How can someone use my phone to make an outgoing call and have it show up to network provider as my number that made the call?

Question: I made a call to co-worker this morning. While I was talking the call disconnected. When I looked at my phone it was making a call to another number, which I did not recognize. I let the call connect and a recording came on saying, in effect, that "it was not a working number". I called back my coworker and explained what happened. I researched my at&t online account and it shows the call as an incoming call from my coworker BUT he did not call me, I called him - both times. The phone number that kicked me off my original call shows up in my phone's call history list as an "outgoing" call but shows up in my online account calling history as an incoming call from my coworker. How does this work?
Comment: error in AT&T's network
Answer: There are many reasons this could have happened but there is one primary that springs to mind:

Error on Provider Network causing the disconnection and an erroneous forwarding and recording instead of a proper reconnect

This isn't that uncommon, especially during maintenance windows. It is however always startling.
Basically what happened is that you changed communication points. Usually during these times you're handed off without interruption in service by being forwarded to the new point. It's why you can make a call and it will keep in contact as you cross points.
However every now and again you make a call and the forwarding logic hits a hiccup, and instead of being forwarded correctly your phone's link to the point has gotten confused and it thinks it's supposed to make a call.
In the cases the dropped call is seen as received because the call received a forward notice... that instead initiated the call out.
To be certain though you should DEFINITELY call and confirm this was the problem with your provider. The main reason we can come to this conclusion however is that your records show and incoming call when it was actually outgoing on one record, but the correction on the other. This shouts carrier error but it's always better to get an authoritative answer form the source.
Answer: Yes, it might be possible in the India GSM Network, you may trace a call, send a SMS with others phone number, call someone using others phone number.
But, for that IMSI number of victim is required, could be possible to get using Social Engineering Technique.
Additionally, you should have a Raspberry-Pi with Dual-Antena, among which one is for signal receiving and another is for signal sending. This will create a local BTS (Base Transceiver Station) of your own in 50 meters range. In this range your may perform the above mentioned tasks.
Comment: Why did you guess he's in India when me mentions ATT?
Comment: @Sirens  that's why he wrote `it might be possible`


Tor relay and apache

Question: I am running a tor relay on my desktop (Ubuntu 14.04) as well as using the tor browser to access the internet myself. I would like to host a web site using apache on the same computer. Are there any risks in doing this? Will the relay or my web browsing be compromised?
Comment: A part of your question is answered here: https://tor.stackexchange.com/q/1699/88
Comment: Thanks for the link Jens. It seems that running a relay on the same computer as your tor browser doesn't increase your risk and may possibly be beneficial though there is some uncertainty. I haven't been able to find anything though relating to running apache and a relay on the same computer. I wonder if this has been studied?
Answer: Running a Tor relay, a Tor Browser and a web server on the same host does not make either of them more vulnerable or identifiable. But running a relay means that your IP is publicly advertised, which could get any internet-facing service on your host more 'attention' than it would get otherwise.

Tor relay and apache


What tools are out there to collect participants' browsing and/or search data as part of an experiment?

Question: I'm running an experiment where I need to collect and analyse participants' browsing and search histories. The design of the experiment is similar to an "instrumented user panel", described here:http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.104.8971&rep=rep1&type=pdf
In the classic case, participants must install some kind of logger on their computers, which collects and sends browsing data to the researcher behind the scenes. Finding such tools is where I get stuck.
I could, of course, just ask my participants to export their browsing histories and send them to me every night, but I was hoping there would be something more automated out there, with potential bells and whistles such as annotations.
Note: Please let me know if this is the wrong Stack Exchange; I must be really struggling with finding the right keywords for this...
Answer: What you are looking for a client-side JavaScript tracking. This is often done through cookies.


How exactly does convection happen when heating water? Also why does hot water/air rise?

Question: When a pot of water starts boiling, does that mean that the top surface of the water was heated repeatedly by convection? Meaning that it was initially at the bottom of the pot, then it rose up to the top when heated, then circulated back down and then up again until it reached 100C? (Is that what actually happens or is it just a way to explain how boiling happens?). Also, is there another way to explain why hot water/air rises other than "it became lighter because of it's lower density"?
Answer: The idea that water heated at the bottom of a pot rises to the top and returns to the bottom by convection is correct. The convection happens because hot water has a lower density and thus rises up to the surface where it cools and sinks down to the bottom again. When water starts boiling there is the additional effect of the formation of water vapor bubbles that have a much stronger buoyancy than hot water. Thus these water vapor bubbles by their fast movement to the top where they leave the liquid also produce a strong upward water current leading to an increases convection in the pot.
Answer: To answer your first question, depending on the circumstance around the water, yes convection is what heats the pot.
To your second question: Hot objects rise because of what 'heat' is. How hot object is depends on how fast the molecules/atoms which make it up are moving, with the hottest objects having the most movement and the coldest having the least (which is why we have absolute cold temperature, but not hot). So the atoms that are moving around more quickly push against others with more force, causing hot objects to expand. Biggest objects push others out of the way, but, having nowhere to go, the hot objects (air and water) rise to the top. This is a GENERAL rule with some exceptions, i.e. water, which, due to molecular structure expands when it freezes.
Comment: It is worth mentioning that water is an exception only between 0°C and 4°C.


Is UK income which is exempted in UK taxable in India

Question: I am a Indian citizen working in UK on a work permit. My salary in Uk is 36000 pounds.I have heard that in UK salary of 10500 pounds is exempted from tax and my company is paying tax on the remaining salary. So will I have to pay tax on the amount of 10500 pounds in India which is exempted in UK?
Answer: Assuming that for the given financial year, 1 April to 31 March you have stayed more than 182 days out of India, you will be classified as non-resident Indian, NRI for tax purposes.
If you are NRI, you don't have to pay any tax in India.
If you are not NRI you have to pay taxes on the full salary 36,000 GBP in India as per tax rates.


Can't type ' / ' (slash) after the letter ' l ' (ell) in Terminal, makes 'l' with stroke character 'ł'

Question: When I type any word ending with an 'l' (ell, like "local") and then press the / key, the 'l' is replaced with another symbol and the slash, '/', is omitted. How can I deactivate that function?
Comment: This looks like a rendering bug rather than an actual issue. Does it actually affect the content of your command?
Comment: @LukeTaylor  But he gets a "no such file" message, so it is affecting the content, the sequence l/ is being changed to a totally different character.
Comment: Ah, ok. Maybe not then.
Comment: It seems this could be specific for your user account; could you try creating a new user to see if it happens there, too? If not, then I'd suggest having a closer look at your .bashrc and .bash_profile, maybe you're having problems with bash completion? Also: what keyboard layout are you using?
Answer: This looks like the behavior of some very old Mac fonts (Palatino was one of them) where you could make the character l with stroke (used in Polish and elsewhere) by typing such a sequence.  Try changing your font.  If this is in fact the cause of the problem,  you should get rid of the font that does this, which should not be on any modern mac.
Comment: [More details can be found in this post on Apple's support forums.](https://discussions.apple.com/message/12103226#message12103226) The font composition was created to make it easy to enter `ł` or `ø` characters by typing `l` or `o` and then `/`, but this is not always what you want. I had it in my browser, where `HTML/CSS` was rendered `HTMŁCSS`
Answer: Seeing that you use white on black, I take it you use the "Pro" profile (unless you duplicated it or created a fresh new one).
I would look into Terminal's preferences and check the used encoding and other options.  If there are differences with, let's say the "Basic" profile, try to see if using that profile is behaving the same or behaves as you would expect.  If it is as you expect it, see about changing your used profile more and more to the comparison.
Answer: I had this same problem because I had an old Monaco font in ~/Library/Fonts/. I was able to disable the old font with FontBook, and the issue was resolved.
Note that I had the same issue with a number of leftover old fonts. I was able to clean them all out in FontBook with "Look for enabled duplicates..."
Answer: This looks to me like a rendering bug rather than a feature. I would try increasing the font size on your terminal.
Comment: No rendering error, only happens inside terminal and I can't execute the comand I want since de l and the / merge making another character


How can I disable Photos Agent on High Sierra (10.13.4)?

Question: Looks like Photos Agent is running in the background. I'd like to dedicate this machine to file services and not run unnecessary processes. How can I disable "Photos Agent" at boot time. I'm hoping to free up resources like RAM and CPU.
Answer: From personal experience, I can say that letting it finish once (it processes photos in the Photos app) makes it end forever.
But you can speed up that process by removing iCloud photos syncing.
Comment: Thanks for the reminder about iCloud Photos. This was the culprit. I hadn't loaded any photos into Photo.app.
Comment: However, this is not a perfect solution, because it relies on reasonable user behavior, rather than taking control of the system feature, at the admin level.
Comment: Absolutely this isn't perfect. Depending of your needs, you may want to take control of all iCloud and other user friendly processes that may interfere with your file services needs. One of the answers I found looking around was killing the unnecessary deamons.


DIFFERENCE BETWEEN ONLINE AND OFFLINE SHIPPING METHOD

Question: I am working on a custom Magento module. I am facing some issues to debug the code and one question that comes into my mind is that what is the difference between offline and online shipping method. Try to elaborate Magneto docs explain Offline Shipping here  but I have to understand it more deeply
Answer: You don't need to set the shipping module to the module for online shipping, so you don't have to get API. Also, a tracking number is not given by your module. It's alloff-line shipping.
Comment: Can you please explain a bit more?
Answer: The online shipping methods are those which actively consume the API of a 3rd party system owned by a shipping services provider in order to fetch the shipping cost and the information regarding the parcel's delivery tracking in Magento.
So I would say that if you are not intending to integrate Magento with the platform of a shipping carrier, then you can develop the module as an offline shipping method by implementing and keeping all the logic inside Magento.
There are situations where you already have the shipping price logic in Magento, but the ERP/ or another system which handles the orders will integrate with the shipping carrier system and receive the tracking number of the order. This, in my opinion, is also offline shipping method scenario, even if there is a way for Magento to receive back the tracking number from the ERP so that the client can track their orders.
Comment: Thanks @diana for this information
Comment: you are most welcome!


how to set the author of the feed item to the author of the feed source in feed importer?

Question: I have created a feed importer.
I do not know how to set the author of the feed item to name of the original author of the feed?
Is there any method to do it?
Or will apply any patch?
Any patch for this functionality will be welcome.
Answer: I had a hard time getting this to work.

