pow2 - Base 2 power and scale floating-point numbers

Syntax

X = pow2(Y)
X = pow2(F,E)

Description

X = pow2(Y) returns an array X whose elements are 2 raised to the power Y.

X = pow2(F,E) computes for corresponding elements of F and E. The result is computed quickly by simply adding E to the floating-point exponent of F. Arguments F and E are real and integer arrays, respectively.

Remarks

This function corresponds to the ANSI C function ldexp() and the IEEE floating-point standard function scalbn().

Examples

For IEEE arithmetic, the statement X = pow2(F,E) yields the values:

    F         E        X
    1/2       1        1
    pi/4      2        pi
    -3/4      2        -3
    1/2       -51      eps
    1-eps/2   1024     realmax
    1/2       -1021    realmin 

See Also

log2, exp, hex2num, realmax, realmin

The arithmetic operators ^ and .^

  


 © 1984-2008- The MathWorks, Inc.    -   Site Help   -   Patents   -   Trademarks   -   Privacy Policy   -   Preventing Piracy   -   RSS