10.14. Exact Math

10.14.1. Handle BigInteger And BigDecimal

Statement	Description	Return type
RETURN apoc.number.exact.add(stringA,stringB)	return the sum’s result of two large numbers	string
RETURN apoc.number.exact.sub(stringA,stringB)	return the substraction’s of two large numbers	string
RETURN apoc.number.exact.mul(stringA,stringB,[prec],[roundingModel]	return the multiplication’s result of two large numbers	string
RETURN apoc.number.exact.div(stringA,stringB,[prec],[roundingModel])	return the division’s result of two large numbers	string
RETURN apoc.number.exact.toInteger(string,[prec],[roundingMode])	return the Integer value of a large number	Integer
RETURN apoc.number.exact.toFloat(string,[prec],[roundingMode])	return the Float value of a large number	Float
RETURN apoc.number.exact.toExact(number)	return the exact value	Integer

Possible 'roundingModel' options are UP, DOWN, CEILING, FLOOR, HALF_UP, HALF_DOWN, HALF_EVEN, UNNECESSARY

The prec parameter let us to set the precision of the operation result. The default value is 0 (unlimited precision arithmetic) while for 'roundingModel' the default value is HALF_UP. For other information abouth prec and roundingModel see the documentation of MathContext

For example if we set as prec 2:

  return apoc.number.exact.div('5555.5555','5', 2, 'HALF_DOWN') as value

  ╒═════════╕
  │value    │
  ╞═════════╡
  │  1100   │
  └─────────┘

As a result we have only the first two digits precise. If we set 8 we have all the result precise

  return apoc.number.exact.div('5555.5555','5', 8, 'HALF_DOWN') as value

  ╒═════════╕
  │value    │
  ╞═════════╡
  │1111.1111│
  └─────────┘

All the functions accept as input the scientific notation as 1E6, for example:

  return apoc.number.exact.add('1E6','1E6') as value

  ╒═════════╕
  │value    │
  ╞═════════╡
  │ 2000000 │
  └─────────┘

For other information see the documentation about BigDecimal and BigInteger