generators/dart/math.js
/**
* @license
* Visual Blocks Language
*
* Copyright 2014 Google Inc.
* https://blockly.googlecode.com/
*
* 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.
*/
/**
* @fileoverview Generating Dart for math blocks.
* @author q.neutron@gmail.com (Quynh Neutron)
*/
'use strict';
goog.provide('Blockly.Dart.math');
goog.require('Blockly.Dart');
Blockly.Dart.addReservedWords('Math');
Blockly.Dart['math_number'] = function(block) {
// Numeric value.
var code = window.parseFloat(block.getFieldValue('NUM'));
// -4.abs() returns -4 in Dart due to strange order of operation choices.
// -4 is actually an operator and a number. Reflect this in the order.
var order = code < 0 ?
Blockly.Dart.ORDER_UNARY_PREFIX : Blockly.Dart.ORDER_ATOMIC;
return [code, order];
};
Blockly.Dart['math_arithmetic'] = function(block) {
// Basic arithmetic operators, and power.
var OPERATORS = {
'ADD': [' + ', Blockly.Dart.ORDER_ADDITIVE],
'MINUS': [' - ', Blockly.Dart.ORDER_ADDITIVE],
'MULTIPLY': [' * ', Blockly.Dart.ORDER_MULTIPLICATIVE],
'DIVIDE': [' / ', Blockly.Dart.ORDER_MULTIPLICATIVE],
'POWER': [null, Blockly.Dart.ORDER_NONE] // Handle power separately.
};
var tuple = OPERATORS[block.getFieldValue('OP')];
var operator = tuple[0];
var order = tuple[1];
var argument0 = Blockly.Dart.valueToCode(block, 'A', order) || '0';
var argument1 = Blockly.Dart.valueToCode(block, 'B', order) || '0';
var code;
// Power in Dart requires a special case since it has no operator.
if (!operator) {
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
code = 'Math.pow(' + argument0 + ', ' + argument1 + ')';
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
}
code = argument0 + operator + argument1;
return [code, order];
};
Blockly.Dart['math_single'] = function(block) {
// Math operators with single operand.
var operator = block.getFieldValue('OP');
var code;
var arg;
if (operator == 'NEG') {
// Negation is a special case given its different operator precedence.
arg = Blockly.Dart.valueToCode(block, 'NUM',
Blockly.Dart.ORDER_UNARY_PREFIX) || '0';
if (arg[0] == '-') {
// --3 is not legal in Dart.
arg = ' ' + arg;
}
code = '-' + arg;
return [code, Blockly.Dart.ORDER_UNARY_PREFIX];
}
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
if (operator == 'ABS' || operator.substring(0, 5) == 'ROUND') {
arg = Blockly.Dart.valueToCode(block, 'NUM',
Blockly.Dart.ORDER_UNARY_POSTFIX) || '0';
} else if (operator == 'SIN' || operator == 'COS' || operator == 'TAN') {
arg = Blockly.Dart.valueToCode(block, 'NUM',
Blockly.Dart.ORDER_MULTIPLICATIVE) || '0';
} else {
arg = Blockly.Dart.valueToCode(block, 'NUM',
Blockly.Dart.ORDER_NONE) || '0';
}
// First, handle cases which generate values that don't need parentheses
// wrapping the code.
switch (operator) {
case 'ABS':
code = arg + '.abs()';
break;
case 'ROOT':
code = 'Math.sqrt(' + arg + ')';
break;
case 'LN':
code = 'Math.log(' + arg + ')';
break;
case 'EXP':
code = 'Math.exp(' + arg + ')';
break;
case 'POW10':
code = 'Math.pow(10,' + arg + ')';
break;
case 'ROUND':
code = arg + '.round()';
break;
case 'ROUNDUP':
code = arg + '.ceil()';
break;
case 'ROUNDDOWN':
code = arg + '.floor()';
break;
case 'SIN':
code = 'Math.sin(' + arg + ' / 180 * Math.PI)';
break;
case 'COS':
code = 'Math.cos(' + arg + ' / 180 * Math.PI)';
break;
case 'TAN':
code = 'Math.tan(' + arg + ' / 180 * Math.PI)';
break;
}
if (code) {
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
}
// Second, handle cases which generate values that may need parentheses
// wrapping the code.
