I swear that I'm not going there place again, unless they pay me. But twenty years-and-a-month ago (roughly), I reconnected with a friend.  A good friend.  An epic, life changing friend.  My Epic EX Thing.  I just popped up out of the water like a dolphin, rubbed pool out of my eyes, and there he was.  Wow.

This is the sort of friend that turns you into the person that talks in paragraphs when one sentence really would have sufficed.   Because you're trying to soft pedal what you really mean so you don't look like a psychopath.  Or someone who is squinky on your ex-whatever.  Or whatever.  Social conventions suck.

I always knew what was going to happen, from the beginning.  He was always very distracted and looking for something better - a better situation or social group or whatever.  We'd sit in Kerby Lane for example (back when all the waitstaff was polite and that was a job requirement - and the nachos didn't look like a Jenga board and the queso didn't run off your chip and onto your shirt) ... we'd sit and then he'd scan the resturant for fame and fortune and Classmates and Spaces and Missed Connections.  This was before these things were even invented.

We would ponder things together.  The kind of things that don't matter but that do matter so very, very much.  Would my car make the Kessel Run in less than 12 parsecs?  How far away was the music building from the Tavern?  Analogous to the Kessel Run?  Which one of us was which - was he Stimpy and me Ren?  Which member of the Lennon/McCartney songwriting team were we the most like (that one was totally easy!).   Why are the lyrics to Paradise City so lame and yet they are so very important (actually, I may have talked about that one with my marine-brother)?  But it was stuff like that.  At the end though, as your heart is breaking and you review the relationship in your mind - you understand that you were kind of sitting there trying to get someone who thought they were much cooler than you ... to hang with you.  Only they were not cooler than you ... maybe not even as cool as you - sadly.

My sad feeding of the situation only gave it more power though, and I did not make myself very attractive to him, his people, or other people.  So really - this all ended up great.  It doesn't feel great ... but it's better for me.

I'm going to totally turn over a new leaf today.  I know that I always say that.  But I have to start somewhere.  And I have to be honest about it.  And I have to do it.

I canceled a rehearsal today.  I said that I was sick.  What I really did was get to that point.  Which made me too sick in my head to understand what to do about The Gear Problem.  Which is always when I start panicking.  Then I turn on my computer.  Which is never a good idea.  Then I start getting nostalgic.

Holy crap! I think.  He could totally help me do this!  I can get this under control! I don't even really have anything specific to do ... just the constant realization that time is tick-tick-ticking away and if I don't get it together I'm going to be a sixty old woman and it will all have just SHOT BY.

This is what happens when you have to be a self-motivator.  You have to learn to explain your nebulous plans ... uh ... less nebulously - and you have to get your dumb-ass back on track.  You have to pretend that your embarrassing life that you COMPLETELY bought into and structured much of your reality around didn't completely fall apart.  And you have to do the lion's (ha, ha) share of your mourning in secret; because you should have dealt with this MANY, MANY years ago.  But seeing as you are such a forgiving person and all - you are still hanging on, nice and peachy or whatever.

You = me by the way, in this little scenario.  This is what happens when I am trying to distance me from ... uh ... me.

Mourning about stuff I can't control is distracting me from my work - which is distracting me from the fact that when I'm on a computer I get frustrated because I am aimless and directionless.  I used to have my ass sewn together in a neat little list - compartmentalized into neat little boxes and it was all under control.

Control is everything PRIORITIZED.  And me not freaking out.  Control is me understanding the advice I am given from totally cool people that come over during the husband's Formula One extravaganza on Sunday night.  I totally put up with the high pitched buzzing noise because there was breakfast - and my boss/friend most awesomely helped me get out of half my shift at the El Job by interfacing with Jay (I am a fan of boss/friend right now completely-sorta).  Jay worked half the shift and is basically dealing with Cigar Girl because even though I don't maintain blogs - I am a professional blog creator and then leaver-alone-er.  It's ridiculous.  After this I am going to go to the OTHER blog and make some other goals ... maybe goals like ...

1.  Finish a freaking project.

This is what happens when you are In Mourning.  And I'm in mourning for so many things.  Many stupid things that lead up to more significant things that lead up to legitimate things that lead up to huge things that are subtantial but lame, already.  Leading up to the big doozy of a mourn that will last forever and ever amen.

That I don't talk about because you're either in the real mourning club or you're not.  And there's no way to talk about that because there's no way to describe it.  And I think I use other drama in my life to avoid stuff I really need to get to.  That distracts me from my work, ultimately.

If you get to the deep seated issues that you are trying to avoid ... it will make you a more productive person.  For the good reasons.

I've been putting a lot of energy into understanding homological algebra recently (following Weibel's book). And if there's one thing you do all the time in homological algebra, it's resolve things (a resolution of a module $latex A$ by X objects, where X is some adjective, is an exact sequence $latex \cdots\to B_1\to B_0\to A\to0$ or $latex 0\to A\to B_0\to B_1\to\cdots$ with each $latex B_i$ an X object). Resolutions help you to compute derived functors (e.g. the cohomology of something), which is a common goal. So I want to talk about how you can compute the derived functors $latex \text{Ext}^i_R(A,B)$ by resolving either $latex A$ or $latex B$, and why we should care.

