Editing fixpoint scaling of coefficients doesn't automatically update W and scale - Githubissues

chipmuenk / pyfda

Python Filter Design Analysis Tool

http://chipmuenk.github.io/

MIT License

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Editing fixpoint scaling of coefficients doesn't automatically update W and scale #177

Closed chipmuenk closed 3 years ago

chipmuenk commented 4 years ago

When coefficients are displayed with fixpoint scaling, the scale factor is calculated automatically using scale = 2**WI. The Real-World Value (RWV) is calculated by dividing the fixpoint value by scale. This works for the modes "integer" (WF = 0) and "normalized fractional" (WI = 0) but not for "fractional":

Updating WI doesnt change scale (should it? At least, the user should be able to edit scale manually in this mode)
- Updating WI also doesn't update total word length, this is definitely a bug.

chipmuenk commented 3 years ago

Integrating into #189.