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Topic: How do you get Matlab to recognize 1000 digit numbers without

Replies: 2   Last Post: Jan 7, 2013 10:31 AM

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Steven Lord

Posts: 18,038
Registered: 12/7/04
Re: How do you get Matlab to recognize 1000 digit numbers without rounding?
Posted: Jan 7, 2013 10:31 AM
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"Allen " <> wrote in message
> I am working on project Euler and one of the problems asks you to find the
> largest product of 5 consecutive numbers in a given 1000 digit number. My
> question is how do I input this number without Matlab rounding?

No 1000-digit number can be represented as a finite double precision value
(unless the first 700ish digits are 0.) They will all overflow to Inf
or -Inf. Use Symbolic Math Toolbox instead.

a = sym('123456789012345678901234567890')

Note that the quotes are NECESSARY otherwise MATLAB will interpret your
string of 1000 digits as a double then convert the resulting Inf into a
symbolic object.

Steve Lord
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