Is Using Boolean Arithmetic Like This a Good Programming Practice?

The only plausible justification would be a very specific performance requirement, such as deliberately avoiding branches. Even then, measure it first: a compiler may already optimize a readable conditional version, and this expression could introduce other problems or type conversions. Without profiling data, clarity is the better choice.

This is technically possible in some languages, but it is much harder to understand than an `if`/`else` chain or a `switch` statement. Code should primarily be written for the people who will read and maintain it, not just for the computer. Most code reviews would reject this unless there were an unusually strong reason to use it.

Boolean expressions themselves are useful, especially when combined with Boolean operators. Treating their true and false results as numeric exponents or multipliers is a different matter and is generally poor style here. Also, this is an assignment or expression rather than an equation, since `=` usually assigns a value in programming languages.

A conditional structure would make the intent obvious: if the mode is input, do one thing; if it is the hard-coded formula, do another; and if it is skip, avoid the calculation. Once one condition matches, checking the other alternatives through arithmetic expressions is unnecessary and makes the logic look more complicated than it is.