Summation with begin or end index as an expression doesn't work.

[MohamedE]

Indeed, when executing Sum[k,{k,1,n+1}], the result was Sum(k,{k,1,n+1}).

A good reference:

http://www.wolframalpha.com/input/?i=sum[i]+with+i+from+a+to+b

[Axel Kramer]

Fixed with this commit https://bitbucket.org/axelclk/symja_android_library/commits/496d52caa458da94890be3cca58dd7cc4dba59d4

[MohamedE]

Will you put a new downloadable .jar?

[MohamedE]

Thanks for your reactivity.

However, this case Sum[k * k,{k,1,n+1}] doesn't work.

[MohamedE]

In addition, I tried Sum[k,{k,0,n-1}], I obtained n(-1 + n) /2, which is not ergonomically nice to look at. Don't you agree?

[MohamedE]

The obtained result I am talking about above n(-1 + n) / 2 is at the level of LaTeX.

[MohamedE]

Result with LaTex isn't ergonomic enough.

[Axel Kramer]

Fixed issue46 case "Sum[k * k,{k,1,n+1}]"

→ <<cset 4733f909e9d0>>

[MohamedE]

This expression works just fine: Sum[(i^2 + i)/2, {i,1,n}].

However, this one Sum[i(i + 1)/2, {i,1,n}], doesn't work at all.

[Axel Kramer]

Fix issue46 Sum[i(i + 1)/2, {i,1,n}]

→ <<cset f6a36cd84e12>>

[MohamedE]

Could you prepare the .jar file, please?

[MohamedE]

Formula with composite begin index doesn't work:

Sum[1,{k,j+i,n}]

[Axel Kramer]

Fix issue46: Formula with composite begin index doesn't work: Sum[1,{k,j+i,n}]

→ <<cset b48b67183258>>

[MohamedE]

This formula won't work:

Sum[Sum[placeholder, {j,i,n-1}], {i,1,n-1}]

But it works for this one:

Sum[Sum[c, {j,1,n}], {i,1,n}]

[Axel Kramer]

I uploaded a new version.

Please try this notation:

Sum[placeholder, {j,i,n-1}, {i,1,n-1}]

[MohamedE]

Indeed, it's working better, even with the recursive notation Sum[Sum[]].

However, there's a specific case that doesn't work (with '*' symbol):

Sum[Sum[c*(i-j+1), {j,i+1,n}], {i,1,n}]

[Axel Kramer]

Fix issue46

→ <<cset b21f37970cbd>>

[MohamedE]

Did you test it with division (just out of curiosty)?

Sum[Sum[c/(i-j+1), {j,i+1,n}], {i,1,n}]

It seems like it doesn't work.