switch (operator) {
case 'LOG10':
code = 'Math.log(' + arg + ') / Math.log(10)';
break;
case 'ASIN':
code = 'Math.asin(' + arg + ') / Math.PI * 180';
break;
case 'ACOS':
code = 'Math.acos(' + arg + ') / Math.PI * 180';
break;
case 'ATAN':
code = 'Math.atan(' + arg + ') / Math.PI * 180';
break;
default:
throw 'Unknown math operator: ' + operator;
}
return [code, Blockly.Dart.ORDER_MULTIPLICATIVE];
};
Blockly.Dart['math_constant'] = function(block) {
// Constants: PI, E, the Golden Ratio, sqrt(2), 1/sqrt(2), INFINITY.
var CONSTANTS = {
'PI': ['Math.PI', Blockly.Dart.ORDER_UNARY_POSTFIX],
'E': ['Math.E', Blockly.Dart.ORDER_UNARY_POSTFIX],
'GOLDEN_RATIO': ['(1 + Math.sqrt(5)) / 2', Blockly.Dart.ORDER_MULTIPLICATIVE],
'SQRT2': ['Math.SQRT2', Blockly.Dart.ORDER_UNARY_POSTFIX],
'SQRT1_2': ['Math.SQRT1_2', Blockly.Dart.ORDER_UNARY_POSTFIX],
'INFINITY': ['double.INFINITY', Blockly.Dart.ORDER_ATOMIC]
};
var constant = block.getFieldValue('CONSTANT');
if (constant != 'INFINITY') {
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
}
return CONSTANTS[constant];
};
Blockly.Dart['math_number_property'] = function(block) {
// Check if a number is even, odd, prime, whole, positive, or negative
// or if it is divisible by certain number. Returns true or false.
var number_to_check = Blockly.Dart.valueToCode(block, 'NUMBER_TO_CHECK',
Blockly.Dart.ORDER_MULTIPLICATIVE);
if (!number_to_check) {
return ['false', Blockly.Python.ORDER_ATOMIC];
}
var dropdown_property = block.getFieldValue('PROPERTY');
var code;
if (dropdown_property == 'PRIME') {
// Prime is a special case as it is not a one-liner test.
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var functionName = Blockly.Dart.provideFunction_(
'math_isPrime',
[ 'bool ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ + '(n) {',
' // https://en.wikipedia.org/wiki/Primality_test#Naive_methods',
' if (n == 2 || n == 3) {',
' return true;',
' }',
' // False if n is null, negative, is 1, or not whole.',
' // And false if n is divisible by 2 or 3.',
' if (n == null || n <= 1 || n % 1 != 0 || n % 2 == 0 ||' +
' n % 3 == 0) {',
' return false;',
' }',
' // Check all the numbers of form 6k +/- 1, up to sqrt(n).',
' for (var x = 6; x <= Math.sqrt(n) + 1; x += 6) {',
' if (n % (x - 1) == 0 || n % (x + 1) == 0) {',
' return false;',
' }',
' }',
' return true;',
'}']);
code = functionName + '(' + number_to_check + ')';
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
}
switch (dropdown_property) {
case 'EVEN':
code = number_to_check + ' % 2 == 0';
break;
case 'ODD':
code = number_to_check + ' % 2 == 1';
break;
case 'WHOLE':
code = number_to_check + ' % 1 == 0';
break;
case 'POSITIVE':
code = number_to_check + ' > 0';
break;
case 'NEGATIVE':
code = number_to_check + ' < 0';
break;
case 'DIVISIBLE_BY':
var divisor = Blockly.Dart.valueToCode(block, 'DIVISOR',
Blockly.Dart.ORDER_MULTIPLICATIVE);
if (!divisor) {
return ['false', Blockly.Python.ORDER_ATOMIC];
}
code = number_to_check + ' % ' + divisor + ' == 0';
break;
}
return [code, Blockly.Dart.ORDER_EQUALITY];
};
Blockly.Dart['math_change'] = function(block) {
// Add to a variable in place.
