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You're viewing version 1.2.0 of with-precision. The latest stable version of Clojure Core is 1.3.0.

1.2.0

1.2.0
1.3.0

with-precision

Sets the precision and rounding mode to be used for BigDecimal operations.

Usage: (with-precision 10 (/ 1M 3))
or: (with-precision 10 :rounding HALF_DOWN (/ 1M 3))

The rounding mode is one of CEILING, FLOOR, HALF_UP, HALF_DOWN,
HALF_EVEN, UP, DOWN and UNNECESSARY; it defaults to HALF_UP.

1 Example top

link | changes
```
;; The "M" suffix denotes a BigDecimal instance
;; http://download.oracle.com/javase/6/docs/api/java/math/BigDecimal.html

user=> (with-precision 10 (/ 1M 6))
0.1666666667M

user=> (.floatValue 0.1666666667M)
0.16666667
```
;; The "M" suffix denotes a BigDecimal instance ;; http://download.oracle.com/javase/6/docs/api/java/math/BigDecimal.html user=> (with-precision 10 (/ 1M 6)) 0.1666666667M user=> (.floatValue 0.1666666667M) 0.16666667

Source clojure/core.clj:4003 top

(defmacro with-precision
  "Sets the precision and rounding mode to be used for BigDecimal operations.

  Usage: (with-precision 10 (/ 1M 3))
  or:    (with-precision 10 :rounding HALF_DOWN (/ 1M 3))

  The rounding mode is one of CEILING, FLOOR, HALF_UP, HALF_DOWN,
  HALF_EVEN, UP, DOWN and UNNECESSARY; it defaults to HALF_UP."
  {:added "1.0"}
  [precision & exprs]
    (let [[body rm] (if (= (first exprs) :rounding)
                      [(next (next exprs))
                       `((. java.math.RoundingMode ~(second exprs)))]
                      [exprs nil])]
      `(binding [*math-context* (java.math.MathContext. ~precision ~@rm)]
         ~@body)))

Vars in clojure.core/with-precision: defmacro let *math-context* apply binding concat list seq vector

Used in 0 other vars

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Clojure Core

Namespaces

with-precision

clojure.core

1 Example top

See Also top

Source clojure/core.clj:4003 top

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