You are viewing an old version of this page. View the current version.
Compare with Current |
View Page History
This page is in progress and is the artifact for http://dev.clojure.org/jira/browse/CLJ-718.
Numbers and Math
As of version 1.3, Clojure provides full support for JVM primitive values, making it possible to write high performance, idiomatic Clojure code for numeric applications.
Numeric Types
- Primitives - These are raw JVM primitives, not object references. They are by far the fastest way to do math on the JVM. Clojure provides support for the full set of JVM primitives internally, but
- Boxed Numbers - These are full objects that extend the java.lang.Number class. Clojure uses the full set of types built into the JVM (Integer, Long, BigInteger, Float, Double, BigDecimal) as well as two additional types:
- clojure.lang.Ratio, for expressing rational numbers that cannot be expressed as a decimal without truncation
- clojure.lang.BigInt, which is similar to Java's java.math.BigInteger in allowing integer sizes exceeding 64 bits, but provides better performance by delegating to native operations when small enough.
Literals
It is possible to create most types of numbers as literals directly within Clojure code:
Type |
Literal Syntax |
Examples |
|---|---|---|
primitive long (decimal) |
a number, with no leading zeroes |
42 |
primitive long (octal) |
a number with a leading zero |
052 |
primitive long (hexadecimal) |
a number prefixed by 0x |
0x2A |
primitive long (arbitrary base) |
base + r + the number |
2r101010, 12r36 |
primitive double (standard notation) |
a number containing a decimal point |
98.8, 3.3 |
primitive double (scientific notation) |
coefficient + E + sign (optional) + exponent |
6.0221479E+23, 6.67428E-11 |
rational number |
number including a slash, with no spaces |
1/3, 33/16 |
fixed point decimal (java.lang.BigDecimal) |
number with M suffix |
9.99M |
big integer (clojure.lang.BigInt) |
number with N suffix, or a number too large to fit in a long |
42N, 42000000000000000000 |
Math Operations
TODO: Documentation of math operations, contagion & overflow
Hinting, casting and coercions
TODO: Documentation of autoboxing, type hints on functions, coercion/casting functions
Usage notes
TODO: