MATLAB Function Reference

bitmax

Return maximum double-precision floating-point integer

Syntax

• bitmax
  

Description

bitmax returns the maximum unsigned double-precision floating-point integer for your computer. It is the value when all bits are set, namely the value .

Note    Instead of integer-valued double-precision variables, use unsigned integers for bit manipulations and replace bitmax with intmax.

Examples

Display in different formats the largest floating point integer and the largest 32 bit unsigned integer:

• format long e
  bitmax
  ans =
     9.007199254740991e+015
  
  intmax('uint32')
  ans =
     4294967295
  
  format hex
  bitmax
  ans =
     433fffffffffffff
  
  intmax('uint32')
  ans =
     ffffffff
  

In the second bitmax statement, the last 13 hex digits of bitmax are f, corresponding to 52 1's (all 1's) in the mantissa of the binary representation. The first 3 hex digits correspond to the sign bit 0 and the 11 bit biased exponent 10000110011 in binary (1075 in decimal), and the actual exponent is (1075-1023) = 52. Thus the binary value of bitmax is 1.111...111 x 2^52 with 52 trailing 1's, or 2^53-1.

See Also

bitand, bitcmp, bitget, bitor, bitset, bitshift, bitxor

bitget

bitor

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