Aspect ratio definitions

[vedina]

There are four entries defining aspect ratio in enanomapper ontology

under dimensionless unit , without definition

• NPO_1365

under image analysis descriptors , with conflicting definitions:

• ENM_8000064 - as defined in ImageJ , Major axis/Minor axis (which gives values >1)
• ENM_8000033 as defined in a publication , Aspect ratio X, defined as AR_x=dmin_x/max_y,
• ENM_8000034 as defined in a publication; Aspect ratio Y, defined as AR_y=dmin_y/max_x

The publication cited is doi:10.3109/17435390.2014.930195 , where I could not find aspect ratio definition (or even aspect ratio in the data tables). It cites doi:10.1016/j.biomaterials.2010.06.051 with reports aspect ratios values > 1 , also could not find a definition.

• where the formulas in ENM_8000033 & ENM_8000034 come from ?

• there is indeed ISO 9276 aspect ratio definition (for not very elongated particles) xFeret-min/xFeret-max , but it is not included in ENM ontology