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[WP34S] A funny bug in Pi (prod) - Printable Version

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[WP34S] A funny bug in Pi (prod) - Eduardo Duenez - 01-27-2013

Hi,

I was using my 34S flashed to recent 3350 calc-full.bin

I had never used the sum (Sigma) and product (Pi) functions.

I coded the identity function f(x)=x trivially:

LBL B

RTN

Then I tried adding 1+2+...+10 with Sigma:

1

[ENTER]

10

[SIGMA]

B

Output: 55 (correct).

Then tried to find 10! instead

1

[ENTER]

10

[PI]

B
Output: 0 (should be 10!=3628800)

There is a funny bug in the implementation of PI (product), but not in SIGMA.

Cheers,

Eduardo

Re: [WP34S] A funny bug in Pi (prod) - Paul Dale - 01-28-2013

Both of these functions take one argument from the stack which is a loop index for the DSL instruction. In both cases you are summing/multiplying from 0 to 10 not 1 to 10.

You want 10.001 {PI} B.


- Pauli

Re: [WP34S] A funny bug in Pi (prod) - Walter B - 01-28-2013

Compare p. 112 of the manual.

d:-)

Re: [WP34S] A funny bug in Pi (prod) - Eduardo Duenez - 01-28-2013

My bad. RTFM!

Thanks,
Eduardo

Quote:
You want 10.001 {PI} B.

- Pauli