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From: us on 5 Aug 2010 05:08
"Rogelio" <rogelio.a.mancisidor(a)student.bi.no> wrote in message <i3dtko$nh$1(a)fred.mathworks.com>...
> "Paul " <unicybsatr(a)gmail.com> wrote in message <i3dnp8$5gg$1(a)fred.mathworks.com>...
> > Walter Roberson <roberson(a)hushmail.com> wrote in message <wSo6o.57866$YX3.28517(a)newsfe18.iad>...
> > > Paul wrote:
> > >
> > > > I want to find value of integral from 0 to 1 exp(t*sin(x))*dx
> > > > with function int I can find integral from 0 to 1 exp(sin(x))*dx
> > > > But if I add independent variable t, than I receive an error from
> > > > function int()
> > > >
> > > > How can I evaluate that integral?
> > >
> > > My speculation would be that you are not telling int() which variable to
> > > integrate over.
> > >
> > > Show us how you are calling int() and any critical code leading up to that.
> > syms x t;
> > int(exp(-t*sin(x)),x,0,1)
>
> Hi Paul,
> As I understand what you want is a numerical integration.

not according to the OP's example...

us
From: Paul on 5 Aug 2010 06:14
"us " <us(a)neurol.unizh.ch> wrote in message <i3dv25$t7h$1(a)fred.mathworks.com>...
> "Rogelio" <rogelio.a.mancisidor(a)student.bi.no> wrote in message <i3dtko$nh$1(a)fred.mathworks.com>...
> > "Paul " <unicybsatr(a)gmail.com> wrote in message <i3dnp8$5gg$1(a)fred.mathworks.com>...
> > > Walter Roberson <roberson(a)hushmail.com> wrote in message <wSo6o.57866$YX3.28517(a)newsfe18.iad>...
> > > > Paul wrote:
> > > >
> > > > > I want to find value of integral from 0 to 1 exp(t*sin(x))*dx
> > > > > with function int I can find integral from 0 to 1 exp(sin(x))*dx
> > > > > But if I add independent variable t, than I receive an error from
> > > > > function int()
> > > > >
> > > > > How can I evaluate that integral?
> > > >
> > > > My speculation would be that you are not telling int() which variable to
> > > > integrate over.
> > > >
> > > > Show us how you are calling int() and any critical code leading up to that.
> > > syms x t;
> > > int(exp(-t*sin(x)),x,0,1)
> >
> > Hi Paul,
> > As I understand what you want is a numerical integration.
>
> not according to the OP's example...
>
> us

yes, I want numerical integration, of function with independent variable t.
But function is not explicitly integrated.
From: us on 5 Aug 2010 07:43
"Paul " <unicybsatr(a)gmail.com> wrote in message <i3e2td$tp$1(a)fred.mathworks.com>...
> "us " <us(a)neurol.unizh.ch> wrote in message <i3dv25$t7h$1(a)fred.mathworks.com>...
> > "Rogelio" <rogelio.a.mancisidor(a)student.bi.no> wrote in message <i3dtko$nh$1(a)fred.mathworks.com>...
> > > "Paul " <unicybsatr(a)gmail.com> wrote in message <i3dnp8$5gg$1(a)fred.mathworks.com>...
> > > > Walter Roberson <roberson(a)hushmail.com> wrote in message <wSo6o.57866$YX3.28517(a)newsfe18.iad>...
> > > > > Paul wrote:
> > > > >
> > > > > > I want to find value of integral from 0 to 1 exp(t*sin(x))*dx
> > > > > > with function int I can find integral from 0 to 1 exp(sin(x))*dx
> > > > > > But if I add independent variable t, than I receive an error from
> > > > > > function int()
> > > > > >
> > > > > > How can I evaluate that integral?
> > > > >
> > > > > My speculation would be that you are not telling int() which variable to
> > > > > integrate over.
> > > > >
> > > > > Show us how you are calling int() and any critical code leading up to that.
> > > > syms x t;
> > > > int(exp(-t*sin(x)),x,0,1)
> > >
> > > Hi Paul,
> > > As I understand what you want is a numerical integration.
> >
> > not according to the OP's example...
> >
> > us
>
> yes, I want numerical integration, of function with independent variable t.
> But function is not explicitly integrated.

