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Dear Maple Users

I wonder if and how I can use Maple to calculate the difference of two sums algebraically, meaning if I dont have an explicit expression for the range of the sum. Rather, I want to calculate

Sum(i, i=0..N) - Sum(i, i=0..N, i!=k);

which should, obviously return k.

Is it possible to evaluate such an expression, and more advanced cases, using Maple?
Thanks for hints.

 

hi

I have 10 equations and the summation of them will give me the answer but each of them have small numeric noises and the sumation of them makes the final result inaccurate.  For example the first equation is 

How can a vector A=<2,3> be summed to 5.

 

I've been trying to work out an algebraic expression for the following summation

S[n,t] = Sum(factorial(k)/factorial(k+t), k = 0 .. n-1), entered as S[n,t]:=sum(f,k=0..n-1); (with f:=k!/(k+t)!;)

I entered the above Maple expression into Maple (13) just so I could check out some small example summations I had. Maple's arithmetic, accuracy and speed is much superior to mine!...

Given a vector with six elements called, say, c, how do I assign the sum of its values to a name called d without having to write d=c[1]+c[2]...?

Thanks in advance.

Dual sum loop with a condition

March 12 2012 by Ronan 5 Maple

I am new to Maple so apppologies if this is a very basic question. I have a dual sum loop. Sigma i=1to 6(sigma j=1to 6)A_iB_j.

That works fine. I need to include the condition i+j<=8. So when when i=3 j can only count to 5, i=4 j count to 4, i=5 j count to 3. etc.

At present I am just using the work sheet. Haven't got into writing code yet.

 

Would appreciate any assistance,

simplify a summation function

March 09 2012 by dryder 5 Maple

Is there a simple way to have Maple re-formulate an expression like:

  r^2 * sum(A(j)*r^(n+j))

to :

  sum(A(j)*r^(n+j+2)

 

simplity, collect doesn't seem to do it.

Is there a simple function, or does one have to revert to the subsop procesure reported in a 2008 post.

 


Thanks.

Hey guys !

 

I wondered if it's possible in maple to hundle functions, for exemple to know if a function is a sum or a product of two functions.

 

Is there a function like this : sum (\x -> x+3)  -------->  [(\x -> x), \x -> 3] ?

 

If I ask this, is because I want to know if it's possible de rewrite the function `deriv` or `integrate` or `simplify` by hands, without using the native functions.

Let a list of n positive integers be given, e. g. [2,1,4].
Let us consider all sums of  all its members signed by +-, e. g
-2-1-4=-7, -2+1-4=-5, -2-1+4=1, ... .
How to find the sum having the minimum  absolute value with Maple?

why is this sum false?

January 20 2012 by Christopher2222 3229 Maple 12

is(sum( (1+i)(k-1), k = 1 .. 8) = sum( (1+i)(k-1), k = 8 .. 1))
                                                       false

Is that a bug in sum that got fixed in a newer Maple or maybe I missed something?...

help me please !

January 08 2012 by mad_man10 5

hi

i want to write an integer n into all possible sums ,  i found

 Maple readily turns partial sum 1+sum(alpha^2, j = 1 .. l-1) into expression 1+(l-1)*alpha^2. 

I need to replace alpha with a function c(j) such that c(0)=1 and c(j)=alpha for j=1,2,3,...and to compute sum(c(j)^2, j = 0 .. l-1) symbolically to get the above expression. This is the simplest special case only and in general c(j) is 1 for j=0 and some expression involving j and alpha, beta, etc for j::posint.

I tried several thing, e.g., 

Dear Maple Team,

     I found a very strange thing in my Maple 14: When I typed the two command line as follows:sum(n^4, n); expand(sum(i^4, i = 1 .. n)), the results are not the same. Now I copy them here.

                   1  5   1  4   1  3   1  
       ...

 

How may I program the following with Maple?

 

(1) Define the function:

H(p) := p * c1 + p^2 * c2 + p^3 * c3  + ......

 

(2) Now construct the following expression:

 

(1-p) [ v''' + 1 ]  = H(p) [ v''' - 25 * v' + 1]

Here, v is some funciton of x.

 

(3) Now assume: v = u0 + u1 * p + u2 * p^2 + ...

and substitute this into the expression defined at the point (2).

Hello,

 

I am doing some complicated computations in Maple, and I noticed something was wrong. For some reason, Maple makes the sum of 1 a zero, although he knows that it is a 1.

this is the code:

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