Could you let us know, which interpretation was it? Markov chains and transition matrices, or just plain old linear algebra and diagonalization?

Inquiring minds would love to find out.

acer

Could you let us know, which interpretation was it? Markov chains and transition matrices, or just plain old linear algebra and diagonalization?

Inquiring minds would love to find out.

acer

`testfloat` or verify,float might be better still than is@fnormal.

acer

`testfloat` or verify,float might be better still than is@fnormal.

acer

Hi Axel, How about this,

fname := "D:\\temp\\minttemp.txt";

ps. Axel, I still "owe" you a promised post on the Compiler and C function-pointer stuff.

acer

A useful suggestion, djc.

I wonder why `expand/Sum` and `student/expand/Sum` differ in this way. (Are students less likely to handle infinite bounds?!)

interface(verboseproc=3):
eval(`expand/Sum`);
eval(`student/expand/Sum`);

acer

A useful suggestion, djc.

I wonder why `expand/Sum` and `student/expand/Sum` differ in this way. (Are students less likely to handle infinite bounds?!)

interface(verboseproc=3):
eval(`expand/Sum`);
eval(`student/expand/Sum`);

acer

Yes, I already pointed out that the wording of the error message was not good.

I mentioned that I didn't have Maple in front of me at the time, to check which symbolic quantity would act differently. As usual when I go by memory, I get the idea right but the detail wrong.

> Pi(17);
                                    Pi(17)
 
> Pi(17.0);
                                   Pi(17.0)
 
> evalf(Pi(17));
                                    Pi(17)
 
> evalf(Pi(17.0));
                                   Pi(17.0)

There are lots of expressions in Maple which evaluate to numeric under evalf, but which would not do so if first applied to an argument (as if they were operators).

Brushing off the expression/operator distinctions, even if only for (complex) numeric values, if a bad habit, and is asking for future trouble.

acer

Yes, I already pointed out that the wording of the error message was not good.

I mentioned that I didn't have Maple in front of me at the time, to check which symbolic quantity would act differently. As usual when I go by memory, I get the idea right but the detail wrong.

> Pi(17);
                                    Pi(17)
 
> Pi(17.0);
                                   Pi(17.0)
 
> evalf(Pi(17));
                                    Pi(17)
 
> evalf(Pi(17.0));
                                   Pi(17.0)

There are lots of expressions in Maple which evaluate to numeric under evalf, but which would not do so if first applied to an argument (as if they were operators).

Brushing off the expression/operator distinctions, even if only for (complex) numeric values, if a bad habit, and is asking for future trouble.

acer

If I recall, that error can occur when expressions and procedures are mixed. It's not a very clear wording. I don't have Maple right now, but you might try,

fsolve( tt->zerovalue(tt)-8, 195..200);

fsolve( 'zerovalue'(tt)-8, tt=195..200);

While Maple can treat 8 as an operator -- 8(17) gives 8, etc -- it's not true of general symbolic or exact radical numeric quantities. So it seems more consistent to disallow 8 to be used alongside zerovalue, than to have a more confusing behavioural discrepency between 8 and sqrt(2) say.If I recall, not everyone agrees on this.

acer

If I recall, that error can occur when expressions and procedures are mixed. It's not a very clear wording. I don't have Maple right now, but you might try,

fsolve( tt->zerovalue(tt)-8, 195..200);

fsolve( 'zerovalue'(tt)-8, tt=195..200);

While Maple can treat 8 as an operator -- 8(17) gives 8, etc -- it's not true of general symbolic or exact radical numeric quantities. So it seems more consistent to disallow 8 to be used alongside zerovalue, than to have a more confusing behavioural discrepency between 8 and sqrt(2) say.If I recall, not everyone agrees on this.

acer

You could try something like this,

Explore(DEtools[DEplot]({diff(x(t),t) = v(t), diff(v(t),t) = c*v(t)+k*sin(x(t))},
                        [x(t),v(t)],t=0..20,
                        [[x(0)=A,v(0)=B],[x(0)=A+Pi,v(0)=B],
                         [x(0)=A,v(0)=-B],[x(0)=A+Pi,v(0)=-B]],
                        arrows=none));

When the dialogue box pops up, set the ranges something like this (adjust if you wish),

  A:      0.0     5.0
  B:     -5.0     0.0
  c:     -1.0    -0.1
  k:     -1.0    -0.1
  t:   skip
  arrows:  skip
  none:  skip

Make sure that it runs in a "New" kernel connection.

acer

You could try something like this,

Explore(DEtools[DEplot]({diff(x(t),t) = v(t), diff(v(t),t) = c*v(t)+k*sin(x(t))},
                        [x(t),v(t)],t=0..20,
                        [[x(0)=A,v(0)=B],[x(0)=A+Pi,v(0)=B],
                         [x(0)=A,v(0)=-B],[x(0)=A+Pi,v(0)=-B]],
                        arrows=none));

When the dialogue box pops up, set the ranges something like this (adjust if you wish),

  A:      0.0     5.0
  B:     -5.0     0.0
  c:     -1.0    -0.1
  k:     -1.0    -0.1
  t:   skip
  arrows:  skip
  none:  skip

Make sure that it runs in a "New" kernel connection.

acer

You originally had two different problems. The second problem, that `i1` returns a nonreal value for some omega in the range, is still present. See bits about Re() and Im() above. Try calling `i1`, as you have it now, for some values, to see what it returns.

acer

You originally had two different problems. The second problem, that `i1` returns a nonreal value for some omega in the range, is still present. See bits about Re() and Im() above. Try calling `i1`, as you have it now, for some values, to see what it returns.

acer