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HP 17Bii LET & GET misunderstanding? - Printable Version

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HP 17Bii LET & GET misunderstanding? - jthole - 12-05-2019 08:01 AM

Probably a rookie mistake on my part, but I don't see why this calculation doesn't work:

MX = L(D:HM-HR)x0,95+HR+0xL(FR:G(D)x0,8+HR)+0xL(WL:G(D)x0,65+HR)+0x(FR+WL)

MX = heart rate threshold
HM = maximum heart rate
HR = resting heart rate
FR = fitness range
WL = weight loss range

When entering HM and HR (179 and 43, in my case) I get the correct value for MX. But when I try to display the value for FR or WL, I get "SOLUTION NOT FOUND".

What am I missing here? Thanks a lot!


RE: HP 17Bii LET & GET misunderstanding? - Dave Britten - 12-05-2019 12:29 PM

(12-05-2019 08:01 AM)jthole Wrote:  Probably a rookie mistake on my part, but I don't see why this calculation doesn't work:

MX = L(D:HM-HR)x0,95+HR+0xL(FR:G(D)x0,8+HR)+0xL(WL:G(D)x0,65+HR)+0x(FR+WL)

MX = heart rate threshold
HM = maximum heart rate
HR = resting heart rate
FR = fitness range
WL = weight loss range

When entering HM and HR (179 and 43, in my case) I get the correct value for MX. But when I try to display the value for FR or WL, I get "SOLUTION NOT FOUND".

What am I missing here? Thanks a lot!

Since FR and WL don't affect the value of the equation (because of 0*L(...)) the 17BII can't really "solve" for them. But since you're setting them using L() as a side effect of solving for MX, you can press RCL FR or RCL WL to retrieve those values after solving for MX.


RE: HP 17Bii LET & GET misunderstanding? - jthole - 12-05-2019 12:49 PM

(12-05-2019 12:29 PM)Dave Britten Wrote:  Since FR and WL don't affect the value of the equation (because of 0*L(...)) the 17BII can't really "solve" for them. But since you're setting them using L() as a side effect of solving for MX, you can press RCL FR or RCL WL to retrieve those values after solving for MX.

Thanks!!