Force scientific notation in Blender GUI I have an addon in development, and create various meshes in it. I have several physically based parameters, that are often extremely small, but make sense in the context they are. I have in my GUI class, for example:
poly_0: FloatProperty(
        name=&quot;POLY_0&quot;,
        description=&quot;Some description...&quot;,
        default=1.26587922531743e-16,
        min=-1000.0,
        max=+1000.0,
        )

In the GUI, I would like to force this Float member to always be displayed in scientific notation, and always with some set precision (number of digits). Looking in the API docs, I cant seem to find this option.
Make a Scientific Notation Property Group.
As a workaround could set up a property group to handle scientific notation. Restricted to the significant digits of the float property, but allows to set the the power.
import bpy
from bpy.props import FloatProperty, IntProperty, PointerProperty
from bpy.types import PropertyGroup


class ScientificNotation(PropertyGroup):
    def get_num(self):
        return self.number *  pow(10, self.power)
    number : FloatProperty(min=-10, max=10)
    power : IntProperty()
    value = property(get_num)

bpy.utils.register_class(ScientificNotation)
bpy.types.Scene.foo = PointerProperty(type=ScientificNotation)

Layout with both number and power to set. Use the value property in calculation.  Could use a string property for the number, to get more sig digits.

Example of use in python console.
&gt;&gt;&gt; C.scene.foo.number = 6.62607004
&gt;&gt;&gt; C.scene.foo.power = -34
&gt;&gt;&gt; C.scene.foo.value
6.626070022583007e-34

See also  https://blender.stackexchange.com/a/134310/15543