(%s)", r ) );
+	};
+
+	for ( step = 1 ; step <= 3 ; ++step ) {
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( ri, rj , step );
+
+			check();
+
+			++ri;
+		}
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( ri, rj , step );
+
+			check();
+
+			--ri;
+			--rj;
+		}
+
+		for ( i = 0 ; i < n ; ++i ) {
+			r = random.randrange( ri, rj , step );
+
+			check();
+
+			++rj;
+		}
+
+	}
+
+});

js/src/001-api/003-shuffle.js renamed to js/src/001-api/004-shuffle.js

@@ -0,0 +1,50 @@
+
+var util, type;
+
+util = require( "util" );
+
+type = require( "aureooms-js-type" );
+
+
+
+test( "randrange without step", function () {
+
+	var i, n, r, ri, rj, check;
+
+	n = 5000;
+	ri = -n;
+	rj = n;
+
+	check = function () {
+		ok( r < rj, util.format( "%s < %s", r, rj ) );
+		ok( r >= ri, util.format( "%s >= %s", r, ri ) );
+		ok( type.isint(r), util.format( "type.isint(%s)", r ) );
+	};
+
+	for ( i = 0 ; i < n ; ++i ) {
+		r = random.randrange( ri, rj );
+
+		check();
+
+		++ri;
+	}
+
+	for ( i = 0 ; i < n ; ++i ) {
+		r = random.randrange( ri, rj );
+
+		check();
+
+		--ri;
+		--rj;
+	}
+
+	for ( i = 0 ; i < n ; ++i ) {
+		r = random.randrange( ri, rj );
+
+		check();
+
+		++rj;
+	}
+
+
+});