bitwise shift? | Bytes (2024)

desktop

I have found a code example with this loop.

for k in range(10, 25):
n = 1 << k;
I have never read Python before but is it correct that 1 get multiplied
with the numbers 10,11,12,12,... ,25 assuming that 1 << k means "1 shift
left by k" which is the same as multiplying with k.

Apr 25 '07 #1

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10 2574

Michael Hoffman

desktop wrote:

I have found a code example with this loop.
for k in range(10, 25):
n = 1 << k;
I have never read Python before but is it correct that 1 get multiplied
with the numbers 10,11,12,12,... ,25

No.

assuming that 1 << k means "1 shift left by k"

Yes.

which is the same as multiplying with k.

No.

Try starting the Python interpreter and entering 1 << 10.
--
Michael Hoffman

Apr 25 '07 #2

=?ISO-8859-1?Q?Thomas_Kr=FCger?=

desktop schrieb:

I have found a code example with this loop.
for k in range(10, 25):
n = 1 << k;
I have never read Python before but is it correct that 1 get multiplied
with the numbers 10,11,12,12,... ,25 assuming that 1 << k means "1 shift
left by k" which is the same as multiplying with k.

1 << n
is a more efficient replacement for
2**n

Thomas

--
sinature: http://nospam.nowire.org/signature_usenet.png

Apr 25 '07 #3

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