Why do adjacent bins differ so widely in histograms?

Looking at the tutorial "Histogram Measurements with NI High-Speed Digitizers", we see that neighboring histogram levels differ by a factor of 3 or more, even though the overall curve is as expected.
I have the same problem in my application in the UNCC Adaptive Optics Lab. Why does this occur?

Short answer - you are probably seeing small number statistics in action. Long answer - most histograms are generated to find the mean and standard deviation of a random process. If the number of points in any particular bin is random, the one sigma variation of the number of hits in each bin is the square root of the number of hits in that bin. So, if you want a smooth curve, you need lots of hits. For example, assume you have a histogram that has a width at the 1/e point of four bins. The peak is 10 hits high. The next bin is 3 hits. The next over from that 4. This represents a Gaussian with a true peak height of 7.3 and a 1 sigma variation in the hits for each bin. There is about a 5% chance of this occurring. Take the same underlying random phenomenon a
nd take a histogram with a true height of 7300 hits and then apply the same one sigma variation to each bin. You get a sequence of 7385, 5610, and 2737 - much smoother.
You need to do this sort of calculation for any histogram you generate. Then you need to determine if the results are interesting physics or just random chance. Nobel prizes have hinged on this very question.
You need to determine whether or not you expect a Gaussian curve. If you are taking the voltage histogram of the tops of two square waves, you should get two sharp spikes. Depending upon the width of your bins, you may or may not get tails on the spikes. If you are capturing the whole pulse, you would not expect a Gaussian peak shape due to ringing at the edges of the pulse.
So, remember what you are measuring, analyze the statistics, and look for the underlying phenomenon. Good luck! Have fun!
This account is no longer active. Contact ShadesOfGray for current posts and information.

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/usr/bin/diff problem

Hi,
we just migrated one of our apps from Solaris 8 to Solaris 10.
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As per normal RCS procedure, before the new file is checked in, it's being compared to the old version using /usr/bin/diff.
On the old Server (Netra T4, Solaris 8) the diff was running for about 15 Minutes.
On the new Server (V245, Solaris 10) the diff now takes 2 1/2 hours !!
I haven't found an obvious cause for this, so I was thinking about using dtrace to find out why the diff on the new server is taking that long.
On the other side, I don't have much experience with dtrace yet....
I would very much appreciate any help you could offer to help me find the problem.
thanks
--Marc

In the future, you might consider asking Unix and Terminal oriented questions in the Mac OS X Technologies > Unix Forum
<http://discussions.apple.com/forum.jspa?forumID=735>

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Thanks, Barbara! That did the trick. I was in expert mode but I clicked on 'guided' then clicked on 'expert' again and it showed up.

Juuuust in case you are wondering why your bass bin doesn't work in

you need to go to the THX SETUP CONSOLE and "Enable Bass Redirection"
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[img"]http://img54.imageshack.us/img54/999/bassyc5yk7.gif">

Hi,
Whenever you have a question, it helps to post:
(1) The version of Oracle (and any other relevant software) you're using
(2) A little sample data (just enough to show what the problem is) from all the relevant tables
(3) The results you want from that data (If you're asking about a DML statement, such as UPDATE, this will be the state of the tables when everything is finished.)
(4) Your best attempt so far (formatted) (You posted this, but since it's unformated, it's very hard to read.)
(5) The full error message (if any), including line number.
Executable SQL statements (like "CREATE TABLE AS ..." or "INSERT ..." statements) are best for (2).
If you can present your problem using commonly available tables (for example, tables in the scott schema, or views in the data dictionary), then you can omit (2).
Formatted tabular output is okay for (3).
I'll bet you know something more specific about the problem than "it doesn't work", such as an error message or wrong results. Why not share that information?
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Why is cgi-bin special?

I have a server side perl script running in the cgi-bin
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Once the html is returned to the client, how can the
rendering be different from a static html page? I'm saying that if
you do "view source", once from the returned html
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The only difference is the URL of the page. When
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Thanks, Barbara! That did the trick. I was in expert mode but I clicked on 'guided' then clicked on 'expert' again and it showed up.

Why Does Paragraph Numbering Differ Between WYSIWYG and WebHelp?

