34 lines
1.3 KiB
JavaScript
34 lines
1.3 KiB
JavaScript
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// algebra
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//
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// math.js has support for symbolic computation (CAS). It can parse
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// expressions in an expression tree and do algebraic operations like
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// simplification and derivation on this tree.
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// load math.js (using node.js)
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var math = require('../index');
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// simplify an expression
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console.log('simplify expressions');
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console.log(math.simplify('3 + 2 / 4').toString()); // '7 / 2'
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console.log(math.simplify('2x + 3x').toString()); // '5 * x'
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console.log(math.simplify('x^2 + x + 3 + x^2').toString()); // '2 * x ^ 2 + x + 3'
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console.log(math.simplify('x * y * -x / (x ^ 2)').toString()); // '-y'
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// work with an expression tree, evaluate results
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var f = math.parse('2x + x');
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var simplified = math.simplify(f);
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console.log(simplified.toString()); // '3 * x'
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console.log(simplified.eval({x: 4})); // 12
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console.log()
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// calculate a derivative
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console.log('calculate derivatives');
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console.log(math.derivative('2x^2 + 3x + 4', 'x').toString()); // '4 * x + 3'
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console.log(math.derivative('sin(2x)', 'x').toString()); // '2 * cos(2 * x)'
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// work with an expression tree, evaluate results
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var h = math.parse('x^2 + x');
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var dh = math.derivative(h, 'x');
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console.log(dh.toString()); // '2 * x + 1'
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console.log(dh.eval({x: 3})); // '7'
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