35 lines
1.3 KiB
JavaScript
35 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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const { simplify, parse, derivative } = require('..')
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// simplify an expression
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console.log('simplify expressions')
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console.log(simplify('3 + 2 / 4').toString()) // '7 / 2'
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console.log(simplify('2x + 3x').toString()) // '5 * x'
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console.log(simplify('2 * 3 * x', { x: 4 }).toString()) // '24'
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console.log(simplify('x^2 + x + 3 + x^2').toString()) // '2 * x ^ 2 + x + 3'
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console.log(simplify('x * y * -x / (x ^ 2)').toString()) // '-y'
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// work with an expression tree, evaluate results
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const f = parse('2x + x')
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const simplified = simplify(f)
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console.log(simplified.toString()) // '3 * x'
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console.log(simplified.evaluate({ 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(derivative('2x^2 + 3x + 4', 'x').toString()) // '4 * x + 3'
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console.log(derivative('sin(2x)', 'x').toString()) // '2 * cos(2 * x)'
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// work with an expression tree, evaluate results
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const h = parse('x^2 + x')
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const dh = derivative(h, 'x')
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console.log(dh.toString()) // '2 * x + 1'
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console.log(dh.evaluate({ x: 3 })) // '7'
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