Howdy. I've returned to a relatively simple and small (300+ topic) project using RH7 7.03.001on my XP Professional Version 2002 SP3 PC. What's required and what shows in the Word source docs and RH7 (editor and preview modes) after import is, for example:
Steps To Accomplish
1.      Log on to the system.
2.      Select Administration view.
NOTE
Check for user already existing prior to creating a new account.
3.      <Click> the Add User button.
4.      …
But what WebHelp shows in the end user's IE6 SP2 browser is:
Steps To Accomplish
1.      Log on to the system.
2.      Select Administration view.
NOTE
Check for user already existing prior to creating a new account.
4.      <Click> the Add User button.
5.      …
My observation is that RH7 inserts an <li style="list-style: none"> and </li> pair around every NOTE paragraph group in the generated file, which increments the step number objectionably. (Though a "small" project, I am not going to hand-delete these though that solves the problem...)
Hmm, do I need two step numbering styles -- one that starts at 1 (pre-NOTE) and one that does not restart (post-NOTE)? The Bullets and Numbering dialogue doesn't offer either option, at least via RH7's Format / Styles route. And would that help anyway on the second and subsequent Note groups that might occur? Just tried it -- no difference. Auggh. I've wrestled with styles and formats a bit but obviously don't understand -- or is this an RH7 bug or feature? (I would expect WYSIWYG to be just that...)
I have attached a PDF describing my problem in more detail, though I realize this is not the preferred method...
Thanks all!
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Thank you, Willam, for your prompt, thoughtful and complimentary reply. I'm somewhat relieved that I haven't missed something obvious but concerned that more effort will have to be applied.
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Meanwhile, my comment and question:
1.      If WYSIWYG is to be trusted for a commercially mature product, then if not true I'd consider the product to have a bug (notwithstanding someone coming forth with a fix that doesn’t require postprocessing!).
2.      Does RH8 exhibit this same paragraph-numbering discrepancy? (My customer plans to purchase RH so "their people" can also work the project. This could become problematic, and not just because once converted, as another post points out, the RH8 project cannot be used by RH7. Whee!)
Thanks, all, for reading. Please keep adding to the body of knowledge!
Steve

Why Creation Bin Structure is not in full following seting up?

I created bin structure at spro as 03-01-01 to 03-10-10 increment 03-01-01 but when I check bin at t-code LX03 which the system shows only 03-01-01 to 03-02-10 (20 bins) so I could not understand this why system shows bin no in full following me seting up. _How to do, check and change this?_ Moreover I could not also find the missing bin in the system.

Template: CCCNNCNNCC
Give template as : - - - AA- BB--
Read "-" as a blank space.

Stats differ for vda "pool-show" vs. "pool-desktops"

Hi,
has anyone seen this before? Sun VDI 3.1 connected to a vCenter infrastructure. vda pool-show shows a different number of desktops (145) compared to vda pool-desktops (101)? Judging from the VMs in vCenter vda pool-show seems to be correct, but why would pool-desktops differ?
# vda pool-show POOL
Assignment Status: Enabled
Desktop Assignments: personal
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            Cloning: Enabled
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Assigned Desktops: 136
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Opened a support case, turned out to be a known limitation for the command line tools. 'vda pool-desktops' limits it output to 101 items for performance reasons (but unfortunately doesn't say so). A workaround is to gather the data directly from the database. In our case we needed to obtain the desktop -> user assignments for a specific pool, which we did with the follwing bash/SQL snippet.
#!/bin/bash
[ $# -eq 1 ] || { echo 'Pool name required'; exit 1; }
POOL=$1
/opt/SUNWvda/mysql/bin/mysql --defaults-file=/etc/opt/SUNWvda/my.cnf -N -p vda <<EOM
select d.name, d.state, u.distinguished_name
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order by d.name;
select d.name, d.state
from t_desktop as d, t_pool as p
where p.name = "$POOL" and p.id = d.pool_id and d.state='available'
order by name;
EOMThe second SQL query (for the available desktops) might be merged into the first one, I am not much of a SQL guy though.

Web galleries put images under a bin directory

The web galleries put the images (both thumb and large) in a path like content/bin/images/... For hosts that use Microsoft Internet Information Server, the bin part of this path breaks the link to images, so they don't display. WHY IN G's NAME do you use bin? bin is for executables, in both unix and Windows, surely.
Because I use a host that uses IIS, I can't use Lightroom-generated web galleries.

Open the folder default_html.lrwengine (it's inside the lightroom app folder) (you should make a backup copy just in case)
Open the file galleryInfo.lrweb
after the line ["photoSizes.thumb.width"] = 130,
Add
["photoSizes.large.directory"] = "large",
["photoSizes.thumb.directory"] = "thumb",
In grid.html change the line <img src="$others/bin/images/thumb/<%= image.exportFilename %>.jpg" id="ID<%= image.imageID %>_thumb" alt="" class="thumb" />
to <img src="$others/thumb/<%= image.exportFilename %>.jpg" id="ID<%= image.imageID %>_thumb" alt="" class="thumb" />
and in detail.html change <img src="bin/images/large/<%= image.exportFilename %>.jpg"
to
<img src="large/<%= image.exportFilename %>.jpg"
That should get you going.
As to why it uses bin? no idea..

Why is the INVOICE date different than the ORDER date?

Something odd is happening... I'm receiving workflow notifications from Business Catalyst for Invoices, but sometimes the date of the order is the day before I receive the invoice. This is causing havoc on the shipping side because when I print out the invoice packing slips and export the order files, they don't match up and sometimes customers get missed.
Any idea why the invoice date would be different than the order date and how do I fix it to make them the same?
Thanks in advance!