My current settings work.

Feed Importer
-attached to Feed (content type)
-RSS parser
-Mapping: Description to Description, Title to Title, Item GUID to GUID (Unique), Item URL to URL (Unique), Published Date to Published Date, and Feed Node: User ID to User ID.  It is important to have a unique identifier or you get duplicate imports.

The Feed Itself
-Set "Authored By" to a Drupal user on your site.   This lets you custom the user. Create a new user if necessary. I created a couple dummy users just to get their names to appear as feed item authors.
Comment: are u sure "Feed Node: User ID" can be used when config author is set to anonymous? I this issue is still active @ DO https://www.drupal.org/node/1414080 https://www.drupal.org/node/652180
Answer: Here is the up to date code. Put this code into a custom module to achieve the desired result:
<?php

/**
 * Implement hook_feeds_preserve
 */
function MODULE_NAME_feeds_presave(FeedsSource $source, $entity, $item) {
  if ($entity->type == 'WRITE_NODE_MACHINE_NAME_HERE') {
    global $user;
    $entity->uid = $user->uid;
  }
}

?>

Comment: node_machine_name is  feed node to which import is attached or node that are being imported?
Answer: The Feeds module keeps track of the feed that was used to import each node. All you need is a nodeapi('presave') implementation that will pass the feed's author on to the node being imported.
A snippet like this should do it:
function YOUR_MODULE_nodeapi(&$node, $op, $a3, $a4) {
  if ($op == 'presave' && !empty($node->feed_node_item)) {
    $feed_node = node_load($node->feed_node_item->feed_nid);
    $node->uid = $feed_node->uid;
  }
}

Answer: Aaron Kreider gave the right answer. Put it in short, in mapping, set the source "feed node: user id", set the target "user id"; and the node author will be defined as the feed author.
It took me a while to find out this and fulfilled my work. Some people mentioned that you need to do coding, I guess they are talking about previous versions, or perhaps they didn't notice the easy solution.
Answer: Importing a CSV file and setting the Author / Authoring field for the node based on a header / column from the CSV file.
Using Drupal 7 with feeds-7.x-2.0-alpha8

In my CSV file I have a column with the heading Author.
I added a new user with permissions to edit the appropriate content. The user's name came from the Author column in my CSV file. (You must add the user to Drupal before importing the CSV file.)
In: Home » Administration » Structure » Feeds » Foo, I set the source field to Author and the target field to Username. (Foo is the name of the custom importer which I created.)
I imported the CSV file.
Success!


What is the most natural form of Vitamin D supplementation?

Question: I'd like to take cod liver oil or something similar to boost my vitamin D levels (which are low). I want something totally natural. Is there any way to take cod liver oil without feeling the reported awful taste of it ? If not, what other alternatives are there ?
Comment: At what latitude do you live? It may be possible to get your vitamin D up by just spending 30 minutes outside per day.
Comment: This is a nutrition question which are off topic according to the new [FAQ].
Answer: Your best 'natural' options will probably be...
UV exposed mushrooms

...after one hour of UV light exposure right before the mushrooms were harvested, the vitamin D2 content in a serving of mushrooms rose to more than twice the FDA daily value. The effects were even more pronounced if mushrooms were exposed after harvesting: Monterey Mushrooms found increases as high as four times the FDA daily value per serving after only five minutes of UV treatment.

Exposure to sunlight with no sunscreen

Sunscreen absorbs ultraviolet light and prevents it from reaching the skin. It has been reported that sunscreen with a sun protection factor (SPF) of 8 based on the UVB spectrum can decrease vitamin D synthetic capacity by 95 percent, whereas sunscreen with an SPF of 15 can reduce synthetic capacity by 98 percent

The more surface area that's exposed the more vitamin D is produced. The darker your skin the less you absorb. Tanning beds will also work but not nearly as well as real sunlight because they primarily output UVA light (UVB is needed for vitamin D synthesis).

Vitamin D3 is made in the skin when 7-dehydrocholesterol reacts with ultraviolet light of UVB type at wavelengths between 270 and 300 nm, with peak synthesis occurring between 295 and 297 nm.

Cod liver oil, while having a lot of vitamin D may also come with other risks. Including...
Hypervitaminosis A - Overdose of vitamin A

Although hypervitaminosis A can occur when large amounts of liver (including cod liver oil and other fish oils) are regularly consumed, most cases of vitamin A toxicity result from an excess intake of vitamin A in the form of vitamin supplements.

Environmental toxins such as mercury, polychlorinated biphenyls (PCBs), dioxins

Some urge caution when taking cod liver oil and other fish-based supplements since they may contain elevated levels of toxins such as mercury and PCBs found in fish.

If you overdo it, you could be doing more harm than good.
Answer: Here you go.
http://www.globalhealingcenter.com/natural-health/10-foods-containing-vitamin-d/
Comment: Welcome to Fitness and Nutrition Beta! Whilst this may theoretically answer the question, [it would be preferable](http://meta.stackexchange.com/q/8259) to include the essential parts of the answer here, and provide the link for reference.
Comment: Vitamin D rich food is perfect for the long term, but for a short term fix I need something way stronger !


Are fictional languages on-topic here?

Question: I mean something like Klingon or Quenya when I say fictional languages. Are questions about these languages on-topic for this site?
Comment: Could you expand on how you will use such learned language? Most people learn languages to gain some level of functional usage (speech communication/writing/reading) in our daily lives. Of course in the end it depends on what the question is.
Comment: I won't personally be using it, but I imagine it could be helpful for anyone attending some sort of convention or writing a person a poem or story in the fictional language.
Comment: Well I am wondering if this is more of an entertainment/literature related topic, unless someone is actually going to communicate with others using such languages.
Comment: Duolingo considers Klingon a language, why shouldn't we?
Answer: I say yes. Fictional or not, they are still languages right?
Though these languages are purely fictional, questions can still be about the learning of these languages. I would expect some differences in the questions asked as they are not actually used in real life but can be learned by eager fans. Instead of the languages people actually use, I think we are flexible enough to introduce an interesting and exciting new topic to our site: fictional languages.
Now if this happens, we must make some restrictions on these languages as these questions are new and we just entered public beta, thus the need for borders and rules to all of our different types of questions.
Answer: Fictional languages are pretty similar to real languages, with the main difference being that there may not be a population or country that speaks the language. It's still gonna have grammar structures, vocabulary and maybe even a character set.
The only situation that I could see leading to trouble is if one of these languages is incomplete; how are you going to learn a language that hasn't been fully designed? However, this might not be even be a problem, it may even make to be an interesting question.
We could always use the constructed-languages tag if we need to, but I suppose the use case for that would be pretty limited.
Comment: It was just an example tag, but thanks @Gwenn, I'll edit it into the question :)
Answer: I believe the answer to this question is the same as the answer to this question:

Our site is "Language Learning", it's about the learning a language, so if language specific questions are about learning the language, it would be on-topic.
Questions shouldn't be about the language's spelling/syntax/semantics/etc., they should be about learning it.
Some examples of off-topic questions (feel free to edit more in):

What does <insert quote from a book> mean?
What is the origin of <insert idiom here>?
When do you pronounce <insert letter here> in <insert language here>?

  That said, questions which apply to the process of learning a specific language, should somehow apply to a broader range of "similar" language. I'm not saying that all questions falling under this should be left open, if it has some other flaw such as being primarily-opinion based, it should be closed.

In other words, the on-topicness of the question is not based on the language, but on the question.
If the question is about learning, your target language can be Spanish, Esperanto, American Sign Language, or Klingon. It doesn't matter.
There will be very few (if any--I can't think of one now) questions that are unique to learning fictional/created languages. If such a question exists, though, it ought to be permitted, granted it is about learning.
Comment: @ANeves: Updated. Next time, feel free to edit yourself :)
Comment: I can't, the edit button is disabled for me: `Suggested edits are not allowed on non-tag-wiki posts on meta sites.`
Comment: Also, in your edit: `idom` should be `idiom`.
Answer: Gee I hope so. I study toki pona and Esperanto, most of what I get out of the experience is learning how to learn a language using an exemplar with a level of difficulty way less than Spanish or Dutch.
Comment: Esperanto is a constructed language, not a fictional (to me meaning derived from a work of fiction) language.
Comment: @fi12 You should edit your question so that the distinction is clear.
Comment: I'm going to assume that the OP is asking in the most broad manner possible about non-natural languages. The hobbists that care about this have an extensive taxonomy for varieties of non-natural languages. I can't imagine the answer would be different for Lojban, Esperanto and Tolkien's Elvish, or the numerous derivatives of all three.
Comment: No, I'm referring to fictional languages - languages created for fiction. Esperanto is a constructed (or auxiliary) language, as is Lojban. A fictional language is something created for a book, movie, etc.
Comment: @fi12 The [help for "on-topic"](https://languagelearning.stackexchange.com/help/on-topic) has a [link to constructed languages](https://languagelearning.meta.stackexchange.com/questions/201/are-fictional-languages-on-topic-here/202#202) that points to a different (not relevant?) answer here; so presumably one of these answers should address that subject, such as this answer does. Otherwise the help should be edited to point to a different Q&A. --- We now have a specific site for the topic: https://conlang.stackexchange.com/
Answer: It's hard to understand what you mean by a "fictional language."  If a language exists, it exists.  If people speak it or write it, it is real.  Perhaps you mean natural (occurring naturally in the culture of a people) vs. synthetic (invented for a book or a movie or for fun or other purposes).  Any way you slice it, languages are languages and should be fair game on this site (assuming they're meant for communication between humans and humans and not between humans and microchips).

Are fictional languages on-topic here?


In Memoriam: Leonard Nimoy

Question: It is my sad duty to inform the community that Leonard Nimoy has beamed up for the last time. He will truly "Live long and prosper" in all our memories.
RIP
Comment: Oh starless night of boundless black.
Answer: We are assembled here today to pay final respects to our honored dead. And yet it should be noted, in the midst of our sorrow, this death takes place in the shadow of new life, the sunrise of a new world; a world that our beloved comrade gave his life to protect and nourish. He did not feel this sacrifice a vain or empty one, and we will not debate his profound wisdom at these proceedings. Of my friend, I can only say this: Of all the souls I have encountered in my travels, his was the most.... human.
Comment: A fitting eulogy
Answer:
Answer: RIP Spock.
Answer: Dif-tor heh smusma ...

