 # Converting units

When calculated with below:
`mm3 = 20.000.000`
`m3` results in `0`
further calculations with `m3` result in `0` as well

we work with `mm`
but supplier delivers in cubic meters
we need to convert from `mm^3` to `m^3` for our calculations

``````'m3'
= 'mm3' * 1 * 10 ^ -9
@numerical-type: (
label: "m3"
decimals: 3
)
``````

Welcome to the forum!

I am not entirely sure what your question is, but I think the explanation below may help.

For converting `20.000.000 mm^3` to `m^3`, you have to multiply with `1 * 10 ^ -9`, which gives `0.02 m^3`. The application engine rounds to the nearest whole number, so the result of the conversion is and should be `0`.

Alan only stores whole numbers. If you need an accuracy of `mm^3` for your computations, then that is the numerical type you should start with. If the supplier provides values in `m^3`, you should convert them to `mm^3` with the conversion rule `= 'm3'...` shown below.

If you want to show `mm^3` as `m^3` in your application, you can use the `@numerical-type:` GUI annotation as shown below. Please note that GUI annotations only affect how values are presented to the application user. They do not in any way affect calculations.

``````'mm3'
= 'm3'* 1 * 10 ^ 9 // conversion rule for converting 'm3' to 'mm3'
@numerical-type: ( // show mm3 as m3 in the ui, by moving the decimal point 9 places to the left
label: 'm3'
decimals: 9
)
``````

thanks, the moving decimals was what I’ve overlooked.