var argument0 = Blockly.Dart.valueToCode(block, 'DELTA',
Blockly.Dart.ORDER_ADDITIVE) || '0';
var varName = Blockly.Dart.variableDB_.getName(block.getFieldValue('VAR'),
Blockly.Variables.NAME_TYPE);
return varName + ' = (' + varName + ' is num ? ' + varName + ' : 0) + ' +
argument0 + ';\n';
};
// Rounding functions have a single operand.
Blockly.Dart['math_round'] = Blockly.Dart['math_single'];
// Trigonometry functions have a single operand.
Blockly.Dart['math_trig'] = Blockly.Dart['math_single'];
Blockly.Dart['math_on_list'] = function(block) {
// Math functions for lists.
var func = block.getFieldValue('OP');
var list = Blockly.Dart.valueToCode(block, 'LIST',
Blockly.Dart.ORDER_NONE) || '[]';
var code;
switch (func) {
case 'SUM':
var functionName = Blockly.Dart.provideFunction_(
'math_sum',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' num sumVal = 0;',
' myList.forEach((num entry) {sumVal += entry;});',
' return sumVal;',
'}']);
code = functionName + '(' + list + ')';
break;
case 'MIN':
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var functionName = Blockly.Dart.provideFunction_(
'math_min',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' if (myList.isEmpty) return null;',
' num minVal = myList[0];',
' myList.forEach((num entry) ' +
'{minVal = Math.min(minVal, entry);});',
' return minVal;',
'}']);
code = functionName + '(' + list + ')';
break;
case 'MAX':
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var functionName = Blockly.Dart.provideFunction_(
'math_max',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' if (myList.isEmpty) return null;',
' num maxVal = myList[0];',
' myList.forEach((num entry) ' +
'{maxVal = Math.max(maxVal, entry);});',
' return maxVal;',
'}']);
code = functionName + '(' + list + ')';
break;
case 'AVERAGE':
// This operation exclude null and values that are not int or float:
// math_mean([null,null,"aString",1,9]) == 5.0.
var functionName = Blockly.Dart.provideFunction_(
'math_average',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' // First filter list for numbers only.',
' List localList = new List.from(myList);',
' localList.removeMatching((a) => a is! num);',
' if (localList.isEmpty) return null;',
' num sumVal = 0;',
' localList.forEach((num entry) {sumVal += entry;});',
' return sumVal / localList.length;',
'}']);
code = functionName + '(' + list + ')';
break;
case 'MEDIAN':
var functionName = Blockly.Dart.provideFunction_(
'math_median',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' // First filter list for numbers only, then sort, ' +
'then return middle value',
' // or the average of two middle values if list has an ' +
'even number of elements.',
' List localList = new List.from(myList);',
' localList.removeMatching((a) => a is! num);',
' if (localList.isEmpty) return null;',
' localList.sort((a, b) => (a - b));',
' int index = localList.length ~/ 2;',
' if (localList.length % 2 == 1) {',
' return localList[index];',
' } else {',
' return (localList[index - 1] + localList[index]) / 2;',
' }',
'}']);
code = functionName + '(' + list + ')';
break;
case 'MODE':
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
// As a list of numbers can contain more than one mode,
// the returned result is provided as an array.
