Hi Asuku,

Just a guess: perhaps 10.125 is seen internally as 1.0125 E-1, thus rounded to 1.013 E-1 = 10.13.

To add to Sean’s answer, the Editors tab also has a setting for this, controlling the display in the editors, while the General controls other displays. These are both strictly for display, and the actual value is stored in full floating resolution.

To complement @Kevin Scales reply, if one manually types: 1.23456789 in the X-Half Width aperture field of a surface, it might display as 1.23 (depending on the display settings):

But if we use the ZOSAPI to print the actual X-Half Width value with this line of code (Python):

print(TheSystem.LDE.GetSurfaceAt(1).ApertureData.CurrentTypeSettings._S_RectangularAperture.XHalfWidth)

The result is:

1.23456789

Take care,

David

Just one small point. OS stores all ray and lens system data to 64-bit precison, and all the ‘significant digit’ stuff does is set the formatting of the number when it’s printed in the LDE or some other place. There’s no rounding of the data used in the calculations, just in what is displayed in a text string that represents the value of a double-precision float. 

Edit: Oops, Kevin already said that in fewer words 😎