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help with significant figure function

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Join Date: Sep 2004

Posts: 13

Reputation: potential is an unknown quantity at this point

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potential

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help with significant figure function

Dec 3rd, 2004

guys, i need your help. please...

i need to make a function which compares 2 values if they are equal up to 1,2,3,4,5 significant figures.

it needs 3 parameters: x1, x2 (the values to be compared) and sf (the # of sign. figures)

i think i need to subtract x1 and x2 and divide it with a number...

please help me... please give me tips or something...i really really tried, but i still can't successfully figure out what to do...

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Join Date: Jun 2004

Posts: 436

Reputation: Chainsaw is an unknown quantity at this point

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Chainsaw

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Re: help with significant figure function

Dec 4th, 2004

you mean like:

1.2345
1.2344

is the same to 3 figures?

So, couldn't you say

int intX1 = (int)(x1 * figures);
int intX2 = (int)(x2 * figures);

if (intX1 == intX2) <same>

where figures is 10 for 1 place, 100 for 2 places, 1000 for three and so on?

This would work to about 9 total digits, but similar methods could give you more.