simple-squiggle

A restricted subset of Squiggle
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algebra.js (1283B)


      1 // algebra
      2 //
      3 // math.js has support for symbolic computation (CAS). It can parse
      4 // expressions in an expression tree and do algebraic operations like
      5 // simplification and derivation on this tree.
      6 
      7 // load math.js (using node.js)
      8 const { simplify, parse, derivative } = require('..')
      9 
     10 // simplify an expression
     11 console.log('simplify expressions')
     12 console.log(simplify('3 + 2 / 4').toString()) // '7 / 2'
     13 console.log(simplify('2x + 3x').toString()) // '5 * x'
     14 console.log(simplify('2 * 3 * x', { x: 4 }).toString()) // '24'
     15 console.log(simplify('x^2 + x + 3 + x^2').toString()) // '2 * x ^ 2 + x + 3'
     16 console.log(simplify('x * y * -x / (x ^ 2)').toString()) // '-y'
     17 
     18 // work with an expression tree, evaluate results
     19 const f = parse('2x + x')
     20 const simplified = simplify(f)
     21 console.log(simplified.toString()) // '3 * x'
     22 console.log(simplified.evaluate({ x: 4 })) // 12
     23 console.log()
     24 
     25 // calculate a derivative
     26 console.log('calculate derivatives')
     27 console.log(derivative('2x^2 + 3x + 4', 'x').toString()) // '4 * x + 3'
     28 console.log(derivative('sin(2x)', 'x').toString()) // '2 * cos(2 * x)'
     29 
     30 // work with an expression tree, evaluate results
     31 const h = parse('x^2 + x')
     32 const dh = derivative(h, 'x')
     33 console.log(dh.toString()) // '2 * x + 1'
     34 console.log(dh.evaluate({ x: 3 })) // '7'