# Float64 > Base utilities for double-precision floating-point numbers.
## Usage ```javascript var ns = require( '@stdlib/number/float64/base' ); ``` #### ns Base utilities for double-precision floating-point numbers. ```javascript var o = ns; // returns {...} ```
- [`exponent( x )`][@stdlib/number/float64/base/exponent]: return an integer corresponding to the unbiased exponent of a double-precision floating-point number. - [`fromBinaryString( bstr )`][@stdlib/number/float64/base/from-binary-string]: create a double-precision floating-point number from a literal bit representation. - [`fromInt64Bytes( bytes, stride, offset )`][@stdlib/number/float64/base/from-int64-bytes]: convert a signed 64-bit integer byte array to a double-precision floating-point number. - [`fromWords( high, low )`][@stdlib/number/float64/base/from-words]: create a double-precision floating-point number from a higher order word and a lower order word. - [`getHighWord( x )`][@stdlib/number/float64/base/get-high-word]: return an unsigned 32-bit integer corresponding to the more significant 32 bits of a double-precision floating-point number. - [`getLowWord( x )`][@stdlib/number/float64/base/get-low-word]: return an unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number. - [`normalize( [out,] x )`][@stdlib/number/float64/base/normalize]: return a normal number `y` and exponent `exp` satisfying `x = y * 2^exp`. - [`setHighWord( x, high )`][@stdlib/number/float64/base/set-high-word]: set the more significant 32 bits of a double-precision floating-point number. - [`setLowWord( x, low )`][@stdlib/number/float64/base/set-low-word]: set the less significant 32 bits of a double-precision floating-point number. - [`signbit( x )`][@stdlib/number/float64/base/signbit]: return a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false). - [`toBinaryString( x )`][@stdlib/number/float64/base/to-binary-string]: return a string giving the literal bit representation of a double-precision floating-point number. - [`float64ToFloat32( x )`][@stdlib/number/float64/base/to-float32]: convert a double-precision floating-point number to the nearest single-precision floating-point number. - [`float64ToInt32( x )`][@stdlib/number/float64/base/to-int32]: convert a double-precision floating-point number to a signed 32-bit integer. - [`float64ToInt64Bytes( x )`][@stdlib/number/float64/base/to-int64-bytes]: convert an integer-valued double-precision floating-point number to a signed 64-bit integer byte array according to host byte order (endianness). - [`float64ToUint32( x )`][@stdlib/number/float64/base/to-uint32]: convert a double-precision floating-point number to an unsigned 32-bit integer. - [`toWords( [out,] x )`][@stdlib/number/float64/base/to-words]: split a double-precision floating-point number into a higher order word and a lower order word.
## Examples ```javascript var objectKeys = require( '@stdlib/utils/keys' ); var ns = require( '@stdlib/number/float64/base' ); console.log( objectKeys( ns ) ); ```