This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English version of the page.

Note: This page has been translated by MathWorks. Click here to see
To view all translated materials including this page, select Country from the country navigator on the bottom of this page.


Base 2 power and scale floating-point numbers


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


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

X = pow2(F,E) computes x = f * 2e 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.


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 


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

Extended Capabilities

See Also

| | | | | |

Introduced before R2006a

Was this topic helpful?