Live long and prosper in Vulcan, according to the New York Times. If this is wrong, I'm sure some Star Trek expert will rip my head off ... er, I mean, will let me know.
Comment: [It appears to be](http://en.memory-alpha.org/wiki/Vulcan_language) from [the first movie](http://en.memory-alpha.org/wiki/Star_Trek:_The_Motion_Picture)
Answer: William Shatner's tribute: the following image is a mosaic made up of pictures of Star Trek fans doing Vulcan salutes.
Comment: This is truly incredible.
Answer:
Comment: Video unavailable
Answer: I can't think of an actor who death affected me more. I remembered him well from first-run episodes of Star Trek, the few times I was up late enough to watch and of course from watching countless reruns.
He was easily 50 percent of why ST was such a standout -- an alien (or half-alien) who had really depth of character, whose people and culture were thought out in exquisite detail. Spock was easily in the top ten of all television characters, perhaps top 100 or even higher of all characters in fiction -- there, I said it. And it is hard to imagine someone else in the role -- Nimoy was brilliant.

In Memoriam: Leonard Nimoy


Max ram for Acer Aspire one D255

Question: I can't seem to find what the max amount of ram is supported on the Acer Aspire one D255. It came with 1gb, and I see that most netbooks support up to 2gb.
Answer: "". The D255 will support 2GB of RAM (there's a single slot inside) but it's not especially easy to open up the casing. Happily you'll only ever do it once.""
http://www.slashgear.com/acer-aspire-one-d255-review-28110853/
Answer: While the Slashgear site certainly seems to suggest that a single RAM slot leads to no more than 2GB of memory, DDR3 RAM is available up to 4GB on a single module and could in the future go as high as 16GB on a single module.
Therefore I'd say the question is still open. Perhaps Slashgear is wrong or just sloppily worded. Perhaps there is a 2GB limit but if so it's not because a single DDR3 slot can't have more memory plugged into it.
UPDATE
It turns out the Intel Atom N550 is limited to 2GB of RAM, so the processor is the limiting factor rather than the number of RAM slots.
Answer: your acer aspire d255 is most likely a 32bit system. If its windows 7 starter it will only allow you to have 2gb of physical memory. You can change that by changing settings in your boot menu though.
Comment: How do you change the boot menu setting?

Max ram for Acer Aspire one D255


Translated articles of Fatou and Julia

Question: Is there any English translation of the 1918-1920 Memoirs of Fatou and Julia on the iteration of rational functions?
Comment: An analysis and comparison of the work of Fatou and Julia on holomorphic dynamics is contained in the book by Michele Audin "Fatou, Julia, Monetl,,,". It is quite complete, and this book has been translated into English.
Comment: I posted my response below. Thanks for getting interested.
Comment: Rosa translated Julia's Grand Prix memoir, but only [opening pages](https://www.emis.de/journals/AMEN/posters/poster0171.pdf) are available online. There are detailed summaries and historical context in [Early Days in Complex Dynamics](https://www.google.com/books/edition/Early_Days_in_Complex_Dynamics/gpbNAwAAQBAJ?hl=en).
Comment: I remember that there was a project of translating Julia papers, and I was even asked to proofread some translations. But I don't know what happened to this project and whether translations were posted on Internet. Concerning Fatou, there are no translations that I know about.  I recommended to the authors to translate Fatou, since on my opinion Fatou's papers are much more valuable, but for some reasons they did not want to, and were only interested in Julia. But this was long ago.
Comment: Now I recall something about the project mentioned in my first remark. The name of translator was Alexandro Rosa, and here is his translation of the first 10 pages of Julia: https://www.emis.de/journals/AMEN/posters/poster0171.pdf Apparently the project was abandonned.
Answer: I was pointed to this chain of messages and I would then like giving you my version of facts. The translations project was the very very early version of the contents that ended up in the book I published for AMS in the end of 2011. It started for my personal knowledge and fruition.
I can't recall exactly how the files of Julia's memoir translations spread online, as facts date back to more than twenty years ago. This was not my concern at all in then times as I was aware that the quality was not worth the circulation, and honestly I would have liked them to be removed when I discovered they had been put online (a few years later). Anyway I could not know how to do that, since I could not find out whom to call for. I just have a bare recollection that I shared'em with somebody, for pure show. Things went out of my control.
And yes, professor Eremenko is right: I suspended the work on translations. Or maybe I gave up. But there were some valid motivations: first, due to the above book. Second, at the time I was not sure they might really be of interest for publishers or readers. Most of them are original memoirs or articles, written in French. Which I presumed that most mathematicians, and amateurs, are able to read it. I thought they might have not been of use for anybody- Moreover, I am not a native english speaker, so I was not quite confident in spreading them, since they need revision before being made public.
You would like to know that Julia's are not the only translations I did. I have much more material:almost all Julia's works up to early 1920, including the memoir of 1919-21, where Julia discovered the so-called "lines of Julia", inherent to the neighboring behavior about essential singularities and, as you know, quite close on Julia set. There would be only the memoir about permutable maps to be translated.
In addition, there are also almost all Fatou's works on iterations, except the long memoir of 1919-20, the one you mentioned in your messages. That I did not at the time, because of the original plan changed. Again, the translation of the two articles by Samuel Lattès appearing in Comptes Rendus of 1918 (about Julia set filling the Riemann sphere) and the three works by Hubert Cremer, where he explored the dynamics around non-linearizable indifferent points of irrational kind.
The original plan behind the next-to-be aforementioned book consisted in releasing a collection of those early articles that would have covered nearly fifty years of holomorphic dynamics, spanning from Schroder and Koenigs, up to Fatou, Julia and Cremer. Including Bottcher's production: either his thesis of 1899 (compiled in German) and mostly the later production around 1904, which anticipated the discovery of so-called "Fatou-Leau's flower". (By the way, Ernst Lémeray accomploished it too shortly before Leau's thesis). Bottcher went to a thorough analysis of this same question, pretty much interesting on my viewpoint. The original work is in Russian, and I know the contents thanks to a native Polish-Russian speaker who translated some of those pages.
In conclusion, I gave up because I would have liked joining a task force including a native speaker / mathematicians (German for Cremer, Russian for Bottcher at least). Take care that the original format of my files is still MS Word, so they need be turned into LaTeX first.
I am currently busy with the submission of a new history book on holomorphic dynamics, that covers some of the topics I resumed above. But I am open to resume this translations project, if there would be margins of interest. According to the above, it naturally goes that I would be very prone to any form of cooperation and coordination.
Thanks for showing interest. Hope I have fulfilled your curiosities.
Feel free to write me to firstname.lastname@example.com
Comment: Did you consider arXiv? It is Latex friendly and automatically generates pdf. Some authors post their translations there, e.g. [Aycock](https://arxiv.org/abs/1808.02841) and [Bistafa](https://arxiv.org/abs/2105.03319). Clicking on the poster's name one can see all of their posts, so all your translations will be gathered in one place. Of course, that makes them freely available, so I am not sure if you want to do that when there is a prospect of publication.
Comment: Btw, yes, 40+ years ago most professional mathematicians could read English, French, and German, of necessity. This seems no longer true. So, yes, for the future, translations into English are very useful, even if in a kinda-pathetic way. :)
Comment: Thank you for sharing. I suspect that most English-speaking mathematicians, and especially amateurs, are unable to read French. At least, not well enough to follow complex mathematical arguments. I do not know how realistic it is to find a publisher for your translations, or to assemble a task force, but if it does not work out I hope you will find a way to make them public. Even raw translations in Word, maybe converted into pdf, would make the works accessible to many people who cannot read them today and benefit from the original flow of ideas. Perfect should not be the enemy of good.
Comment: I understand that the amount of pages would be too huge for a printed publication. It would be nice then for some academic istitution to grant some free web space, that I could manage and progressively fill in with translations. My plan would be to turn MS word format into LaTeX and the generate the PDF. I feel more confident with LaTeX nowadays: when I first compiled the translation, I didn't know this tool yet. It's my standard for producing PDF.
Comment: Thanks for suggesting, but at the moment ArXiV looks too rigid to me. I had troubles with permissions in the past, because I needed someone crediting me, my reputation and my uploads.
I would like having an all-in-one solution .... I mean to a web page  where I can mantain contents on my own,; lists, downloads, texts by means of a FTP connection.
Besides translations, there's some additional material that I would like sharing and that it is not compatible with publishing on ArXiV.
Comment: Thank you for your comments. I have written some of my thoughts below.
Comment: I meet your point. Sometimes translations could represent an aid for those being not able to find out the original historical resources. Anyway, thanks for feedback, I hopefully expect to put all my translations out with additional diagrams and comments by the end of this year
Answer: Before posting my thoughts I would like to thank everyone for contributing to this inquiry and express my sincere appreciation for Mr Rosa's answer.
I have read parts of two books on the history of complex dynamics

A History of Complex Dynamics
From Schröder to Fatou and Julia
Early Days in Complex Dynamics: A history of complex dynamics in one variable during 1906–1942

