I need to convert this to the range of $[0.0, 1.0]$ where $0.5$ corresponds to Nyquist frequency and $1.0$ to sample rate. And I'm trying to figure out the smartest way of doing this and whether I can use a general "any number range to any number range" algorithm or whether the radians/samples unit poses some problems regarding this?
As you noted in your comment, the normalized frequency range
[0, 1) cycles/sample corresponds to the range
[0, 2*pi) radians/sample. Therefore, given a frequency in the
[0, 1) range, simply multiply by
2*pi to convert to radians/sample.