well... then WHY do you use symbolic notation(?)...
this just does not make sense...
THINK - then POST...

us
From: Paul on 5 Aug 2010 11:42
"us " <us(a)neurol.unizh.ch> wrote in message <i3e849$3t$1(a)fred.mathworks.com>...
> "Paul " <unicybsatr(a)gmail.com> wrote in message <i3e2td$tp$1(a)fred.mathworks.com>...
> > "us " <us(a)neurol.unizh.ch> wrote in message <i3dv25$t7h$1(a)fred.mathworks.com>...
> > > "Rogelio" <rogelio.a.mancisidor(a)student.bi.no> wrote in message <i3dtko$nh$1(a)fred.mathworks.com>...
> > > > "Paul " <unicybsatr(a)gmail.com> wrote in message <i3dnp8$5gg$1(a)fred.mathworks.com>...
> > > > > Walter Roberson <roberson(a)hushmail.com> wrote in message <wSo6o.57866$YX3.28517(a)newsfe18.iad>...
> > > > > > Paul wrote:
> > > > > >
> > > > > > > I want to find value of integral from 0 to 1 exp(t*sin(x))*dx
> > > > > > > with function int I can find integral from 0 to 1 exp(sin(x))*dx
> > > > > > > But if I add independent variable t, than I receive an error from
> > > > > > > function int()
> > > > > > >
> > > > > > > How can I evaluate that integral?
> > > > > >
> > > > > > My speculation would be that you are not telling int() which variable to
> > > > > > integrate over.
> > > > > >
> > > > > > Show us how you are calling int() and any critical code leading up to that.
> > > > > syms x t;
> > > > > int(exp(-t*sin(x)),x,0,1)
> > > >
> > > > Hi Paul,
> > > > As I understand what you want is a numerical integration.
> > >
> > > not according to the OP's example...
> > >
> > > us
> >
> > yes, I want numerical integration, of function with independent variable t.
> > But function is not explicitly integrated.
>
> well... then WHY do you use symbolic notation(?)...
> this just does not make sense...
> THINK - then POST...
>
> us

because quadl can't evaluate integral with parameter.
From: Walter Roberson on 5 Aug 2010 12:09
Paul wrote:
> "us " <us(a)neurol.unizh.ch> wrote in message
> <i3dv25$t7h$1(a)fred.mathworks.com>...
>> "Rogelio" <rogelio.a.mancisidor(a)student.bi.no> wrote in message
>> <i3dtko$nh$1(a)fred.mathworks.com>...
>> > "Paul " <unicybsatr(a)gmail.com> wrote in message
>> <i3dnp8$5gg$1(a)fred.mathworks.com>...
>> > > Walter Roberson <roberson(a)hushmail.com> wrote in message
>> <wSo6o.57866$YX3.28517(a)newsfe18.iad>...
>> > > > Paul wrote:
>> > > > > > > > I want to find value of integral from 0 to 1
>> exp(t*sin(x))*dx
>> > > > > with function int I can find integral from 0 to 1 exp(sin(x))*dx
>> > > > > But if I add independent variable t, than I receive an error
>> from > > > > function int()
>> > > > > > > > > How can I evaluate that integral?
>> > > > > > > My speculation would be that you are not telling int()
>> which variable to > > > integrate over.
>> > > > > > > Show us how you are calling int() and any critical code
>> leading up to that.
>> > > syms x t;
>> > > int(exp(-t*sin(x)),x,0,1)
>> > > Hi Paul,
>> > As I understand what you want is a numerical integration.
>>
>> not according to the OP's example...
>>
>> us
>
> yes, I want numerical integration, of function with independent variable t.
> But function is not explicitly integrated.

I tried a number of standard conversions and the function simply does
not have an explicit form with any of them.

The one exception is that it can be explicitly represented as an
infinite sum. I would have to do further analysis to be sure, but it
appears that possibly that infinite sum would be divergent for abs(t) >
1, especially for t < -1
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