HP 11C real root finder [Newton Method]

[Dieter]

Namir, sorry that I was not able to express myself clearly. I wanted to point out that I do not think it's a good idea to use h = 0,01 or 0,001 for any value below 1. This may lead to significant errors since h may be much, much larger than x. For instance, if x = 1E-10, h = 1E-3 is not recommended. Here, h = 1E-13 should be better.

That's why I prefer to set h = 0,001 x or similar. With the only exception x=0 where x may be 0,001.

(01-15-2014 05:53 AM)Namir Wrote:  Until I realized one day that .01*(|x|+1) does the job and eliminates the need for labels and GOTOs. I recently started using .001 instead of 0.01. Using the expression for h ensures that if x=0, h is not zero.

This can be coded this way, for instance:

Code:

 X=0?
 e^x
 EEX
  3
  /

Look, no labels or gotos required. ;-)

Or even more elegant on the 34s:

Code:

 X=0?
 INC X
 SDR 3
 RSD 1   ' optional

Dieter