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Fix misleading statement regarding sign bit #260

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Fix misleading statement regarding sign bit #260

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10 changes: 5 additions & 5 deletions README.md
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Expand Up @@ -31,11 +31,11 @@ For `T<:Signed` (a signed integer), there is a fixed-point type
`Normed{T, f}` type. However, there are slight differences in behavior
that go beyond signed/unsigned distinctions.

The `Fixed{T,f}` types use 1 bit for sign, and `f` bits to represent
the fraction. For example, `Fixed{Int8,7}` uses 7 bits (all bits
except the sign bit) for the fractional part. The value of the number
is interpreted as if the integer representation has been divided by
`2^f`. Consequently, `Fixed{Int8,7}` numbers `x` satisfy
The `Fixed{T,f}` types take the integer type `T` and simply shift the "decimal"
point (or more accurately, the [radix or binary
point](https://en.wikipedia.org/wiki/Decimal_separator#Radix_point)) `f` bits to
the left, i.e. they represent real numbers of the form `x::T / 2^f`.
Consequently, `Fixed{Int8,7}` numbers `x` satisfy

```julia
-1.0 = -128/128 ≤ x ≤ 127/128 ≈ 0.992.
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