bessel functions

[John_8490-disab]

Hi, I am trying to use bessel functions ber and bei and keep getting an error "Found a number greaterthan 10^307".

I do not think the answer will go beyond 10^307.

Simple way to see the issue is
Evaluate ber(0,78)=

Is this a known issue with M14? - John

[ptc-1368288]

On 1/18/2010 3:43:41 PM, John_8490 wrote:
>Hi, I am trying to use bessel
>functions ber and bei and keep
>getting an error "Found a
>number greaterthan 10^307".
>
>I do not think the answer will
>go beyond 10^307.
>
>Simple way to see the issue is
>Evaluate ber(0,78)=
>
>Is this a known issue with
>M14? - John
____________________________

As long as it plots, you may be able to cay in formulas ! For the numerical local evaluation, check for any recurrence.

jmG

[ptc-1368288]

On 1/18/2010 4:55:21 PM, jmG wrote:
>On 1/18/2010 3:43:41 PM, John_8490
>wrote:
>>Hi, I am trying to use bessel
>>functions ber and bei and keep
>>getting an error "Found a
>>number greaterthan 10^307".
>>
>>I do not think the answer will
>>go beyond 10^307.
>>
>>Simple way to see the issue is
>>Evaluate ber(0,78)=
>>
>>Is this a known issue with
>>M14? - John
>____________________________
>
>As long as it plots, you may be able to
>cay in formulas !
For the numerical local evaluation, check for any
>recurrence.
>ber(0,77) calculates ... plots up to 43

Attached: roots up to the max built-in capability 43


>jmG

[StuartBruff]

On 1/18/2010 3:43:41 PM, John_8490 wrote:
== Hi, I am trying to use bessel functions ber and bei and keep getting an error "Found a number greaterthan 10^307".
== I do not think the answer will go beyond 10^307.

I think it should be about -8.757*10^21

== Simple way to see the issue is Evaluate ber(0,78)=

OK

Try replacing it with:

Ber(n,x):=Re(Jn(n,x*exp(3πi/4)))

== Is this a known issue with M14?

Don't know, but it's an issue with M11 as well.

Stuart

[John_8490-disab]

Thanks Stuart.
That works...
I just found the same here
http://www.2dcurves.com/gamma/gammabs.html
-John

[ptc-1368288]

On 1/18/2010 5:12:55 PM, John_8490 wrote:
>Thanks Stuart.
>That works...
>I just found the same here
>http://www.2dcurves.com/gamma/
>gammabs.html
>-John
_______________________

My calculations give

ber(0,78) = -1.614E+22

jmG

[ptc-1368288]

On 1/18/2010 7:18:23 PM, jmG wrote:
>On 1/18/2010 5:12:55 PM, John_8490
>wrote:
>>Thanks Stuart.
>>That works...
>>I just found the same here
>>http://www.2dcurves.com/gamma/
>>gammabs.html
>>-John
>_______________________
>
>My calculations give
>
>ber(0,78) = -1.614E+22
>
>jmG
________________________

As declared, however no true value can exist.



jmG

[StuartBruff]

On 1/18/2010 7:57:57 PM, jmG wrote:
On 1/18/2010 7:18:23 PM, jmG wrote:
>On 1/18/2010 5:12:55 PM, John_8490
>wrote:
>>Thanks Stuart.
>>That works...
>>I just found the same here
>>http://www.2dcurves.com/gamma/
>>gammabs.html
>>-John
>_______________________
>
>My calculations give
>
>ber(0,78) = -1.614E+22
>
>jmG
________________________

As declared, however no true value can exist.

Possibly it can.

Stuart