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Re: Can it be done - easily?

Barry Culhane wrote in message <6od25q$hn9 at>...
>Myself and two workmates are software developers.  One guy wanted a
>formula to calculate a result for the following equation...
>     Z = sum of X/Y where X is a fixed number, and Y ranges from A-B in
>fixed steps...
>     i.e... X=10000 ; Y=100,200,300...1000
>     i.e... Z= 10000/100 + 10000/200 + ... 10000/1000 =  292.896
> ...

Hi Barry,
it can be done - easily.
if you have a stepsize, a starting value, end value (all three defining 
y), and a factor x, you can instruct Mathematica to calculate

f[x_,start_,end_,step_] := NSum[x/y,{y,start,end,step}]];

You can investigate the time consumed by this by, e.g. :

Timing[  f[1,1,10^6,1]  ]

{0.05 Second, 14.3927}

So: easy and fast...


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