DIMINSION ROUNDING 1

[jkelly]

HELLO,

JUST RECENTLY I HAVE BEEN HAVING A PROBLEM WITH THE WAY THAT MY DIMENSIONS ARE ROUNDING. I HAVE MY PRECISION SET TO 0.0 AND TO ROUND OFF TO .5MM. BUT WHEN I DIMINSION IT WILL GIVE ME 1472.5. AND THE ACTUAL DISTANCE IS 1472.8 THUS MEANING IT SHOULD ROUND TO 1473. ANY HELP WOULD BE VERY APPRECIATED.

THANKS IN ADVANCE.
JEREMIAH

 

[Adrian2]

Dear Jeremiah;

I you need to round up or down to the nearest whole number you should set precision to 0 , If you set it to 0.0 you will see 1 digit to the right of the decimal.

Regards

Adrian D.

 

[jkelly]

I NEED TO ROUND TO THE NEAREST HALF A MILLIMETER (.5mm). MAYBE MY EXAMPLE THREW YOU OFF. IT COULD EVEN SAY 375 WHEN THE ACTUALL DISTANCE IS 374.7. AND IT SHOULD ACTUALLY READ 374.5.

 

[m4kert]

Um... jkelly,

I think what you are after is against rules of math.
When rounding UP, 0 through 4 is zero and 5 through 9 increase the next number by 1.
Examples:
123.45 rounded to one place is 123.5
123.44 rounded to one place is 123.4

A previous coworker had the same type of problem with metric to english conversion. He used to use a factor of .04 in his programs. When it is better to use 1/25.4.
In large machines that "rounding up" can create as error so that sub-asseblies won't fit together.

good fortune
m4kert

 

[coppr]

I believe we've been having the same problem. If the dim is .125, SOMETIMES it rounds to .13 and SOMETIMES to .12, both in the same drawing, on the same sheet.

 

[CDH]

Why use rounding at all?
If you draw it the actual correct size, the dimension will read exactly the say you want it to. I don't use metric, but this still applies. I have my drawing units set to 1/256 and my dimension units set the same. When I dimesnion something and it comes out an odd number, then I know that it is drawn wrong.
Rounding is ok for quick fixes, but in the end, the object is wrong. Say you have a string of dimensions that all read 0.5 and but when you measure the true lengths, they are all 0.4. The dimension is rounding to what you think is right, (0.5) but when you try to get an overall it doesn't match the individuals. If you have three in a row you will would expect to get a dimension of 1.5, but in reality since they are all 0.4 the total is 1.2 and when you put the dimesnion on, it rounds down to 1.0
If you have an overall that reads 1.0 and three individuals that read 0.5, there is obviously something wrong.

I would suspect in the case of 1.25 being either .13 or .12, it you would set your units to a higher precision and then get the actual length of the line, they are probably different.

Anyway, sorry for the long post, but I just had to express my opinion on rounding dimensions.