I have to say it was quite a joy reading through their chapters, and I found them very helpful and informative for a plethora of aspects regarding the theory itself.
Before continuing further though, I need to say that I am not an expert in the field, as I am about to begin my PhD on holomorphic dynamics in autumn this year. So, my knowledge about publishing is minimal at best, if nonexistent. Furthermore, I am neither a native English speaker, nor a French one, but I manage to understand a little bit of the latter.
Last year I completed a Master's Thesis on the subject, but there were no faculty members in my university studying complex dynamics, (my thesis committee was comprised of some external experts on complex dynamics though). Therefore, I had to learn the theory on my own, and at the time, I was finding the books available a little difficult to crack through their line of thought and motivation behind some concepts, especially the first time I encountered some ideas. This was the case with the Leau-Fatou theorem for example, where on the other hand Fatou's original Memoir provided much needed (for me) explanation and details.
Furthermore, it strikes me, how much these men understood the subject they were studying. One can find evidence for that on pages 158 to 170 of Julia's online available Memoir, for example. Of course, nowadays with the help of computers, we can easily visualize Julia sets, but I find the thought that Fatou and Julia suspected the complexity of the objects they were dealing with quite appealing.
In my opinion, these Memoirs could serve as an auxiliary introduction for the subject and translating them into English could help popularize the field and help lower the "entry barrier" for students, as both Fatou's and Julia's Memoirs contain many worked-out and very detailed examples, something that many of the books I encountered partially lack, and provide strong motivation for many concepts now standardized in the theory. Moreover, I agree with Mr Rosa's remark that comments and graphics would constitute a great enhancement.
I understand Mr Rosa's objections to making the translated documents public, but as Conifold pointed out, "Even raw translations in Word, maybe converted into pdf, would make the works accessible to many people who cannot read them today and benefit from the original flow of ideas", and I have experienced this benefiting myself.
In conclusion, I believe that such a collection of translated documents could greatly enhance the learning experience, and the study of foundational ideas, and could significantly contribute to the historical aspect of the field. I was puzzled when I began studying complex dynamics and I could not locate a translation of such influential publications, they remind me of Klein's work on the Icosahedron or the Fricke-Klein books.
I would be very pleased if I could be of any help in such a project.
I would like to see your thoughts on those points as naive as they may seem from someone who does not have significant experience with such matters.
Comment: Thanks for appreciating those two books. Actually, the first entry was instructive for me as well, and was the first reason why I got in touch with the author, Daniel S. Alexander, and we started long and efficacious conversations, which eventually turned into the co-authoring of the second entry. Please, read my post below.
Answer: This is a longer comment rather than an answer to the  question  specifically about Fatou and Julia papers. Having been given green light by Sandro, let me add some more details about his project of "releasing a collection of those early articles that would have covered nearly fifty years of holomorphic dynamics, spanning from Schroder and Koenigs, up to Fatou, Julia and Cremer". Sandro and I exchanged emails in 2013-2014 concerning my joint work with Stanislaw Domoradzki on the life and achievements of Lucjan Emil Boettcher. In one such exchange I learned about Sandro's project described in his answer above. Wishing to contribute, I translated (from Polish to English) Boettcher's 1898 article in several parts: ``Zasady rachunku iteracyjnego"
[Principles of iterational calculus , Prace
Matematyczno Fizyczne, vol. X (1899 1900), pp. 65-86, 86-101, v.
XII(1901), p. 95-111, v. XIII(1902), pp. 353-371.
This paper contains most of Boettcher's pioneering ideas in holomorphic dynamics. His 1904 memoir in Russian largely overlaps with it. My translation is almost complete, except typesetting of some elaborate but repetitive formulas in Part III.  I feel confident about its accuracy (I am a PhD mathematician, a native speaker of Polish, and I have been living for nearly half of my life in the USA). Sandro helped me with reproducing Boettcher's graphics. This translation could be  viewed as a part of his project.   It was never published or posted online, because I had no idea what would be a good venue for it (posting on ArXiv not as an author of the contents is tricky, and I do not have a Web page). And (as Sandro already said) there was little external interest. While I do not mind  sharing the files,  a word of warning is in order. Boettcher's works should be appreciated for the wealth of the ideas they contain, but they suffer from lack of rigor.
I pointed this out on many occassions, e.g. here.
Failures in math
Comment: Margaret, thanks for getting in. I am confident that a good project is starting to come up and develop, thanks to different contributors. I am trying to arrange things to go that way. At this point, old opinions that I may have reasonably held twenty years ago would be senseless nowadays.
Answer: I will embark on the translation of Fatou's memoir and hopefully get it done by the start of next summer. I am quite confident of it, thanks to the recent re-study for a new book project.
Take care that one such project would be of interest for experts and beginners; hence it's not just about pasting my rough translations into a PDF and share it. Syntax, language, appearance must be worked out.
To Prelude, I posted my email address in the first comment at the top. Write me, in order to check whether we can meet on some point.
Comment: Sandro, I added an answer about Boettcher's translation being available, as promised.

Translated articles of Fatou and Julia


Spacemacs: paste into minibuffer

Question: Is there a way to paste something into the minibuffer?
For example if I want to eval-expression and paste something in there neiter C-v or (obviously p) will work? There has to be a way.
Comment: Have you tried `C-y` (which would be the Emacs standard key) ?
Comment: I thought I had. That works. Thanks.
Answer: C-y does work, but you can also paste into the minibuffer from the default register using dotspacemacs-emacs-leader-key instead of dotspacemacs-leader-key, in which case you can use: leaderre" or leaderrereturn.
Alternatively, you can search and paste the contents from any register: for example leaderre phrase you remember.
Personally, I've just set dotspacemacs-emacs-leader-key to an easily accessible key chord and used it everywhere instead of dotspacemacs-leader-key.
Comment: I've installed the git layer in spacemacs. When running maggit-clone I'm given a minibuffer asking for the repository URL. `C-y` pastes the `"` buffer for me, but if I try `SPC-r-e-"` in the minibuffer it just says "Whitespace is not allowed here" followed by typing `re"` Any suggestions?
Comment: @bobpaul I gave incorrect keybindings--thanks for the heads up. I've corrected my answer above.

Spacemacs: paste into minibuffer


Vba program in average

Question: I would like an help on vba since I never worked nor have any experience in programming and needed it to analyze a huge amount of data.
I have 3 columns,

A is time
B is positions
C is pulses (image)

What I really want is to obtain in another cells (like range.value) the average of the positions that are obtained with 0 pulse and then go to 80 pulse and do the same and then go to the next 0 and do the same, and so on...
Is it possible to obtain also the value of time at which the pulse 80 occurs in each case?
Thank you!
M
Answer: I do not understand what you seek. I think I understand something about the data but not enough to guess what you want done with it.
However, if someone did understand what you seek, I do not believe they would help much by writing a macro for you.  It might solve today's problem but you would not be ready for tomorrow's problem.
You must learn VBA.  Search the internet for "Excel VBA Tutorial".  There are many; some good some less good.  Try a few and see which fits your learning style.  Alternatively visit a good bookshop or library and select an Excel BVA Primer.  Again many to chose from.  The advantage of a library is you can take a couple home to try before buying the one you prefer.  I like to have reference books on my shelf so that was my approach.
It will not take long to master the basics and that investment in study will quickly repay itself.  I believe you will have real trouble understanding any bits of useful code you find here or elsewhere without knowing the basics.
You will have to design your program yourself.  My guess from your description is that your data looks like:
Time  Positions  Pulses
xxxx  yyyy         0
xxxx  yyyy        10
xxxx  yyyy        50
xxxx  yyyy        80
xxxx  yyyy         0
xxxx  yyyy        20
xxxx  yyyy        60
xxxx  yyyy        80
xxxx  yyyy         0
xxxx  yyyy        30
xxxx  yyyy        40
xxxx  yyyy        50
xxxx  yyyy        80

You do not tell us about the format or contents of the Time and Position columns.  I believe you have a number of sub-tables with the first row having 0 Pulses and the last row having 80 pulses.  You do not tell us if there are a fixed or variable number of rows per sub-table.
If a fixed number of rows per sub-table, a simple For-Next loop will be sufficient:
Const RowsPerSubTable As Long = 5
Dim RowStart As Long
Dim RowEnd As Long
Dim RowLast As Long

For RowStart = 2 To RowLast Step RowsPerSubTable
  RowEnd = RowStart + RowsPerSubTable - 1

  ' Process sub-table RowStart to RowEnd

Next

With a variable number of rows per sub-table you will have to search for the 80 pulses row.  That will be a little more complicated but not much.
The above is very basic VBA.  Any tutorial or primer will introduce For-Next loops at an early stage.
I hope the above convinces you that your requirement is not difficult to achieve and that with a little study you can do most of the programming yourself.
If you have a problem, come back with your code and explain why it is not working as you wish.  That is the type of question this site specialises in.

Vba program in average


Is it a coincidence that the length of the body of a violin is pretty exactly one fifth of the wave length of its lowest note?

Question: The standard body size of a violin is 35 centimeter in length. Its lowest note is G3, which has a wave length of 175 centimeter, five times 35. 35 cm is the wave length of B5, which is a major third above G. Is this a conincidence or did anybody calculate this when designing it?
Comment: The second half of your question is not a coincidence: a major third can be seen as being defined by being five times (ignoring octaves) the frequency of the lower note, and thus its wavelength would be five times shorter. A major third has a frequency ratio of 5/4.
Comment: @00 or rather one fifth as long.  The phrase "n times shorter" (or smaller, or less, etc.) is inconsistent and confusing.  For that matter, so is "n times longer" (or greater, or more, etc.).  It's better to use "shorter" and "longer" for additive comparisons, and "as long as" for multiplicative ones.
Answer: It is a coincidence, because there is no simple relation between the wavelength of sound in air, and the wavelength in the structure of the instrument (either in the wood or the strings).
The fact which is critical to the sound of a violin is the lowest vibration frequency of the air inside the body, which is about an octave higher than the lowest note. That depends mainly on the volume of the air and the cross section area of the F holes. The exact shape of the instrument (and the shape of the holes) are not so critical.
For a "half size" instrument the volume is smaller which would increase the frequency of this air resonance, but reducing the area of the F holes decreases it.
Comment: @CamilleGoudeseune the volume/cross section ratio is more like an ocarina or other vessel flute https://en.wikipedia.org/wiki/Vessel_flute . In linear flutes the length of the pipe is in fact half the wavelength of the lowest mode of vibration. Linear flutes can be overblown to multiples of the fundamental frequency; it's harder to do that on a vessel flute
Comment: Kind of, sort of, like the volume of air in a flute and how many finger holes are open?
Comment: Note that I recall a recent study to find the optimal geometric shape for sound holes that showed that violin F holes actually came empirically pretty close to the optimal. Might not be a "critical" part, but it helps.
Answer: Yes, it's coincidence, mostly.  Consider that 200 years ago  A was maybe 415 Hz, not 440 or 444 Hz.  It is "mostly" true that there's no real value to a resonant chamber more than 1/4 wave of the lowest tone desired, but there's also a lot of art bordering on black magic to create a body which produces a "pleasant" resonant strength at all wavelengths (including overtones) in the normal playing range of the instrument.
It might be interesting to do that same calculation for a few dozen other bowed string (or for that matter, plucked) instruments.  However consider that half, and quarter, and even 1/8 size celli and basses are available for child players.  Some tonality may be lost but overall they serve their purpose.  For that matter, there are certainly "non-standard" fullsize violins & cellos & basses.
Comment: When calculating - be aware that a 'half-size' instrument is actually nowhere near half-size!
Comment: @tim, good point.  I know that but should have made it clear that actual physical measurements on instruments should be done.
Comment: At a tuning of 415 Hz the respective length would be 37 cm, still a lot closer than other string instruments are to this ratio. That begs the question if other instruments could be improved by approximating this length.
Answer: Being EXACTLY 1/5 is a coincidence (see Carl Witthoft answer). But the musical instrument size (or generally everything made to produce sound) is pretty much related to the wavelength of the sounds it produces. The laws of physics dictate that you cannot efficiently radiate sound (or any other waves, say, electromagnetic waves) using something much less than 1/4 of the wavelenght.
That's why cello and bass are bigger.


