Jmap histogram and [C [B [D [F [I and [J

I've been using jmap to create the memory histogram for an application and I get output that lists [C, [B, [D, [F, [I and [J for some of the class names. I know that these are arrays of some type, possibly of primitives. Is there some explanation some place of what these types are?
I've downloaded the source for JDK 5 and searched through there but I had no luck. The language or JVM spec perhaps might have some explanation?
Any clues or direction on what these types are and where I can find a good explanation would be appreciated.
Thanks in advance.

http://java.sun.com/docs/books/jvms/second_edition/html/ClassFile.doc.html
Look for 4.3.2 Field Descriptors
-kto

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Histogram and saturation in Photoshop

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I would appreciate a response.
Mail: [email protected]

Not sure I follow all the details you mention.
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Jmap: portability and safety for snapshotted process?

I'm working on tracking down a memory leak in a java application that's at the heart of my employer's business. Right now, we're restarting it periodically, and watching it closely with nagios.
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I've lost the histogram - and other adjustment woes

I filed a rather long description of this to the Aperture Feedback, but as I suspect that is a "write only" channel I thought I'd ask here (and I did review a bunch of posts with no luck)
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Aperture is such a wonderful program when it works... I've had a bunch of minor issues with the program over the past year I've been using it - but this is insane.
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Note: A small update to my post. I thought the histogram had disappeared, but upon closer inspection it is there -- but it reads as if it were a completely black image (e.g., all of the values are in the first column). Another clue...
Message was edited by: davebets

I should mention that i have NOT upgraded to iOS 5 on the 3GS and don't want to. Therefore, no iCloud on the phone.

Add ability to use raw data in the Histogram and clipping indicators

I have posted this as an ACR and Lightroom Feature Request at the Photoshop Family site.
http://feedback.photoshop.com/photoshop_family/topics/raw_data_histogram_display_lightroom _and_adobe_camera_raw?rfm=1
It was suggested I also post it here to for more visibility.
"The current Histogram display in Lightroom and Adobe Camera Raw accurately display the file image data for JPEG, PNG, PSD, TIFF file types, but not for raw files.
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http://forums.adobe.com/message/3967184#3967184
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Question about histograms and indexes

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Would appreciate some clarification on this, thanks!!!

First, the article in question doesn't say to create histograms on columns with high cardinality values. A primary key column is going to be the ultimate in high cardinality columns (each value is unique after all) but it's rarely appropriate to create a histogram on that column. It does say that that histograms are generally useful when the data in a particular column is highly skewed-- that is, different values occur at wildly different rates.
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PS CS4 histogram and floating windows

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Oops

10.2.0.4 CBO behavior without histograms and binds/literals

Hello,
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Environment:
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Thanks and Regards

oraS wrote:
As i already mentioned, that there were no historgrams i was very amazed, that the execution plan changed because of using literals.
Does anybody know in which cases the CBO includes the values in LOW_VALUE and HIGH_VALUE in its execution plan calcuation?
Until now i thought that these values will only be used in case of histograms.I don't have any references in front of me to confirm but my estimation is that the LOW_VALUE and HIGH_VALUE are used whenever there is a range based predicate, be it, the BETWEEN or any one of the <, >, <=, >= operators. Generally speaking the selectivity formula is the range defined in the query over the HIGH_VALUE/LOW_VALUE range. There are some specific variations of this due to including the boundaries (<= vs <) and NULL values. This make sense to use when the literal values are known or the binds are being peaked at.
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HTH!

Weird histogram and RAW conversion

Sorry in advance if this quesion is already out there.
I've just rebuilt my machine and noticed some really weird stuff with aperture once I re-installed the program. I'm accessing the same library with the same settings but now I get some really weird conversions of my low light photos (new and old). The really strange thing is that if I just touch a slider (levels, exp, etc) not even adjust, the image previews fine. If I check the levels and then uncheck and restart aperture the photo looks fine. When I restart again...bang back to weird photo! During this weirdness the histogram gets choppy as well. Check the examples out at this site http://homepage.mac.com/dpolly/weird/index.html the grabs are in order. By the way the export of the photo always looks fine. I hadn't seen this issue unitl re-installing the app. This leaves me with the "can I trust this program" kinda feeling. Please help.
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G5 Mac OS X (10.4.6)
G5 Mac OS X (10.4.6)

