(50g) Convert Approximate to Exact for given argument

[johnb]

(08-02-2021 12:28 AM)DavidM Wrote:  As a result, I am occasionally frustrated that I've inadvertently changed a program, list, algebraic or other object into something containing approximate numbers (reals), when it was originally intended to have contained integers.

Sorry I am so late to this party, but hopefully someone will find the following advice useful.

Having been a heavy user of an HP-48g the past couple years, I've been frustrated with accidentally clobbering a program or variable here and there. I've learned a trick:

• Global variables and programs go in {home}
• "Package" scoped variables and programs and such go in {home}/{topic}
• Do your work in {home}/{topic}/{work}
  

(Legend: above, underlined are literal directory names, placeholder for names are in italic.)

Topics are general packages of components. For example, I might have topics "CS", "NUMR" (numerical recipes/solutions), "INTV" (interval arithmetic), "PROJ1" and "PROJ2" (two short-term work projects).

By always working in a {work} directory, I can accidently override a global or package variable with one of my own... but I cannot accidentally overwrite one, permanently clobbering it. I just purge the offending item from {work} and try again.

And then, it's also easy to clean up after myself. I can safely purge the entire contents of my "workspace" without clobbering any of the components I'll be wanting to use there for next time.

This strategy should work for all RPL calculator series: 28, 48, 49 (all variants), and 50.


Hope this helps!