I played around with acers procedure (evalhf) and it so far works quite good. but i received a "FAIL" whenever I add some non-linearities, e.g.

 return sqrt(x)*(1 - add(binomial(_n, k)*(1/10*x - _t/10 + 1/2)^k*
        (1/2 - 1/10*x + _t/10)^(_n - k), k = 0 .. ceil(10 - 1/5*x) - 2));

any thoughts on this?

I use plot('numericIntegral', a..b)

and change the interval [a,b] and zoom in until i am sufficiently closed. I hope that this will work for all interesting cases.

 

I think  there are some difficulties when n is small (e.g.n=7), which are unfortunately the cases that are interesting to me (i.e. n<10).

how do i plot the numericIntegral for different values of t on the x-axis, so that we can observe the intersection of this function with the x-axis? A 2-digit solution (also a graphical one) would be sufficient for my purpose...

ok, i will look over this now ;).

And yes you are right, i mean ceil(10-x/5)=10+ceil(-x/5)

 

 

Hey Erik,

so far it works out quite fine, BUT if i play around with some parameters (e.g. the function within the ceil(...) expression), Maple returns after some computation

fsolve(numericIntegral(r),r)

instead of a value. Do you have an idea how to solve this?

 

Thanks

Qin

Hey Erik,

thanks for your answer. I will try it to see if this solves my problem.

i am only interested in a numeric solution for the null of this equation.

 

best regards

 

QIN

hmm, ok actually the problem is not to assume a concrete value for ceilz but the ceiling function, such that the problem can be written as integral:=int(x*(1-sum(binomial(n,k)*[(x-t+5)/10]^k*[1-[(x-t+5)/10]]^(n-k), k=0..ceil(10-x/5)-2)),x=t-5..t+5); where the sum now goes from k=0 to the round-up of the function f(x)=10-0.2*x which is evaluated for each x through the integral and when the ceiling is evaluated for a given x the value 2 is subtracted. I now want to know for what value of t is this equation equal to zero? but i cannot solve this in maple :( hope this makes my problem clear... Regards QIN

hmm... nobody got an idea about it?

any help is highly appreciated ;)

not a single idea, anyone?

 

:(

Hey Robert,

Indeed i did not differentiate x and X. sorry for that.

Specifically i came over a reading in my literature list (http://www.rieb.kobe-u.ac.jp/academic/ra/seminar/2005/seminar-details/20051118Taketa.pdf) and wanted to evaluate the formula on page 7 with D=X, i.e. not a constant.but simply the way to compute an expected value (of course with D as a constant as in this specific paper, it is much easier).

But i cannot get maple evaluate it numerically.

Maybe you have an idea?

thanks a lot...