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Hello everyone, is there a way to make a summation in such a way that

'\GS(N=1,5,XN)' = 'X1+X2+X3+X4+X5' ?

Simone
(06-03-2016 12:47 PM)Simone Cerica Wrote: [ -> ]Hello everyone, is there a way to make a summation in such a way that

'\GS(N=1,5,XN)' = 'X1+X2+X3+X4+X5' ?

Simone

Your post is not clear enough, but if you want 50g build an expression 'X1+X2+X3+X4+X5' instead of counting the sum, I'm afraid there is no such a function buit in, but it should be easy to write a program using the concatenation of strings, that is "+".
Or is that the sum,of a list?
(06-03-2016 12:47 PM)Simone Cerica Wrote: [ -> ]Hello everyone, is there a way to make a summation in such a way that

'\GS(N=1,5,XN)' = 'X1+X2+X3+X4+X5' ?

Simone

How about this way?

Code:
``` << -> N V  << 1 N FOR K  'V' RCL  ->STR TAIL HEAD K + STR-> NEXT WHILE N 1 > REPEAT + 'N' DECR DROP END >> >>```

Store it in let's say XSUM, then:
'XSUM(5,X)' EVAL will produce what you want. It's limited to single-letter identifiers (by using TAIL HEAD, this can be improved).
Another improvement could be a start value for N, but you get the idea.

Quick footnote: For those trying this in newRPL, the TAIL HEAD combination needs to be removed, as the identifiers in symbolics are unquoted, then the code is good for arbitrary length identifiers.
(06-03-2016 05:20 PM)Claudio L. Wrote: [ -> ]'XSUM(5,X)' EVAL will produce what you want. It's limited to single-letter identifiers (by using TAIL HEAD, this can be improved).
Another improvement could be a start value for N, but you get the idea.

It was just what I wanted,

grazie Claudio.
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