Calculate share of Nats

Developers
1

Let’s say I have two Nats: A and B
By definition A is always bigger than B

How can I calculate X: float32 which is B / A?

2

Motoko doesn’t have float32, only Float, which is 64-bit.

import Float "mo:base/Float";
Float.fromInt(B) / Float.fromInt(A)

fromInt works for Nat, because Nat is a subtype of Int.

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3

Yea… sorry for misleading. I’m looking for a rust solution.

Thanks for your answer!

4

Will something like this work?

use num_traits::ToPrimitive;
...
result.0.to_f32();

UPD: no it won’t :frowning:

5

I’ve figured out your example won’t work also if A and B are both bigger than 64 bits.

6

Yes, but since you are losing precision anyway, you can truncate Nat to 64 bits before converting to Float.

For Rust, you may need infinite precision fraction as well, for example fraction - Rust

You can also decode a Candid Nat to u128 in Rust (decoding will fail if the value is more than 128bit). Might be easier to convert u128 to f32.

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