Inventor General Discussion

## Inventor General Discussion

Distinguished Contributor
Posts: 146
Registered: ‎12-16-2011
Message 1 of 7 (1,138 Views)

# Square root confusion

1138 Views, 6 Replies
04-25-2012 01:05 PM

I want a dimension to be the square root of 32, so I entered:

Sort(32 LU)

Now, the square root of 32=5.656854...

But the dimension I get is 2.227...

So, I try to play with the numbers a little to decipher what Inventor is doing.  If I enter:

Sort(32 LU)*2

I get 11.314...

2.227*2 does not equal 11.314

However,

(√32)*2=11.313708...

This is the first time I have used equations that are more complicated than basic math. I am confused and would like some insight.

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Posts: 146
Registered: ‎12-16-2011
Message 2 of 7 (1,135 Views)

# Re: Square root confusion

04-25-2012 01:08 PM in reply to: eveylynne

I also wrote the dim as 32^(1/2) and had the same issue.

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Posts: 2,538
Registered: ‎09-13-2011
Message 3 of 7 (1,133 Views)

# Re: Square root confusion

04-25-2012 01:12 PM in reply to: eveylynne

I suspect IV is converting units on you. I don't know what an LU is or what unit you're trying to use but when I type in sqrt(32) invnetor changes it from in to ul and gives me 2.227. If I type sqrt(32 in) I get 3.549 (and an error). If I put sqrt(32 in^2) I get 3.656 (and no error).

I sugest you use iLogic for complex equations.

Mike (not Matt) Rattray

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Posts: 28,228
Registered: ‎04-20-2006
Message 4 of 7 (1,123 Views)

# Re: Square root confusion

04-25-2012 01:16 PM in reply to: eveylynne

Sort(32 LU)  huh?

Maybe this is a language thing, but I think you meant sqrt(32ul)*1mm = 5.657mm

Can you attach the file here?

Please mark this response as "Accept as Solution" if it answers your question.
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Message 5 of 7 (1,121 Views)

# Re: Square root confusion

04-25-2012 01:19 PM in reply to: eveylynne

sorry I can't provide the exact answer you are looking for (or rather how to use it in this case), but if you were to multiply 2.227 X 2.54, you are near the 5.65....

Inventor does something to calcs and assumes all input data is centimeters (cm) IRC.

While this doesn't tell you exactly what you will need to do, hopefully utilizing 2.54 will help in some way...

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Posts: 146
Registered: ‎12-16-2011
Message 6 of 7 (1,114 Views)

# Re: Square root confusion

04-25-2012 01:23 PM in reply to: mrattray

mrattray wrote:

I suspect IV is converting units on you. I don't know what an LU is or what unit you're trying to use but when I type in sqrt(32) invnetor changes it from in to ul and gives me 2.227. If I type sqrt(32 in) I get 3.549 (and an error). If I put sqrt(32 in^2) I get 3.656 (and no error).

I sugest you use iLogic for complex equations.

I made an uber typo in my post. It was supposed to read:

sqrt(32 ul)

Regardless, you're getting the same result (2.227) that I am, and I don't understand where that solution comes from.  The square root of 32 doesn't equal 2.227, it's 5.65685...

I'm just doing some basic geometry for a single part, and I don't understand why IV is giving me the solution it is.

Whatever unit IV is working in, the math shouldn't change.

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Posts: 28,228
Registered: ‎04-20-2006
Message 7 of 7 (1,108 Views)

# Re: Square root confusion

04-25-2012 01:32 PM in reply to: eveylynne

Double click on the formulas for this one.

The document units are inches - the forumula is cm.

The conversion is correct.

Make sure you start from the correct template and make sure of your units.

Please mark this response as "Accept as Solution" if it answers your question.
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