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ice2642

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Joined: 27/05/2023
Location: Brazil
Posts: 82

Posted: 12:00pm 27 Jul 2023

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Hello,

Sorry about my English, I hope you understand what I want to ask.

I would like to know if in the MMbasic << >> is like in C change the binary value for ex 0001 with 2 << wil go to 0100 ?
I do not understand how to use it in Basic.

Can we give me a little example?

Thank you in advanced.

Best Regards,

MMBasic 5.0707 on PicoMite VGA

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1270

Posted: 12:12pm 27 Jul 2023

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<< is Bitshift left ..

as you might see, every Shift left doubles the Value:
the number behind << is the Counter of the "shifts"
0001 << 2 = 1*4 so the you'll get 0100

in Basic it is simply:

a=1
a=a<<2
?a
n=32
n=n>>2
?n

Edited 2023-07-27 22:16 by Martin H.

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ice2642

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Joined: 27/05/2023
Location: Brazil
Posts: 82

Posted: 12:15pm 27 Jul 2023

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Martin H. said << is Bitshift left ..

as you might see, every Shift left doubles the Value:
the number behind << is the Counter of the "shifts"
0001 << 2 = 1*4 so the you'll get 0100

I get,

Thank you.

MMBasic 5.0707 on PicoMite VGA

ice2642

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Joined: 27/05/2023
Location: Brazil
Posts: 82

Posted: 12:50pm 27 Jul 2023

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Have some advantage to use a<<2 instead A^2 in BASIC?

Speed or some like this?

Thank you.

MMBasic 5.0707 on PicoMite VGA

phil99

Guru

Joined: 11/02/2018
Location: Australia
Posts: 2679

Posted: 01:06pm 27 Jul 2023

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Needs fewer clock cycles.

> timer=0:for x=0 to 999999:n=2^8:next:?timer
13733.523
> timer=0:for x=0 to 999999:n=1<<8:next:?timer
12520.537
> timer=0:for x=0 to 999999:n=1:next:?timer
11138.736
>

ice2642

Regular Member

Joined: 27/05/2023
Location: Brazil
Posts: 82

Posted: 01:07pm 27 Jul 2023

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phil99 said Needs fewer clock cycles.

> timer=0:for x=0 to 999999:n=2^8:next:?timer
13733.523
> timer=0:for x=0 to 999999:n=1<<8:next:?timer
12520.537
> timer=0:for x=0 to 999999:n=1:next:?timer
11138.736
>

Cool,

Thank you :)

MMBasic 5.0707 on PicoMite VGA

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