$mol_chance: normalize chances by their values sum

chance/chance.test.ts

@@ -16,35 +16,7 @@ namespace $ {
 
 		},
 
-		'Probability sum should not be more than 100'() {
-
-			$mol_assert_fail( ()=> {
-
-				$mol_chance(
-					[ 50, ()=> 1 ],
-					[ 50, ()=> 2 ],
-					[ 1, ()=> 3 ],
-				)
-
-			} )
-
-		},
-
-		'Probability sum should not be less than 100'() {
-
-			$mol_assert_fail( ()=> {
-
-				$mol_chance(
-					[ 50, ()=> 1 ],
-					[ 30, ()=> 2 ],
-					[ 10, ()=> 3 ],
-				)
-
-			} )
-
-		},
-
-		"Result should be one of chance's fn return values"() {
+		'Result should be one of chance`s fn return values'() {
 
 			const result = $mol_chance(
 				[ 10, ()=> 1 ],
@@ -64,51 +36,17 @@ namespace $ {
 
 		},
 
-		"100 percent chance's value should be returned every time"() {
-
-			var match_count = 0
-			for ( var i = 0; i < 500; ++ i ) {
-
-				const result = $mol_chance( [ 100, ()=> 0 ] )
-
-				if ( result === 0 ) match_count += 1
-
-			}
-
-			$mol_assert_equal( match_count, 500 )
-
-		},
-
-		"0 percent chances's value should never be returned"() {
-
-			var match_count = 0
-			for ( var i = 0; i < 500; ++ i ) {
-
-				const result = $mol_chance(
-					[ 60, ()=> 60 ],
-					[ 0, ()=> 0 ],
-					[ 40, ()=> 40 ],
-				)
-
-				if ( result === 0 ) match_count += 1
-
-			}
-
-			$mol_assert_equal( match_count, 0 )
-
-		},
-
-		"Chance value sholud be called if it is a function"() {
+		'Chance value sholud be called if it is a function'() {
 
 			const result = $mol_chance(
-				[ 100, ()=> ( { prop: false } ) ]
+				[ 1, ()=> ( { prop: false } ) ]
 			)
 
 			$mol_assert_like( result, { prop: false } )
 
 		},
 
-		"Correct type inference"() {
+		'Correct type inference'() {
 
 			const result = $mol_chance(
 				[ 10, ()=> 1 ],

chance/chance.ts

@@ -9,34 +9,27 @@ namespace $ {
 		const prob_sum = chance_list.reduce( ( sum, { 0: prob } )=> {
 			if (
 				prob < 0
-				|| prob > 100
 				|| Number.isNaN( prob )
 				|| prob === Infinity
 			) {
-				throw new Error( `Incorrect probability value: ${ prob }, only numbers from 0 to 100 are allowed` )
+				throw new Error( `Incorrect probability value: ${ prob }, bun only positive numbers are allowed` )
 			}
 
 			sum += prob
 
-			if ( sum > 100 ) {
-				throw new Error( `Incorrect probability sum: ${ sum }, but 100 is max` )
-			}
-
 			return sum
 		}, 0 )
 
-		if ( prob_sum < 100 ) {
-			throw new Error( `Incorrect probability sum: ${ prob_sum }, but needs 100` )
-		}
-
 		const random = Math.random()
 
 		var prob_total = 0
-		for ( var i = 0; i < chance_list.length; i ++ ) {
+		for( var i = 0; i < chance_list.length; ++ i ) {
+
+			var { 0: prob_raw, 1: fn } = chance_list[ i ]
 
-			const { 0: prob_percent, 1: fn } = chance_list[ i ]
+			var prob_percent = ( prob_raw / prob_sum ) * 100
 
-			const prob = prob_total + prob_percent / 100
+			var prob = prob_total + ( prob_percent / 100 )
 
 			if ( random < prob ) {
 
@@ -53,7 +46,7 @@ namespace $ {
 
 		}
 
-		throw new Error( `Incorrect probability sum: ${ prob_sum }, but needs 100` )
+		throw new Error( `Incorrect probability sum: ${ prob_sum }` )
 
 	}
 

chance/readme.md

@@ -20,4 +20,4 @@ const color = $mol_chance(
 // in 5% will be called function to generate random color.
 ```
 
-**Total sum of probabilities should be 100.**
+Note: chances are normalized by their values sum. Example: chances [ 20, 50 ] will be converted to ~71% and ~29% respectively.