Is MSN chat encrypted or not? If not how can I make it encrypted?

Question: How can I force pidgin to use only encrypted connections when using MSN chat? I'm on Ubuntu 10.04
Answer: It isn't encrypted, you can use the off-the-record plugin that's available as a third-party plugin for Pidgin. FYI Off the record is available for Gaim, Adium and also as a compiled binary for Pidgin on Windows.
Answer: I'm not sure if MSN is encrypted but if you can use and get your buddies to use the Off the Record plugin your communications will be encrypted and also not understandable to potential intercepting parties.


My Macbook Pro's headphone jack is buzzing/humming

Question: I have an audio problem with my new macbook pro 2017.
If there is an audio playing my headphone jack starts to buzz (headphones unplugged). When I stop playing audio, after a short period of time, it stops humming. When I plug the headphones and start playing the audio, headphone jack is not buzzing/humming. This is super weird. It looks like macbook for some reason thinks that it has plugged headphones even when it doesn't
Does anyone know how to deal with this problem?
Comment: would you please specify how it is humming?
Comment: Something like this but much much quieter https://youtu.be/abOwU5B2Zwk
Answer: Ok, I have fixed this problem by reinstalling the OS.


Should a Jew who doesn't believe in G-d observe the commandments?

Question: In an earlier question, I asked if it was a commandment to believe in G-d. As with so many areas, there were differing opinions. Some of the respondents claimed that there would be no point in being Jewish if one did not believe. While I disagree with that view, surely we all recognize that there are Jews who do not believe who, nonetheless, have varying levels of observance. Irrespective of whether or not one sees a point to doing so, should a non-believing Jew observe (the other) commandments?
Comment: "Should," from whose point of view?
Comment: From a Talmudic/Midrashic point of view.
Comment: Like Alex has so finely quoted, the observance of mitzvos would certainly lead the individual onto the right path and eventually into the belief of G-d. I find it hard to believe that you could do all the mitzvos and never come to that conclusion.
Answer: In a word, yes. The Midrash (Eichah Rabbah, intro. 2), paraphrasing Jer. 9:12, states:

הלואי אותי עזבו ותורתי שמרו, מתוך שהיו מתעסקין בה, המאור שבה היה מחזירן למוטב
"Would that, even if the Jewish people abandoned Me, they had kept My Torah! By being involved with it, the illumination in it would bring them back to the right path."

Or as the Talmud (Sotah 47a, et al) puts it:

לעולם יעסוק אדם בתורה ובמצות, ואף על פי שלא לשמה, שמתוך שלא לשמה בא לשמה
"A person should always be occupied with Torah and good deeds, even if not for the right reasons, because from doing it for the wrong reasons he will come to doing it for the right ones"

- and goes on to illustrate this with the case of Balak, the Moabite king who offered numerous sacrifices with the improper intention of convincing G-d to allow the Jewish people to be cursed, yet who ended up being the ancestor of Ruth (and, through her, of King David and eventually of Moshiach).


Historical statistics

Question: Do you know if historical statistics from area51 are available? For instance, how many users we had yesterday and how many the previous day?
Answer: Yes... sort of.
Now that beta sites are part of the Data Explorer, it's possible to extract nearly all the Area 51 statistics for nearly time period you care to look at.  Here's questions/day for Open Data:

You'll have to construct your own queries for the other numbers.  Remember that since the data dumps are weekly, the Stack Exchange Data Explorer (SEDE) results will be missing up to 7 days of data.
The data that isn't readily available is traffic.  For those interested, Quantcast does publish visitor data, but I believe it's measured differently than the numbers used for Area 51.

Historical statistics


Understanding VLAN Tagging for Network Segmentation

Question: I've been reading up on network segmentation and the use of VLANs to enhance security and network management. However, I'm still a bit unclear about the concept of VLAN tagging. Can someone please explain what VLAN tagging is and how it works in the context of network segmentation? Also, are there any best practices or common pitfalls to be aware of when implementing VLAN tagging in a network?
Answer: VLAN tagging is a way to label network traffic so switches can identify which Virtual Local Area Network (VLAN) a packet belongs to. It's crucial for network segmentation, improving security, and optimizing network management.
Here's a quick rundown:
Ethernet Frames: When devices communicate in an Ethernet network, they exchange data in frames. VLAN tagging adds a tag to these frames, typically in the 802.1Q format, to indicate the VLAN.
Switch Configuration: To use VLAN tagging, configure your switches. Specify which ports are part of specific VLANs and define each VLAN's ID. The VLAN ID goes into the frame's tag.
Isolation and Segmentation: Switches examine the VLAN ID in the tag. They only forward frames to ports belonging to the same VLAN, keeping traffic separate. This enhances security and network organization.
Best Practices:
Document your VLAN setup for clarity.
Implement access controls and firewalls for security.
Regularly review and adjust your VLANs.
Common Pitfalls:
Misconfiguration can cause traffic leaks or isolation problems.
Don't create too many VLANs; it complicates management.
Monitor VLAN traffic to spot issues.
Hope this clears things up! Feel free to ask if you need more details.
Answer: VLANs logically divide switches into separate, unconnected switches. Frames in one VLAN cannot be sent to an interface for a different VLAN. In order to connect to a device that communicates with multiple VLANs (routers, switches, etc.), there needs to be a method to distinguish which frames belong to which VLANs so that the frames can remain separate for each VLAN.
To accomplish that, ethernet was extended to insert a tag into the ethernet header (Cisco originally did this with an encapsulation of the frame, but the industry decided on inserting tags into frame headers). The tags are inserted into the frame headers on links that carry multiple VLANs. You can have one VLAN that is not tagged, and it is distinguished from the other VLANS on the link by not having a tag, and it is called the native VLAN.
Access interfaces that go to end-devices (PCs, printers, etc., which do not normally support VLANs) are assigned to a particular VLAN, and they do not insert tags into the frame headers. Trunk links are links that carry multiple VLANs frames, and frames are tagged on trunk links (with the possible exception of a native VLAN).


Delete some matches of an incremental search

Question: I use C-s for sequential searching. When I want to delete the current match, backspace will go to the previous match instead. How can I delete the current match?
Comment: What do you mean by "delete a match"? Do you want to delete the buffer text that is found? If so, and if you want to be queried about whether to delete *each* such match after the cursor, then use `query-replace(-regexp)`, not Isearch.
Answer: It seems, M-x query-replace is one of the way to achieve what you are looking for. Just replace by an empty string.
Comment: @Tim You should read the documentation sometimes.
Comment: You can directly jump from `isearch` to `query-replace` with `M-%`, and the from string will be filled with the search term.
Comment: is it sequential? I need to check if I want to delete each match.
Comment: @Tim: it is probably faster to try it out than to wait for a response. ;-)  But yes, it is sequential.  It will run from `POINT` to the end of the buffer, stopping at each match in sequence.
Comment: You call `M-x query-replace`, then you give the string you want to replace, the replacement string, and you hit enter. you'll have to confirm by 'y' for each occurence found. Hitting '!' will replace it all, without asking for confirmation. Why not give it a try? :)
Answer: If you want to delete the current match and nothing else, the following would do:
(defun isearch-kill-current ()
  (interactive)
  (delete-region isearch-other-end (point)))

(define-key isearch-mode-map (kbd "<deletechar>") 'isearch-kill-current)

It doesn't interrupt the search, just deletes the currently selected match and lets you proceed with your next forward C-s or anything similar.
Answer: Isearch has no built-in command to act on the current match as a unit.
You can press RET to stop searching and edit at the current point location, which is the end of the current match (or the beginning if searching backwards). But there's no automatic way to go to the beginning of the match.
The following little function exits isearch, like RET, and additionally sets the mark at the beginning of the match (the point is at the end; swap beginning and end when searching backwards). I demonstrate how to assign it to M-m.
(defun isearch-mark-current-match-and-exit ()
  (interactive)
  (isearch-exit)
  (push-mark isearch-other-end))
(define-key isearch-mode-map [?\M-m] 'isearch-mark-current-match-and-exit)

Once you're done editing, you can resume the previous search by pressing C-s C-s.
Alternatively, to delete some occurrences, replace them by the empty string. As suggested by Nsukami _, run query-replace, enter the string to search, then enter the empty string as a replacement. Type y or n for each match depending on whether you want to delete it or keep it.
If you started from incremental search, you can switch to a query-replace operation by pressing M-% during the incremental search. The current isearch string will be used as the string to replace.
Answer: To expand on the last paragraph of @Gilles' answer:
You can turn an ongoing isearch into a query-replace search.

As you're doing isearch, if you decide you would like to erase some
entries, simply hit M-% (which is Emacs's binding for
query-replace)
and it will transform you ongoing isearch into query replace.
The current search term will remain the same and you will be prompted for a replacement.
Hit RET for no replacement.
Hit y on the the matches you want to erase, and n on those you don't.