Hey there,
An invoice is not an order. That is an important thing to know.
An order is generated through a few means but mainly as soon as one product is added to a cart - that order exists and the date marked. An invoice is a purchase and comes from an order.
Create an order in the admin yourself and save it but add no invoice number. You can see you just made an order and you will see the button to generate invoice.
API can make an order and no invoice, a person can add items to cart and finish it the next day if they have their session open that long... Lots of reasons why these dates may differ.

Amount diff between Leading leder & non leading ledger (Parallel ledger)

Hi SAP Guru's
Write now we are working on ECC 6.0 with new gl. We have configure parallel ledger accounting & document splitting also.
But when I am seeing balances in 0L & 1L (GL Bal), system showing differences.When i am found out this difference it comes in Zero balance account(for document splitting).
my question is why the system showing diff balances in 0l & 1l?
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Can any plz help me out for above issues......
regards
Amar

No sir,
I have taken same fiscal yr variant.
My issue is solved............

DELETE ADJACENT DUPLCATES

Hi Experts,
I wonder why delete adjacent duplicate sometimes
doesn't work and sometimes doesn't. Any idea?
Thanks in advance.
Regards,
Rose

hi
chk this
DELETE ADJACENT DUPLICATES FROM itab.
Extras:
1. ... COMPARING f1 f2 ...
2. ... COMPARING ALL FIELDS
Effect
Deletes adjacent duplicate entries from the internal table itab. If there are n duplicate entries in succession, the first entry is retained, and the following n-1 entries are deleted.
Two lines are regarded as duplicates if their keys are identical.
The Return Code is set as follows:
SY-SUBRC = 0:
At least one duplicate was found, and at least one entry was deleted.
SY-SUBRC = 4:
No duplicates found, no entries deleted.
Addition 1
... COMPARING f1 f2 ...
Effect
Two lines of the internal table itab are regarded as duplicates if they have identical contents in the fields f1, f2, ...
Addition 2
... COMPARING ALL FIELDS
Effect
Two lines of the internal table are regarded as duplicates if all of their field contents are identical.
<b>Notes
The DELETE ADJACENT DUPLICATES statement works particularly well if you have sorted the internal table itab according to the fields that you want to compare when looking for duplicates. In this case, deleting adjacent duplicates is the same as deleting all duplicates. The direction of the sort is irrelevant.
If you do not know a comparison expression until runtime, you can specify it dynamically as the contents of the field name in the expression COMPARING ... (name) .... If name is empty at runtime, the comparison expression is ignored. If name contains an invalid component name, a runtime error occurs.
You can further restrict comparison expressions - both static and dynamic - by specifying offset and length.
Note
Performance:
When you delete a line of an internal table, index maintenance costs are incurred. These depend on the index of the table. The runtime is independent of the width of the table line.
Deleting a line from the middle of an internal table with 200 entries usually requires around 10 msn (standardized microseconds).
When you delete a set of entries using "DELETE itab FROM idx1 TO idx2." or "DELETE itab WHERE ...", index maintenance costs are only incurred once. This means that it is considerably more efficient than deleting entries in a LOOP.
If you want to delete adjacent duplicate entries from an internal table, use the variant " DELETE ADJACENT DUPLICATES FROM itab." instead of a LOOP construction.</b>

Recycle bin and 'clear disk space'

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also, if you search for the reyclebin it'll always return nothing, the only access to it is via the desktop folder assuming you actually have one, 'This PC' (aka 'my computer' or 'computer') are still accessible via search so why not the bin?
both of these I find pretty stupid to the point I call them bugs, there been anything about this...?

Hi,
The storage occupied in recyle bin under PC settings is the same as the storage occurpied in the bin in desktop, that means if you empty the recyle bin in desktop, then the recycle bin at the bottom of PC settings will also display empty.
And regarding to this sentence
"if you search for the reyclebin it'll always return nothing, the only access to it is via the desktop folder assuming you actually have one, 'This PC' (aka 'my computer' or 'computer') are still accessible via search so why not the bin?"
I don't quite understand this sentence, but search result should be related with "Indexng Options" under Control Panel\All Control Panel Items\Indexing Options
Yolanda Zhu
TechNet Community Support
'same as the one on the desktop' well no, its not;
why would you think I'd say otherwise?
also, considering the indexing should already contain the desktop, that doesn't make sense either, and I definitely haven't turned off indexing anywhere.

Executing /usr/bin/mail From Within Daemon

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Python:
cmd = "/bin/echo \"%s\" | /usr/bin/mail -s \"%s\" %s" % (messageText.strip(),subject,receiver)
os.system(cmd)
The question is, why does /usr/bin/mail not function correctly from within a daemon?
I appreciate your assistance

> Checked man mail but nothing that I could see...
That's because you're looking in the wrong place
mail uses your current login name combined with the domain settings for postfix, so it's postfix's configuration you need to be looking at.
Specifically:
/etc/postfix/main.cf
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# The myorigin parameter specifies the domain that locally-posted
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myorigin = $mydomain
if you just want to append your domain name.

Why do adjacent bins differ so widely in histograms?

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