Just out of curiosity. I have touched on this subject before. I have to report a Profile back to itself. I normally report it Least Square. I chose Vector Least Square and it came out better. What is difference on this setting actually than that of Least Square? From my understanding it is a result of better actual hits taken.
Profile of sphere
Collapse
X

Profile of sphere
Last edited by KIRBSTER269; 02142017, 01:48 PM.(In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)They say "Nobody's Perfect." I must be Nobody.Tags: None

 Least Squares (default)  minimizes the average squared error of the fit among all of the features included in the best fit. This is the most common best fit type. The error value is the sum of the squared distances. Outliers don't have as bad an effect and direction of error plays no role in this fit.
 Vector (also known as Projected Least Squares)  also minimizes the average squared error among the features being fit; however, it first snaps (or projects) the points back onto the nominal vectors of the feature. Therefore, all error will be along the nominal vectors. The error value is the sum of the squared projected distances. This type of fit is typically used when a set of points is being fit to curves and / or surfaces. With this type of fit, PCDMIS allows points to 'slide' along the surface but discourages them from pulling away from the surface.
Example: If the Nominal point is: 1.1.1 with the vector: 0,0,1, and Measure values 4,2,0.95, then the measured data will be adjusted to 1,1,0.95, snapped to the vector of 0,0,1.
Correction I have been using Vector Least square.(In Memory of my Loving wife, "Ronda" who I lost March 7, 2016. I love you baby.)They say "Nobody's Perfect." I must be Nobody.

have you tried using vector least square? (kidding) in addition, there is vector min max in newer versions, but TP forum was closed before I could ask Rob why I got such a big difference in profile between
vector LS and vector min max. Perhaps a guru can shine some light?
 Likes 1
Comment

I'm not at my machine but if I remember correctly the help files say that the least square is generally for planar features whereas the vector least square is for non flat features. I'll check when I get in tomorrow if I haven't been corrected or confirmed by then.
 Likes 1
Comment

That's what I copied out of the help file on the 2nd post. 4th sentence in the vector part, states, for curved surfaces.

That's quite alright william .I still expect you to throw your 2 cents in. I want as much feedback as I can. Makes me a little more sure of myself.
Related Topics
Collapse

by gdntnoviceCan someone provide me with the solve importer and explain me in plain English how does it works. I need to know all the equations and the logic behind...

Channel: PCDMIS for CMMs
04202020, 11:35 PM 

by ParkerWhich is the better BestFit alignment to use when comparing point deviation to CAD models? (Least Squares or Vector) Example, I am measuring these 36...

Channel: PCDMIS for CMMs
02192020, 12:31 PM 

by Mike N.could someone be more descriptive in explaining the differences between using "least squares", "vector","min/max" best fit...

Channel: PCDMIS for CMMs
03012010, 09:53 AM 

by rbexplorerHello, everybody!
I'm student and I have learnt to work with PCDMIS and CMM DEA. I have one question... What does bestfit alignment mean?...
Channel: PCDMIS for CMMs
02062009, 05:02 AM 

by SALTYFRIESI've been measuring some 3D contoured surfaces on gages and the customer has expressed an interest in loosening tolerances to make the gages easier to...

Channel: PCDMIS for CMMs
02102015, 08:22 PM 
Comment