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21did21
Dec 31, 2011, 8:06:09 AM12/31/11
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hello world !
context:
I have about 1e22 samples that have an average size of third-9. I could content myself with this information to characterize this population but it is not enough. Indeed, the size of third-9 is a medium in reality there are samples that have a size of eight fourth-and other first-12.
solution:
I know that the size distribution of my sample follows a log normal reversed. So I can, knowing the average value, the number of sample mean and standard deviation in software such as MATLAB to generate me a size distribution that meets these criteria.
problem:
I can not understand how I can do this with software.
- I decided to MATLAB because it is a very powerful software that is able to do this in one line.
The trouble is that I expected to do this:
[size, number] = logninv (1e22, 3rd-9, 0.05)
and have direct variables in size and number distribution desired. and drawing number according to size to get my distribution like a histogram :
http://www.google.fr/imgres?q=histogram&um=1&hl=fr&sa=N&biw=1600&bih=735&tbm=isch&tbnid=DQVF5Oamf1nQHM:&imgrefurl=http://www.vistadatavision.com/reports/histogram/&docid=4932O0wS-rWiQM&imgurl=http://www.vistadatavision.com/uploads/images/reports/histogram_rh_48.png&w=650&h=457&ei=fAj_TqWVBcOdOpvG6JgB&zoom=1&iact=hc&vpx=478&vpy=286&dur=1179&hovh=188&hovw=268&tx=190&ty=121&sig=104039641612689214034&page=1&tbnh=121&tbnw=172&start=0&ndsp=33&ved=1t:429,r:10,s:0
context:
I have about 1e22 samples that have an average size of third-9. I could content myself with this information to characterize this population but it is not enough. Indeed, the size of third-9 is a medium in reality there are samples that have a size of eight fourth-and other first-12.
solution:
I know that the size distribution of my sample follows a log normal reversed. So I can, knowing the average value, the number of sample mean and standard deviation in software such as MATLAB to generate me a size distribution that meets these criteria.
problem:
I can not understand how I can do this with software.
- I decided to MATLAB because it is a very powerful software that is able to do this in one line.
The trouble is that I expected to do this:
[size, number] = logninv (1e22, 3rd-9, 0.05)
and have direct variables in size and number distribution desired. and drawing number according to size to get my distribution like a histogram :
http://www.google.fr/imgres?q=histogram&um=1&hl=fr&sa=N&biw=1600&bih=735&tbm=isch&tbnid=DQVF5Oamf1nQHM:&imgrefurl=http://www.vistadatavision.com/reports/histogram/&docid=4932O0wS-rWiQM&imgurl=http://www.vistadatavision.com/uploads/images/reports/histogram_rh_48.png&w=650&h=457&ei=fAj_TqWVBcOdOpvG6JgB&zoom=1&iact=hc&vpx=478&vpy=286&dur=1179&hovh=188&hovw=268&tx=190&ty=121&sig=104039641612689214034&page=1&tbnh=121&tbnw=172&start=0&ndsp=33&ved=1t:429,r:10,s:0
21did21
Dec 31, 2011, 8:07:08 AM12/31/11
to
John D'Errico
Dec 31, 2011, 9:05:08 AM12/31/11
to
"21did21 " <21d...@gmx.com> wrote in message <jdn1ds$8ip$1...@newscl01ah.mathworks.com>...
so more data than you can store on any reasonable computer.
Did you measure this data?
Lets see, on a exaflop machine (roughly the fastest computer
that we have built to date) so dealing with 1e15 samples
per second, this will still take 1e7 seconds to process. So
just to compute the mean of your data, it will take at least
4 months to process, and that on a computer that is MANY
orders of magnitude bigger than anything a normal person
has ever used.
What does "average size third-9" mean?
"is a medium in reality"? I thought that a medium is someone
with a crystal ball?
eight-fourth?
first-12?
> solution:
> I know that the size distribution of my sample follows a log normal reversed. So I can, knowing the average value, the number of sample mean and standard deviation in software such as MATLAB to generate me a size distribution that meets these criteria.
>
> problem:
> I can not understand how I can do this with software.
> - I decided to MATLAB because it is a very powerful software that is able to do this in one line.
>
It cannot read your mind, and my abilities as a medium
are far from good.
> The trouble is that I expected to do this:
> [size, number] = logninv (1e22, 3rd-9, 0.05)
MATLAB cannot comprehend what "3rd-9" means. This
is not a legal variable, nor a legal numeric format. And I'm
not sure what you expect logninv to return, but you might
want to read the help for logninv.
Naming a variable with the name size is a terrible thing to
do, since it overloads the size function, an incredibly useful
tool in matlab. Your next question on the group will be an
equally unintelligible request as to why size no longer works
for you.
I'm completely perplexed. This is not April 1st either.
John
> hello world !
>
> context:
> I have about 1e22 samples that have an average size of third-9. I could content myself with this information to characterize this population but it is not enough. Indeed, the size of third-9 is a medium in reality there are samples that have a size of eight fourth-and other first-12.
>
Do I believe this? You have nearly Avogadro's number of samples,
>
> context:
> I have about 1e22 samples that have an average size of third-9. I could content myself with this information to characterize this population but it is not enough. Indeed, the size of third-9 is a medium in reality there are samples that have a size of eight fourth-and other first-12.
>
so more data than you can store on any reasonable computer.
Did you measure this data?
Lets see, on a exaflop machine (roughly the fastest computer
that we have built to date) so dealing with 1e15 samples
per second, this will still take 1e7 seconds to process. So
just to compute the mean of your data, it will take at least
4 months to process, and that on a computer that is MANY
orders of magnitude bigger than anything a normal person
has ever used.
What does "average size third-9" mean?
"is a medium in reality"? I thought that a medium is someone
with a crystal ball?
eight-fourth?
first-12?
> solution:
> I know that the size distribution of my sample follows a log normal reversed. So I can, knowing the average value, the number of sample mean and standard deviation in software such as MATLAB to generate me a size distribution that meets these criteria.
>
> problem:
> I can not understand how I can do this with software.
> - I decided to MATLAB because it is a very powerful software that is able to do this in one line.
>
are far from good.
> The trouble is that I expected to do this:
> [size, number] = logninv (1e22, 3rd-9, 0.05)
is not a legal variable, nor a legal numeric format. And I'm
not sure what you expect logninv to return, but you might
want to read the help for logninv.
Naming a variable with the name size is a terrible thing to
do, since it overloads the size function, an incredibly useful
tool in matlab. Your next question on the group will be an
equally unintelligible request as to why size no longer works
for you.
I'm completely perplexed. This is not April 1st either.
John
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