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edgar

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19 years, 279 days
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original problem...

edgar 669
October 24 2006
That fix doesn't work on the following, which was the original problem. I simplified it for my first post.

> f := 1/(1-2^s);

Maple Equation

> p := 2*Pi/log(2);

Maple Equation

> series(f,s=I*p);

Maple Equation

> residue(f,s=I*p);

Maple Equation

> `normal/expanded`:=combine:

> residue(f,s=I*p);

Maple Equation

>

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OK...

edgar 669
October 23 2006
> phase(1/sin(x),x=-3..3); Error, (in sprintf) insufficient parameters for floating point format

(r^2)^(3/2)...

edgar 669
October 20 2006
The "simplification" (r^2)^(3/2) to r^3 is, in general, WRONG!!! For complex numbers r. Or even r=-1. That is why Maple does not do this simplification. If you want Maple to do this (and similar), you can write simplify( ... ,symbolic) --- G A Edgar

It depends ......

edgar 669
October 15 2006
It seems Georgios assumed you are using Windows. Are you? Init files may vary depending on the OS you use. On my Mac, I can have a file ~/.mapleinit and the commands there will be executed whenever Maple opens. --- G A Edgar

new maple primes?...

edgar 669
September 27 2006
Does the new, redesigned, maple primes have this useful feature? --- G A Edgar

Question 2...

edgar 669
September 23 2006
Now let's guess what question 2 means...

solve(y(x)+3*int((s+t)*y(t), t = 0 .. 1) = x^2+1, y)

How about: y is an unknown function, s is a given number, and this equation should hold for all values of x ?? In that case, try this:

> EQUATION := y(x)+3*int((s+t)*y(t), t = 0 .. 1) = x^2+1;

Maple Equation

The second term does not depend on x, we differentiate to get a differential equation...

> diff(%,x);

Maple Equation

> ysol := dsolve(%,y(x));

Maple Equation

Now put this solution back in, and solve for the constant:

> subs(y = (x -> x^2+C),EQUATION);

Maple Equation

> simplify(%);

Maple Equation

> solve(%,C);

Maple Equation

> subs(_C1=%,ysol);

Maple Equation

And that's our solution. Check:

> rhs(%); yy := unapply(%,x);

Maple Equation

Maple Equation

> subs(y=yy,EQUATION);

Maple Equation

> simplify(%);

Maple Equation

>

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unclear...

edgar 669
September 23 2006
What you want is unclear. Let's take the first one...

solve(y(x)+3*int((s+t)*y(t), t = 0 .. 1) = x^2+1, x)

What do you mean?
Perhaps: y(x) is a given function, s is a given number, and we want to solve for x ?? Like this:

> EQUATION := y(x)+3*int((s+t)*y(t), t = 0 .. 1) = x^2+1;

Maple Equation

> subs({y = sqrt,s=1},EQUATION);

Maple Equation

> simplify(%);

Maple Equation

> fsolve(%,x);

Maple Equation

>

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OK today...

edgar 669
September 23 2006
OK today --- G A Edgar

but......

edgar 669
September 21 2006
Having posted that, I see that it actually did know who I was. --- G A Edgar

10.05...

edgar 669
August 02 2006
Yesterday I downloaded and installed the latest upgrade to Maple 10.05 for OS X. Where did you download from? 10.04 is all I can find. --- G A Edgar

product...

edgar 669
June 30 2006
It seems to be something special about "product" ... and "sum" type(product(a,b),'product'(anything, anything)); false type(somethingelse(z,w),'somethingelse'(anything,anything)); true type(sum(a,b),'sum'(anything, anything)); false type('Product'(a,i=1..m),'Product'(anything, anything)); true --- G A Edgar

What else?...

edgar 669
May 05 2006
I get this even if I start dragging from the left margin, far to the left of the integral sign. So it's a bug in selection? Here is another example... I tried to select the whole thing, and I did get the "3 +" but still not the integral sign??

> 3+Int(4*x,x);

Maple Equation

> 3+4 x ⅆx6\"

Error, missing operator or `;`

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MatrixFunction...

edgar 669
March 31 2006

> with(LinearAlgebra):
A := Matrix([[-13, -10], [21, 16]]);

Maple Equation

> MatrixFunction(A, sin(x), x);

Maple Equation

>

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complex number...

edgar 669
March 22 2006
'I' is maple's symbol for complex number sqrt(-1). Your formula involves complex numbers. --- G A Edgar

workaround...

edgar 669
March 22 2006
The -> notation does not evaluate the formula, so it just has 'N' in it, not 2. The workaround causes the evaluation. BUT that still leaves the question of why these two are different:

> restart;sum(a[n](t)*b(n),n=1..N);diff(%,t);

Maple Equation

Maple Equation

> restart;sum(a[n](t)*exp(n),n=1..N);diff(%,t);

Maple Equation

Maple Equation

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