It will start asking at current match, so it's a great tool to use midway through an isearch.
Comment: Gilles actually included that as the last paragraph of his answer, albeit in briefer form.
Comment: @JonathanLeech-Pepin True! I missed that.
Answer: If you use library Isearch+ then you can do this:

Hit C-SPC while searching, to tell Isearch to select the last search hit as the region.
C-SPC actually toggles option isearchp-set-region-flag, which when non-nil selects the last search hit visited.
Hit C-x o while searching, to pause Isearch; do whatever you want (e.g. replace the selected last search hit); and then hit C-M-c to resume Isearch.
C-x o opens a recursive editing session, where you can do anything you like (including
search for something different).  Using C-M-c closes the recursive editing session and resumes the search (from the current position where you hit C-M-c).
Use C-M-RET to perform a specified action on any search hit you visit. Just repeat C-M-RET to continue visiting and acting on subsequent search hits.
The default action is to replace the search hit.  This means you can use C-M-RET to replace search hits on demand.  Provide a prefix arg to C-M-RET at any time to change the replacement string (the default is "", which just deletes the search hit).  This means you can provide different replacements for different search hits.
With a negative prefix arg, C-M-RET changes searching itself (e.g. C-s) so that it automatically replaces whenever a search hit is visited. With a positive prefix arg N, you replace the next N search hits. With a zero prefix arg (e.g. C-0), you replace all remaining search hits.
(To use a prefix arg with Isearch you must set option isearch-allow-prefix or isearch-allow-scroll to non-nil.)
On-demand replacement (with C-M-RET) can use query-replace-regexp-style replacement. That is, you can use \&, \=\N, \#, \,, and \?.  You can use C-M-` while searching to toggle whether such constructs should be interpreted or taken literally (as plain text).

See the Isearch+ doc for more about replacement during Isearch.


Sim free vs Verizon iphone

Question: I'm looking at the new iPhone SE and was wondering if you're going to pay in full for the phone ($499) is the sim free phone different than the Verizon carrier specific one? I read somewhere the sim free had 1 extra band (so maybe that is better if you want the flexibility to change carriers later)?  Verizon is my current carrier, and I'll start the phone there but could see moving somewhere later if the deals are worthwhile. Once I put a Verizon sim (which the Apple Store will give you for free) in the sim free one, is it the same as the Verizon specific one (and conversely if I get the Verizon specific phone and take out the sim for another can it go to any GSM network)?
Answer: The only difference is cost.
Now that we've moved into a contract-free phone era, service providers, like Verizon, will offer to let you make a payment plan instead of paying for the phone upfront. In the end, the cost is the same as the SIM-Free version, but the Verizon version only works on Verizon until they unlock it.
Conclusion: Verizon iPhones are physically the same as SIM-Free iPhones, but Verizon has more control over the Verizon model.

Bonus note:
If you are considering getting an iPhone and are on AT&T or T-Mobile, the SIM-Free version will be a better deal because only the SIM-Free, Verizon, and Sprint models support CDMA, which is needed for those networks.

Sim free vs Verizon iphone


Low water pressure on refrigerator water dispenser

Question: I have a Whirlpool Refrigerator model ED5VHEXVB00 and right now I have a low water pressure coming out of the water dispenser. The water filter needed to be replace this month and the light just turned red so I bought one and replaced it thinking that this might have something to do with the problem.  After replacing the water filter I still have the same problem.  Water pressure is very low and is making very thin ice cubes.
Comment: If you remove the filter completely do you still have low pressure (you may need to catch the water from the filter location, rather than the dispenser). Filters, even new ones, usually reduce the pressure as they filter.
Answer: Many times the problem you are describing comes from a saddle valve a small valve that punches a hole in the existing pipe. These valves are notorious for getting plugged and leaking. The best fix would be to install a T  And a shut off valve at the location because in a few months or years most saddle valves start leaking.


Why is は pronounced as わ when used as a topic particle?

Question: The particle は is pronounced similarly to わ (unlike the rest of the ハ行 kana) when used as a particle; why is this? What historical shifts went on to cause this irregularity?
Answer: In Old Japanese (probably before 800 BC), the pronunciation of 「は」 (and indeed the entire ハ行) was PA, but it later changed to FA (more accurately, [ɸa], with a bilabial fricative), and this was the common pronunciation at least up to the 16th century (we know this since early Portuguese transliteration of Japanese words use the letter F where we would use H today).
While the phoneme /p/ became /f/ in isolation or in the beginning of the word, it remained /p/ after a the consonant ん and in between vowels (except in some compounds such as 魔法 まほう). This led to a verb such as 買う (Old Japanese: 買フ kapu) to be read as kau (<- kawu) in Positive form and kawanai (instead of kapanai) in negative form, and also for the particle 「は」 (which regularly appears after a vowel) to be normalized as WA.
Up to the spelling reform of 1946, Historical Kana Usage (歴史的仮名遣 れきしてきかなづかい) was still the standard, so 買う was still written 買フ (Katakana was more commonly used for Okuriganaback then), and 買わない was 買ハナイ. That changed in the reforms, along with many other archaic and confusing spelling, so much that the current Japanese spelling is almost completely phonemic. Only a handful of traditional spelling quirks remained, and using は for the particle that is pronounced WA is one of them.
Comment: Very interesting, I had no idea about the /p/ and /f/ phonemes, just about the ハ行/ワ行 merge-thing - but that explains why the semi-voiced is /p/ and the ふ is /fu/ - I have learned something today. \(^o^)/
Comment: @Kafka: Yeah, it does explain all the voiced/unvoiced mess in ハ行. :)
Comment: Great answer, especially with the historical notes. Would love to see more of this kind of thing!
Comment: @Dave: Thanks. Glad to know I haven't studied Linguistics for nothing. :)
Comment: Is there a list of these traditional spelling quirks that still remain somewhere?
Answer: The sound 「わ」 used to be written は in old kana usage in some cases. Old kana usage was much more irregular than it is nowadays. The old way of writing has kind of stuck in some words.
It's the same thing with the readings for the particles へ and を too - the modern sound 「え」 used to be written as へ in some cases and 「お」 as を. Of course, pronunciation varies and sometimes you can hear a clear difference between お and を for instance, but in all words besides the particles the old pronunciation differences have disappeared as time has passed.
Comment: So this is a kana shift, not a phonetic shift?
Comment: @bdonlan: Yes, in many words the kana changed but the pronunciation stayed more of less the same. The particles just got stuck in the past.
Comment: Actually, it is both. See my answer :)


Goral Oscillators

Question: I am studying Colpitts oscillators with one single JFET. These circuits are well known. However, I experienced that I sometimes have start-up problems. I know this is related to the loop gain being too low. I the book 'Practical Oscillator Handbook' by Gottlieb I found the Goral oscillator. I modified my circuit and found out that the Goral oscillator works much more stable and reliable than the ordinary Colpitts. However, besides the mentioned book I didn't find any other sources about those Goral oscillators, this is why I think these are not very well known or they must have some drawbacks I didn't find out so far. After whom are they named, what is the theory behind them and what are their pros and cons?
Answer: The goral oscillator used as a VCO: -

Taken from here.
Adding an emitter follower just boosts the drive current to the centre tap point of the capacitors in what would otherwise be a standard colpitts oscillator. I've used this design in a capacitance probe based on the probe feed line being a tuned half wave resonant transmission line. However, it wasn't something that I knew about beforehand but something that was developed to solve a problem indicated below.
Because the t-line can present a very low impedance (especially at high temperatures of +1000 degC) the extra drive capabilities of the emitter follower make this a good solution.
I have no idea why it is called this name but, after a quick google I think it is named after a guy called Pierre B. Goral.
The main drawback is that because they use two transistors in cascade, the highest frequency the pair can oscillate is limited to the low to mid hundreds of MHz (currently).
Comment: @SpehroPefhany Spinning blades in an aircraft turbine - some probes (and don't ask me what they are made of cause I don't know) will do 1300 degC
Comment: Just out of curiosity, what the heck were you measuring with the capacitive probe? 1000°C is a bit low for steel. Ceramic processing?
Comment: You didn't by any chance know Tony Williams did you? I think they're Titanium in the compressor and nickel-iron superalloys in the combustion chamber, but that's a dim memory.
Comment: No, his name doesn't ring a bell but as I work with a few ex rolls Royce folk from the derby plant I might ask them on Monday.

Goral Oscillators


Historical volatility from non-uniform samples

Question: The way I compute historical volatility is that I take two parameters $dt$ and $T$, get a list of stock prices with the step of $dt$ over the window $T$ (so $T/dt+1$ samples in total), compute $T/dt$ returns from this prices, compute their sample standard deviation, and scale using $\sqrt{dt}$ to annualize it.
In case I have non-uniformly sampled data, i.e. $dt_1\neq dt_2 \neq \dots$ I wondered whether I can compute annualized historical volatility without resampling?
Answer: What I would do :
Step 1. Calculate $V=\sum_i \frac{\Delta P_i^2}{dt_i}$
Step 2. Annualize V. $V_a=\frac{V}{T}$
Step 3. Find $\sigma = \sqrt{V_a}$


how to add css reference to a specific subites shapoint 2013

Question: I want to apply a custome look and feel for different subsites.
My question is how to add css reference to specific subsites?
Answer: That depends.
If the site has the Publishing Feature enabled, you can link to a custom CSS file in Settings > Master Page.
If the Publishing Feature is not enabled, you will need to edit the Master Page and inject your link to the custom CSS.
All this has been asked many, many times before and there are lots of web sites and tutorials explaining the finer details.


Geometrical isomerism in cycloalkenes

Question: Why doesn't cyclohexene have a cis-trans isomer whereas cyclodecene has one?
Is strain a factor?
Answer: You simply can't make a transoid molecule of cyclohexene because there is not enough "length" in the carbon chain.
I don't know if it is "strain" per se--but a putative transoid cyclohexene would have extraordinarily exotic bonding arrangement--thus being very high in energy.
Answer: Yes, in cycloalkenes with of 7 or less carbon atoms, the high ring tension is a prohibitive factor, but in higher cycloalkenes it's not that great so they can show the geometrical isomerism.

Geometrical isomerism in cycloalkenes


Is there a practical maximum size for a space capsule returning to Earth?