// Mode of [3, 'x', 'x', 1, 1, 2, '3'] -> ['x', 1].
var functionName = Blockly.Dart.provideFunction_(
'math_modes',
[ 'List ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List values) {',
' List modes = [];',
' List counts = [];',
' int maxCount = 0;',
' for (int i = 0; i < values.length; i++) {',
' var value = values[i];',
' bool found = false;',
' int thisCount;',
' for (int j = 0; j < counts.length; j++) {',
' if (counts[j][0] == value) {',
' thisCount = ++counts[j][1];',
' found = true;',
' break;',
' }',
' }',
' if (!found) {',
' counts.add([value, 1]);',
' thisCount = 1;',
' }',
' maxCount = Math.max(thisCount, maxCount);',
' }',
' for (int j = 0; j < counts.length; j++) {',
' if (counts[j][1] == maxCount) {',
' modes.add(counts[j][0]);',
' }',
' }',
' return modes;',
'}']);
code = functionName + '(' + list + ')';
break;
case 'STD_DEV':
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var functionName = Blockly.Dart.provideFunction_(
'math_standard_deviation',
[ 'num ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' // First filter list for numbers only.',
' List numbers = new List.from(myList);',
' numbers.removeMatching((a) => a is! num);',
' if (numbers.isEmpty) return null;',
' num n = numbers.length;',
' num sum = 0;',
' numbers.forEach((x) => sum += x);',
' num mean = sum / n;',
' num sumSquare = 0;',
' numbers.forEach((x) => sumSquare += ' +
'Math.pow(x - mean, 2));',
' return Math.sqrt(sumSquare / n);',
'}']);
code = functionName + '(' + list + ')';
break;
case 'RANDOM':
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var functionName = Blockly.Dart.provideFunction_(
'math_random_item',
[ 'dynamic ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ +
'(List myList) {',
' int x = new Math.Random().nextInt(myList.length);',
' return myList[x];',
'}']);
code = functionName + '(' + list + ')';
break;
default:
throw 'Unknown operator: ' + func;
}
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
};
Blockly.Dart['math_modulo'] = function(block) {
// Remainder computation.
var argument0 = Blockly.Dart.valueToCode(block, 'DIVIDEND',
Blockly.Dart.ORDER_MULTIPLICATIVE) || '0';
var argument1 = Blockly.Dart.valueToCode(block, 'DIVISOR',
Blockly.Dart.ORDER_MULTIPLICATIVE) || '0';
var code = argument0 + ' % ' + argument1;
return [code, Blockly.Dart.ORDER_MULTIPLICATIVE];
};
Blockly.Dart['math_constrain'] = function(block) {
// Constrain a number between two limits.
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var argument0 = Blockly.Dart.valueToCode(block, 'VALUE',
Blockly.Dart.ORDER_NONE) || '0';
var argument1 = Blockly.Dart.valueToCode(block, 'LOW',
Blockly.Dart.ORDER_NONE) || '0';
var argument2 = Blockly.Dart.valueToCode(block, 'HIGH',
Blockly.Dart.ORDER_NONE) || 'double.INFINITY';
var code = 'Math.min(Math.max(' + argument0 + ', ' + argument1 + '), ' +
argument2 + ')';
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
};
Blockly.Dart['math_random_int'] = function(block) {
// Random integer between [X] and [Y].
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
var argument0 = Blockly.Dart.valueToCode(block, 'FROM',
Blockly.Dart.ORDER_NONE) || '0';
var argument1 = Blockly.Dart.valueToCode(block, 'TO',
Blockly.Dart.ORDER_NONE) || '0';
var functionName = Blockly.Dart.provideFunction_(
'math_random_int',
[ 'int ' + Blockly.Dart.FUNCTION_NAME_PLACEHOLDER_ + '(num a, num b) {',
' if (a > b) {',
' // Swap a and b to ensure a is smaller.',
' num c = a;',
' a = b;',
' b = c;',
' }',
' return new Math.Random().nextInt(b - a + 1) + a;',
'}']);
var code = functionName + '(' + argument0 + ', ' + argument1 + ')';
return [code, Blockly.Dart.ORDER_UNARY_POSTFIX];
};
Blockly.Dart['math_random_float'] = function(block) {
// Random fraction between 0 and 1.
Blockly.Dart.definitions_['import_dart_math'] =
'import \'dart:math\' as Math;';
return ['new Math.Random().nextDouble()', Blockly.Dart.ORDER_UNARY_POSTFIX];
};