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An extract from A Program for Determining Cocompost Blending Ratios, Compost Science & Utilization (magazine), Summer 1993, pages 30-33

A program is presented that computes blending ratios for two ingredients of a cocompost. The program is written in the RPN language, requires 61 lines of memory, and will support hand-held programmable calculators, making it suitable for use in the field. Use of this program allows the composter to determine blending ratios quickly and with increased precision and accuracy.

… designed to be entered on the Hewlett-Packard HP 32SII programmable calculator but with minor transcriptional changes, will work on calculators made by other manufacturers. The program is entered on the calculator and will be stored, even after the calculator is turned off, and the program will not interfere with other calculator functions.
The program is listed on Table 3 …

TABLE 3. A program to compute co-compost blending ratios to achieve a specified CN and a specified moisture level, in the RPN language, for use on the Hewlett-Packard HP 32SII programmable calculator …

BEST!
SlideRule
(12-27-2019 12:06 PM)SlideRule Wrote: [ -> ]...but with minor transcriptional changes, will work on calculators made by other manufacturers.

How many other manufacturers made RPN programmables at the same time as the 32Sii I wonder. The program is one long formula, converting to algebraic isn't a minor change

Pauli
(12-27-2019 12:06 PM)SlideRule Wrote: [ -> ]An extract from A Program for Determining Cocompost Blending Ratios ...

Sample calculation example (p 32), we have carbon/nitrogen ratio:

$$\large {c \over n} = \frac{b_c\,+\,a_c S}{b_n\,+\,a_n S} = \frac{33.6\%\,+\,(50.4\%)S}{5.6\%\, + \,(0.09\%)S}$$ ﻿ ﻿ ﻿ ﻿ , S = weight ratio A/B

The article says c/n = 30, S = 0.805, which is way off.
Try above formula, for S = 0.805, we only get c/n ≈ 13.08

Correct value for c/n = 30 should be S ≈ 2.818

I have not read actual code, but if its own example is wrong ...
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