Thanks.
I just wanted to make sure I wasn't losing my mind!
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I think I'll hold out for 1.1 and hope all goes well.
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Thanks,
Dan
G5 Mac OS X (10.4.6)

Histograms and statistics

Hi
How to know the list of tables/columns where histograms statistics exists ?
Regards
Den

Hi,
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I'm trying to find info on how to tap into data from the iPhone camera. I want to develop an app that uses histogram data and to build a light meter. Can anyone help me out?

You can build your own histogram from any image. I very highly doubt you'll be able to construct anything even remotely resembling an accurate light meter as the camera's driver and/or firmware most likely already has one that is continually making adjustments before you ever get any data at the application level.

Keeping Histogram and Adjustment Panels Open together

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Thanks for that suggestion, Brett. Today I spoke on the telephone
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How AUTO stats job decides on histograms and sample size?

Hi All,
I am on Oracle 11.2.0.3 .
I have a table with 161M records. In fact it is an IOT. We are running the default stats collection job from Oracle (not even the time is changed !!).
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COLUMN_NAME                    NUM_DISTINCT NUM_NULLS NUM_BUCKETS SAMPLE_SIZE HISTOGRAM
COLUMN1                                   1          0           1   162988917 NONE
COLUMN2                                   0 162988917           0             NONE
COLUMN3                           119808000          0         254        5548 HEIGHT BALANCED
COLUMN4                                3048          0         254        5548 HEIGHT BALANCED
COLUMN5                                   1          0           1   162988917 NONE
COLUMN6                                 173          0          77        5549 FREQUENCY
COLUMN7                            43225088          0           1   162988917 NONE
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Why sample size is so small on the columns where histogram exists?
Why sample size is 100% on the columns where there is no histogram? (I am assuming NONE means there is no histogram on this column)
COLUMN6 is a really skewed column. There are actually 173 distinct values in there. How come Oracle found that correctly in such a small sample size?
Thanks in advance

rahulras wrote:
SQL> select column_name, num_distinct, num_nulls, num_buckets, sample_size, histogram
2 from dba_tab_col_statistics where table_name='TABLE1';
COLUMN_NAME                    NUM_DISTINCT NUM_NULLS NUM_BUCKETS SAMPLE_SIZE HISTOGRAM
COLUMN1                                   1          0           1   162988917 NONE
COLUMN2                                   0 162988917           0             NONE
COLUMN3                           119808000          0         254        5548 HEIGHT BALANCED
COLUMN4                                3048          0         254        5548 HEIGHT BALANCED
COLUMN5                                   1          0           1   162988917 NONE
COLUMN6                                 173          0          77        5549 FREQUENCY
COLUMN7                            43225088          0           1   162988917 NONE
7 rows selected.Why sample size is so small on the columns where histogram exists?
Because the code decided that the histogram it generated at that size was sufficiently accurate - but I can't tell how it came to that conclusion.
Why sample size is 100% on the columns where there is no histogram? (I am assuming NONE means there is no histogram on this column)
COLUMN6 is a really skewed column. There are actually 173 distinct values in there. How come Oracle found that correctly in such a small sample size?
The answer is probably that it didn't. I suspect you have enabled the approximate_ndv mechanism, which applies in the first pass for collecting simple stats, and the num_distinct in every case was therefore very close to perfect with a 100% sample size. The histograms would then have been collected in a second pass. You have only 77 buckets in the frequency histogram on column6, which means Oracle knows about just 77 values for that column despite reporting 173 as the number of distinct values. to my mind, the inconsistency between num_distinct (which should have been pretty accurate) and the number of buckets should have made Oracle collect another, larger sample size of the histogram.
Regards
Jonathan Lewis

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Hi,
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This question was posted in response to the following article: http://help.adobe.com/en_US/photoshopelements/using/WS287f927bd30d4b1f5548d97812e28a69a90- 7ff4.html

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Jmap histogram and [C [B [D [F [I and [J

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