Inventor General Discussion

Inventor General Discussion

Reply
Distinguished Contributor
eveylynne
Posts: 118
Registered: ‎12-16-2011
Message 1 of 7 (993 Views)

Square root confusion

993 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.

Distinguished Contributor
eveylynne
Posts: 118
Registered: ‎12-16-2011
Message 2 of 7 (990 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.

*Expert Elite*
mrattray
Posts: 2,501
Registered: ‎09-13-2011
Message 3 of 7 (988 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

*Expert Elite*
JDMather
Posts: 26,865
Registered: ‎04-20-2006
Message 4 of 7 (978 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.
-----------------------------------------------------------------------------------------
Autodesk Inventor 2014 Certified Professional
Autodesk AutoCAD 2013 Certified Professional
Certified SolidWorks Professional
Inventor Professional 2015 64-bit
http://www.autodesk.com/edcommunity
http://home.pct.edu/~jmather/content/DSG322/inventor_surface_tutorials.htm
*Pro
ampster
Posts: 1,271
Registered: ‎07-26-2005
Message 5 of 7 (976 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...

Distinguished Contributor
eveylynne
Posts: 118
Registered: ‎12-16-2011
Message 6 of 7 (969 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.  

*Expert Elite*
JDMather
Posts: 26,865
Registered: ‎04-20-2006
Message 7 of 7 (963 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.

 

Units Conversion.png

 

 

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.
-----------------------------------------------------------------------------------------
Autodesk Inventor 2014 Certified Professional
Autodesk AutoCAD 2013 Certified Professional
Certified SolidWorks Professional
Inventor Professional 2015 64-bit
http://www.autodesk.com/edcommunity
http://home.pct.edu/~jmather/content/DSG322/inventor_surface_tutorials.htm
Announcements
Are you familiar with the Autodesk Expert Elites? The Expert Elite program is made up of customers that help other customers by sharing knowledge and exemplifying an engaging style of collaboration. To learn more, please visit our Expert Elite website.
Need installation help?

Start with some of our most frequented solutions or visit the Installation and Licensing Forum to get help installing your software.