Question: Assuming I need to get a large cargo or a lot of people safely to Earth's surface in one go in a single-use capsule of the Apollo CM / Soyuz descent type but larger, and assuming that the capsule is already in space (so launching it probably isn't an issue), what might limit how large the capsule design can be? Would there be any particular advantages to a larger capsule, again assuming that launch isn't a consideration?
Comment: If there is a limit, it's quite large. At least Chrysler thought so when designing their entry for the Shuttle design competition. https://i.imgur.com/jhEoE.jpg
Answer: Let us consider the square cube ratio. If we enlarge an Apollo CM capsule by a linear factor of 2, its surface scales with factor 4 (the square of 2) and its mass and volume scales with the factor 8 (the cube of 2).
But for the hot phase of reentry we need the same path length in the upper atmosphere. So the deceleration (g force) should be the same as for the original capsule size. To decelerate 8 times the mass, we need 8 times the drag force. But drag force scales by the square of the diameter, not by the cube. So we need a longer reentry distance to slow down, but the height of the atmosphere is still the same as for the original Apollo capsule.
If the cone shape of the capsule should be the same, we need a capsule with the double diameter and height, 8 times the volume but only 4 times the mass of the original Apollo capsule. But this would require an extreme lightweight construction and would limit the possible payload too much.
If we would manage to slow down to the speed for a parachute deploy at the necessary height, we have another problem. When we use 3 parachutes with the double diameter, the weight of the capsule should be only four times but not eight times the original weight. So we would need 6 instead of 3 parachutes with the double diameter. Or 3 parachutes with 2.828 times the diameter (the square root of 8).
But both sets of parachutes will have more than 8 times the mass due to the larger area and mechanical stress. So for a very large capsule the necessary parachutes will be too heavy.
Comment: I agree. And we don't really know if it would have worked.
Comment: So limit the massive part to a large disc (or lens shape ;) with a light-weight cone on top if you need some passive stabilization.
Comment: The very large Chrysler SERV capsule proposal used jet engines, not parachutes.
Comment: Using jet engines instead of parachutes does not help when the first hot phase of reentry fails because the height atmosphere is not enough for slow down.
Comment: Chrysler believed they could make it work, enough to submit a serious proposal. https://en.wikipedia.org/wiki/Chrysler_SERV
Comment: If the Chrysler SERV would have worked, would it work too if scaled by a factor of 10? I can't tell where the limit is, but there must be a limit.
Comment: @aml But when "a large disc (or lens shape ;) with a light-weight cone on top" is used, the diameter of this reentry body will be too large for launching it with a rocket. The diameter should be smaller than the first stage lower end diameter.
Answer: @Uwe's answer is great, and presumably to the question

Is there a practical maximum size for a space capsule returning to Earth?

the answer there is pretty much "yes" based on current capsule technology. Space planes and "rockets with flippers" can be larger perhaps, but @Uwe's square-cube argument would still apply.
I'll address the last bit:

Would there be any particular advantages to a larger capsule, again assuming that launch isn't a consideration?

and my answer is "not in terms of ease of reentry", and for the same square-cube reasons. The smaller reentry capsules for automated sample return don't need to push things to the same extreme limit in terms of heat shield and parachutes, and the lower mass allows for mid-air retrieval.


How does the referral system work?

Question: I don't understand how the referral program works even after reading everything about it. Do I only get the 500 CC if the referred person subscribes within 14 days, or if I just refer the person? And do I get 500 CC for every month that referred person subscribes, or is it just one time?
Answer: There are two types of referrals:

You, as a subscriber, refer a past or present subscriber who has never been referred before.  (The page says they can't have been referred within the past 90 days, but unfortunately it doesn't work if they've ever been referred period.)
You, as a subscriber, refer someone who creates an entirely new F2P account with your referral link.

In my experience, #2 rarely works (the system is not very reliable).  But when it does, they just get a "Jumpstart Bundle" with a few utility items.
In the case of #1, they get a "Preferred Friends Bundle" with 7 days of free sub time and some utility and cosmetic items.
As for what you get: In the case of #1 for a current sub, and in both cases if they subscribe within 14 days, you get 500 Cartel Coins (one time).  For every month they subscribe after the first month, you get 100 Cartel Coins.
More details: http://www.swtor.com/info/friends
My profile has my referral link for anyone who wants a referral.
Answer:
Previous Subscribers who have been unsubscribed for 90 days or more are eligible to participate in the Friends of SWTOR program. If they participate, they cannot be referred again for 90 days.
If you're a new player, opt-in for email communication from Star Wars: The Old Republic is required

For returning Subscribers, rejoining the Game through the Friends of SWTOR program offers exclusive benefits including seven days of subscription level access, a Preferred Status Bundle with special customization and convenience unlocks, and one Complimentary Character Transfer for the lifetime of the account.
For new players, the Jumpstart Bundle includes:

1x Quick Travel Pass – A single-use pass to use your planet's Quick Travel network without a cooldown. When consumed, it grants your character a single-use pass with a duration of 60 minutes.
5x Minor XP Boost – Increases experience gained from all sources by 25% for 1 hour. This Boost will not stack with other Experience Boost consumables.
1x Inventory Module – Adds 10 additional Inventory slots. Using this item immediately grants additional inventory space, to a maximum of 80 slots.

For previous Subscribers, the Preferred Friends Bundle includes:

Unlock: Inventory Module – Adds 10 additional Inventory slots. Using this item immediately grants additional inventory space, to a maximum of 80 slots.
Unlock: Crew Skill Slot – This item will grant an additional Crew Skill slot to a maximum of 3.
Customization Control: Character Display Titles – Unlocks access to display Character Titles that you have earned. Show off your accomplishments and gain recognition with this unlock.
Customization Control: Unify Colors – Unlocks the ability to unify the colors of your equipment. This cosmetic feature. This cosmetic feature allows you to determine your character's look.

How does the referral system work?


accidentally applied color profile

Question: I accidentally applied a color profile to my display in the color application in system settings. I was wondering if any one knew how to revert this, as there is no revert option in the window. I am currently running 13.04 any suggestions?
Answer: Go to the color settings page, then click on the monitor and it should show you the profile in the right. Click on that profile and then remove it with the prompt. It should remove the profile immediately, but if not try logging out or rebooting.

accidentally applied color profile


Some characters in Ether addresses have changed to capitals after upgrading Mist

Question: I recently upgraded Mist from 0.3.9 to 0.5.0.  I have noticed that the capitalisation of some of the characters in my public address have changed. Is this normal?
Answer: A basic backward compatible address check-sum mechanism was introduced into Mist (https://github.com/ethereum/mist/pull/201), whereby based on the address itself, some of the characters are capitalized while others are not.
If all the characters are uppercase or lowercase, Mist assumes that it's a non check-summed address for backward compatibility. On the other hand if some are upper case and some are lowercase, then Mist verifies the capitalization against how itself would capitalize that address. If they match, the address is considered valid.
More info on this reddit post: https://www.reddit.com/r/ethereum/comments/470s3q/vitalik_made_a_very_clever_backwards_compatible/
Answer: I don't think it actually matters. The capitalization is meant for the purpose of optional checksum. The Checksum mechanism is encoded in the address variation that consists capitalization. It is impossible to check the validity of a particular address if it only contains letters in lowercase. However, either variation will work fine as an address. As a matter of fact, you could even randomly capitalize or lower-case the letters and it will still work just fine! ( But don't capitalize the prefix "0x")
In case you are interested, this is how the checksum works:
Start with the lowercase address and the prefix 0x is removed.
sha3 hash the string of letters
change the capitalization of the address letter corresponding to the nth letter of the hash following the rule below
0/1/2/3/4/5/6/7 → Lowercase
8/9/a/b/c/d/e/f → Uppercase
Basically, you sha3 hash your original address with 0x removed, and examine each Nth character of the sha3 hash result. If the Nth character is from 0-7, the corresponding Nth character in your address is in lowercase. On the other hand, if the Nth character is from 8-9 or a-f, the corresponding Nth character in your address is in uppercase.
Source:
https://cryptoverze.com/question/are-ethereum-addresses-case-sensitive/


El Capitan causing built-in trackpad and keyboard to freeze intermittently

Question: I have a MacBook Pro 15" Early 2008, 2x 2GB RAM. Since upgrading to El Capitan including update 10.11.1 the built-in keyboard and multitouch trackpad freeze intermittently for about 4 seconds randomly at least once every 60 seconds. Booting from an external drive with Yosemite or Mountain Lion doesn't exhibit this issue so the hardware is fine. Using a bluetooth Magic Trackpad in El Capitan also works fine. I've reset PRAM and SMC. If I don't type or touch the built-in trackpad, interacting using only the Magic Trackpad then there are no stalls and no Console error messages but when using the built-ins at random intervals at least once every 60 seconds the keyboard pauses and loses all keystrokes entered during the interval, and the pointer freezes then eventually snaps to a new location. So, the system is unusable with El Capitan.

Have reinstalled El Capitan 10.11.1 twice after reformatting the internal HD. Disk Utility reports no problems with the drive.
No third party software, hardware or kernel extensions are installed,
either at the system or user level - LaunchAgents & LaunchDaemons are
empty.
The only Login Item is iTunesHelper (unchecked). This appears to be the default.
It's a pure, plain and simple default Apple install onto the
reformatted OEM internal HD.
Interestingly this issue even occurs when booting the 10.11 Recovery
environment, and during the El Capitan installer.

Running in normal user mode with the Console open displays the following messages every time a freeze occurs, which you can deduce is filling up this log:
<code>11/1/15 7:57:04.000 PM kernel[0]: AppleUSBMultitouchDriver::_deviceGetReport - DeviceRequest returned error 0xe00002cd (interface 0, reportID 0x0)
11/1/15 7:57:04.000 PM kernel[0]: AppleUSBMultitouchDriver::handleSuspend - SuspendPort returned error 0xe00002e2.
11/1/15 7:57:06.000 PM kernel[0]: AppleUSBMultitouchDriver::handleReport - not in path binary mode, received 0x44 data packet of length 54
11/1/15 7:57:20.000 PM kernel[0]: USBF:    7969.165    IOUSBHIDDriver(AppleUSBMultitouchDriverNoShim)::RearmInterruptRead  returning error 0xe00002d8 (device is not ready), not issuing any reads to device
</code>
Any suggestions on what else to try or investigate to debug this? It's as if the Apple native IOUSBHID or multitouch driver shipping with El Capitan is incompatible with this (aka my) older MBP. If it didn't still work fine when booting with the earlier OS versions I'd think it was faulty hardware.
Answer: 2 GB of Ram is not enough. make it at least 4GB or even better 8GB, easy to do and cheap. It should be the exact specs. Look at OWC or Crucial website.
Comment: Sorry, my bad - it's 4GB. I actually typed '2 x 2GB' and didn't notice it lost the first 3 keystrokes. Thanks for the suggested retailers. I'm not sure this 1260 era Mac can access 8GB but you inspired me to check the tech spec and Apple states 2GB, which seems optimistic but 4 puts it above that bar.


