Scaling string representation differs from dividing by 10^x about rust-decimal HOT 4 OPEN

You want the normalize[1] or normalize_assign[2] functions, to strip the extra 0.

[1] https://docs.rs/rust_decimal/latest/rust_decimal/struct.Decimal.html#method.normalize
[2] https://docs.rs/rust_decimal/latest/rust_decimal/struct.Decimal.html#method.normalize_assign

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Ah awesome!

Should the docs of set_scale maybe be adjusted so that future users know about it?

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Thanks @Tony-Samuels for your reply - exactly right.

@Zarathustra2 - I think there is always an opportunity to make the documentation clearer. In this case, would it help to describe what set_scale is doing under the hood? i.e. we maintain the same mantissa, but just change where the decimal point is - hence retaining precision without rounding. e.g. in this example 3850 is having the decimal point moved to the left 3 places.

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@paupino Yes some clearer docs would be nice. Maybe we can also add a code example directly to the docs as example. I personally think a coding example with comments is more clear than plain text.

    let num = 3850;
    let dec = Decimal::from(num) / Decimal::ONE_THOUSAND;
    
    let mut dec_scale = Decimal::from(num);
    dec_scale.set_scale(3).unwrap();
 
    // Passes since same number
    assert_eq!(dec, dec_scale);
    assert_eq!(dec.to_string(), "3.85".to_string());
    // set_scale just moves the decimal point and keeps original mantisse. 
    // this effects the string representation but both dec & dec_scale represent
    // the same number
    assert_eq!(dec_scale.to_string(), "3.850".to_string());
    assert_eq!(dec_scale, dec);
    assert_ne!(dec_scale.to_string(), dec.to_string());
    // Use normalize to normalize the mantisse
    assert_eq!(dec_scale.normalize().to_string(), "3.85".to_string());

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