Can't uninstall an app

Question: I downloaded a locator app not thru google play and after turning off all permissions, it still in my applications.
Comment: Turning off all permissions wouldn't uninstall an app. Clicking on uninstall would do. Are you saying you can't do it? Which application, device and Android version are you using?
Comment: You can't uninstall a system application without root permissions. root permission may voids your warranty, and system apps are built-in app for device, which you see out of the box / first boot.
Answer: Have you tried using safe mode?
If not, then try it. I, myself had a similar problem. Using safe mode, I uninstalled it easily.
If you dont know, how to use safe mode, search on google how to enable it on your device.

Can't uninstall an app


In Drupal 7, how do I create a custom rules event for any and all file entities?

Question: I'm having trouble creating a small module to add an Event scenario to Rules using the Rules API.  Basically, I'm creating a rule that should detect to see if certain fields of a file entity have certain values upon saving that file.  Then, if the conditions are met, the action is to change the URL path alias of /video/ to point to the newest video file in my system (file/[fid])
But I'm getting stuck even creating the new Event to even work.  My code below does succeed in making it appear in the Rules event list, and then when setting conditions, the Data Selector exposes the correct file fields.  But, when I set a very simple condition or even no condition, my action does not fire.
(A bigger aside: shouldn't the Rules module come pre-packaged with functionality for dealing with file entities?  There are plenty of events for nodes, users, and comments, but nothing for files.)
So, what is wrong with my code below?
/**
 * Implementation of hook_rules_event_info().
 */
function rules_extended_rules_event_info() {
  return array(
    'rules_extended_rules_event_file_insert' => array(
      'group' => t('Entity'),
      'label' => t('After saving a new entity'),
      'module' => 'rules_extended',
      'variables' => array (
        'file' => array ('type' => 'entity', 'label' => t('created entity')),
      ),
    ),
    'rules_extended_rules_event_file_update' => array(
      'group' => t('Entity'),
      'label' => t('After updating an existing entity'),
      'module' => 'rules_extended',
      'variables' => array (
        'file' => array ('type' => 'entity', 'label' => t('updated entity')),
      ),
    ),
  );
}

Answer: You can't just declare hook_rules_event_info(), it just tells rules about an event type, but you still need to invoke that event.
To invoke a declare event, use rules_invoke_event().
Example
/**
 * Implements hook_entity_insert().
 */
function rules_extended_entity_insert($entity, $type) {
  if ($type == 'file') {
    rules_invoke_event('rules_extended_rules_event_file_insert', $entity);
  }
}


How we can select multiple sizes of configurable product from product details page?

Question: How we can select multiple sizes of configurable product from product details page? Also, Can we add configurable product different size prices simultaneously in Cart?
Comment: Did you make any progress with your question?
Answer: You can't, not with configurable products. But if size is your only option for the product, grouped products might be a better option. They provide a quantity input per option.
You can read more on how to create grouped products here: http://www.magentocommerce.com/knowledge-base/entry/tutorial-creating-a-grouped-product
Comment: I am using color and size options, any advice for this?
Answer: I am not sure how you actually code this, but I have used an extension. As a for example only, this one, although there are many others if you search for

magento configurable products grid
Answer: With the drop down list, it's very difficult to add configurable product different size prices simultaneously to cart as your requirement. Therefore, you need to find another way to display configurable products which can show all simple products of this configurable product and then customers can choose quantity for each one.
Some kinds of display that you can consider are a grid table or a matrix form. All supports showing children products in a convenient way to add multiple products to cart at one time.


Can I use blender as a photo and video viewer?

Question: I want to know If I can use blender as a photo and video viewer?
Like If I have a photo on my computer I just have to press "open with" blender and blender automatically open on the UV image editor if it is a photo or on the video editor if it is a video.
If not can this be done by a script or something?
Comment: a suggestion : associate these types with a shell script which launch blender with the appropriate python script  based on the file type
Comment: I dont know what is the shell script is,can you explain?
Answer: Blender can be a useful image viewer for some formats like multilayer OpenEXR. I just expanded a bit on Chebhou's answer by creating a python script that calls blender, I expect this can be used on any *nix platform included OSX and possibly even windows.
The script that gets called or set as the application to open image files is -
#!/usr/bin/env python3

from subprocess import call
from sys import argv
import os

sdir = os.path.abspath(os.path.dirname(argv[0]))

calllist = [
    'blender',
    '--factory-startup',
    os.path.join(sdir, 'blend_image_view.blend'),
    '--python',
    os.path.join(sdir, 'blend_open_image_file.py'),
    '--',
    ]

# add the args we get as filenames
calllist.extend(argv)

call(calllist)

The factory-startup and blend file can be removed from the list of options sent to blender. I have blender setup to start with a window that fills two monitors, that doesn't work as well when used as a simple image viewer. I also setup a start file that has two simple layouts for image and movie viewing, leaving a window clear of any excess.
The main working script I adjusted a bit to handle multiple files. When multiple movies are opened I have them in separate channels, with all but the first video muted. I really don't think blender is a good choice for video viewing, this could be improved by adding a way to extract frame rates and resolutions to setup blender to match, which doesn't work well if you open multiple videos with different frame rates and sizes.
import bpy
from sys import argv
import os

# change these two values to match screens names available
# UV Editing
blenderImageScreenName = 'ImageViewer'
# Video Editing
blenderMovieScreenName = 'MovieViewer'

acceptedImgFiles = ['.bmp', '.cin', '.dpx',  '.exr',
                    '.hdr', '.jpg', '.jpeg', '.jp2',
                    '.j2k', '.png', '.rgb',  '.tga',
                    '.tif'
                    ]
acceptedMovFiles = ['.avi',  '.flv', '.h264', '.mov',
                    '.mpeg', '.mpg', '.mp2',  '.mp3',
                    '.mp4',  '.mkv', '.ogg',  '.xvid'
                    ]

fileStartIdx = argv.index('--') + 2
numFilesToOpen = len(argv) - fileStartIdx
showAreaType = 'image'
curChann = 1

for i in range(numFilesToOpen):
    filename = os.path.abspath(argv[fileStartIdx + i])
    ext = os.path.splitext(filename)[1].lower()

    if ext in acceptedImgFiles:
        bpy.ops.image.open(filepath=argv[fileStartIdx + i])
    elif ext in acceptedMovFiles:
        # while we will open video files, blender isn't the best option here
        # When opening multiple videos, each video is imported into a new track
        # tracks after the first will be muted to prevent a terrifying
        # mess of multiple audio tracks
        # end frame is set to the longest video track imported
        # frame rate is left default and will need to be adjusted for each video
        nc = bpy.context.scene.sequence_editor.sequences.new_movie(name=argv[fileStartIdx + i],
                filepath=os.path.abspath(argv[fileStartIdx + i]), frame_start=1, channel=curChann)
        if bpy.context.scene.frame_end < nc.frame_duration:
            bpy.context.scene.frame_end = nc.frame_duration
        # I expected new_movie() to import video and sound
        # but that doesn't happen so we also add sound from the same file
        nca = bpy.context.scene.sequence_editor.sequences.new_sound(name=argv[fileStartIdx + i],
                filepath=os.path.abspath(argv[fileStartIdx + i]), frame_start=1, channel=curChann+1)
        if curChann > 1:
            nc.mute = True
            nca.mute = True
        curChann += 2
        showAreaType = 'video'
    else:
        print("Don't know what type of file this is -",filename)

if showAreaType == 'image':
    bpy.context.window.screen = bpy.data.screens[blenderImageScreenName]
    # make first image active
    for area in bpy.data.screens[blenderImageScreenName].areas:
        if area.type == 'IMAGE_EDITOR':
            area.spaces.active.image = bpy.data.images[0]
else:
    bpy.context.window.screen = bpy.data.screens[blenderMovieScreenName]

Save this as blend_open_image_file.py to match the filename set in the first script.
The list of extensions can easily be extended.
I thought I would keep a copy of this on github which also has the blend file mentioned above if anyone thinks it can be improved.
Comment: When I open the image he give me a cmd screen that write some line and close again,what am I doing wrong.
Comment: most likely you didn't add the shebang line that I left out - the first line of the script should be `#!/usr/bin/env python3`
Comment: Still the same,what should the call script format be?and should I set a path or something before doing anything?
Comment: You probably have to enter the full path to blender in the first calllist item, on osx that would be something like `/Applications/Blender/blender.app/Contents/MacOS/blender`
Comment: I am using windows 10,I put blender path instead of "blender",but it is still not working.what should the file format be for the call script?
Answer: This is not for OSX ( i don't have access to one ) but the concept is the same as on Windows OS:

create a folder that contains two files myscript.bat and import_file_script.py
assign the file types ( that you want to open with blender ) to be opened by this script ( RMB->Open_with->choose_default_program   and select the .bat file )
myscript.bat is a batch script ( on OSX shell/apple-script ) and in this file put the following lines :

@ECHO OFF

SET script=%~dp0import_file_script.py
SET ext=%~x1
SET filename=%~f1
SET blender="C:/Program Files/Blender Foundation/Blender/blender.exe"

%blender% --python %script% -- %ext% %filename%

and in the python script file ( named : import_file_script.py )
import bpy
import sys

bpy.ops.wm.console_toggle()

argv = sys.argv
ext = argv[argv.index("--") + 1]
myfile = argv[argv.index("--") + 2]

if ext in ['.png','.jpg','.jpeg']:
    bpy.context.window.screen = bpy.data.screens['Image Viewer'] # or just ['UV Editing']
    bpy.ops.image.open(filepath=myfile)
    for area in bpy.data.screens['Image Viewer'].areas :
        if area.type == 'IMAGE_EDITOR' :
                area.spaces.active.image = bpy.data.images[0]

#you can add elif/switch for multi-extention handling

in your startup blend file you can create a screen layout and call it Image Viewer that is simply one UV image area

Now when you double click an image it will be handled by the batch script which will call blender that will run the python script responsible for importing ( or just opening ) the file in blender