This may or not really count as part of the "Shoulda Series" (1), since I'm pretty sure someone did tell me this at some point. But either way, I had to re-discover it for myself "in practice" before I "got it."

Throughout, let $latex R$ be a ring with unit (not necessarily commutative, but you can take it to be if you want) and let $latex A,B,C,\ldots$ and similar symbols be $latex R$-modules. We will use $latex P,Q,\ldots$ (resp., $latex I,J,\ldots$) for projective (resp., injective) $latex R$-modules. (Take all modules to be, say, right.) The first thing to recall is that for fixed $latex A$ and $latex B$, the functors $latex -\otimes_RB$ and $latex A\otimes_R-$ are right exact, while the functors $latex \text{Hom}_R(A,-)$ and $latex \text{Hom}_R(-,B)$ are left exact. The first three are functors $latex R\text{-mod}\to R\text{-mod}$, but the fourth is a functor $latex (R\text{-mod})^{\text{op}}\to R\text{-mod}$; this important point will become central in just a bit, so make sure you understand why! (Basically, a contravariant functor $latex F:\mathcal{C}\to\mathcal{D}$ is the same as a covariant functor $latex F:\mathcal{C}^{\text{op}}\to\mathcal{D}$. By $latex \mathcal{C}^{\text{op}}$, the opposite cateogry of $latex \mathcal{C}$, we simply mean the category obtained from $latex \mathcal{C}$ by keeping the same objects and reversing all the arrows.)

We may now define the $latex \text{Ext}$ and $latex \text{Tor}$ functors:

Definition: Define:
1. $latex \text{Tor}^R_*(A,-)$ to be the left derived functors of $latex A\otimes_R-$,
2. $latex \text{Tor}^R_*(-,B)$ to be the left derived functors of $latex -\otimes_RB$,
3. $latex \text{Ext}_R^*(A,-)$ to be the right derived functors of $latex \text{Hom}_R(A,-)$, and
4. $latex \text{Ext}_R^*(-,B)$ to be the right derived functors of $latex \text{Hom}_R(-,B)$.

The good news is:

Theorem: There are natural isomorphisms $latex \text{Tor}^R_*(A,-)(B)\cong\text{Tor}^R_*(-,B)(A)$ and $latex \text{Ext}_R^*(A,-)(B)\cong\text{Ext}_R^*(-,B)(A)$.

We denote the common values $latex \text{Tor}^R_*(A,B)$ and $latex \text{Ext}_R^*(A,B)$. The basic idea of the proof of the $latex \text{Tor}$ half of this theorem is to take projective resolutions $latex P_*$ of $latex A$ and $latex Q_*$ of $latex B$, take the tensor product bicomplex formed by these two resolutions, and then show that a certain chain complex is acyclic. (This chain complex is closely related to $latex \text{Tot}^{\oplus}(P_*\otimes Q_*)$, the total direct sum complex associated to the bicomplex $latex P_*\otimes Q_*$.) One then shows that $latex H_*(\text{Tot}^{\oplus}(P_*\otimes Q_*))$ is naturally isomorphic to each of the two derived functors. For $latex \text{Ext}$ the proof is similar, using injective resolutions, $latex \text{Hom}(I_*,J_*)$, and $latex \text{Tot}^\times$ instead. See Weibel, section 2.7 for the details.

In many situations, our goal is to compute (or at least gain knowledge about) $latex \text{Tor}$ and $latex \text{Ext}$. Recall that to compute left derived functors we resolve by projective objects, and to compute right derived functors we resolve by injective objects. Projective objects in the category $latex R\text{-mod}$ are great: a module $latex A$ is projective if and only if it is a direct summand of a free module. In particular, all free modules are projective. In practice, one can often use finite-rank free resolutions, which are comparatively easy to compute with (and can lead to finiteness results on the derived functors, automatically). One great example of this is the bar resolution (this is the chain complex described here), whose existence immediately tells you that the group homology $latex H_*(G;A)$ of a finite group $latex G$ has finite rank whenever the representation $latex A$ does.

But injective objects are not as nice to work with. The only decent general fact I am aware of is the following.

Baer's Criterion: Let $latex A$ be an $latex R$-module. Then $latex A$ is injective if and only if for every ideal $latex I$ of $latex R$ and every module homomorphism $latex f:I\to A$, there is a homomorphism $latex F:R\to A$ extending $latex f$.

This isn't bad, but it isn't nearly as helpful as in the projective case. And in fact, most injective modules turn out to be huge and/or nasty in some sense. So it appears that in general, $latex \text{Ext}$ will be harder to compute than $latex \text{Tor}$. This is a real shame, since $latex \text{Ext}$ usually has more interesting structure! (Think of $latex Ext$ as cohomology, where there is usually an interesting product, e.g., cup product on the singular cohomology of topological spaces.)

But all is not lost: Remember that the functor $latex \text{Hom}_R(-,B)$ is contravariant; equivalently, it is a (covariant) functor $latex (R\text{-mod})^{\text{op}}\to R\text{-mod}$. Since the universal property defining projective objects is dual to the universal property defining injective objects, it follows that the injectives of $latex (R\text{-mod})^{\text{op}}$ are precisely the projectives of $latex R\text{-mod}$! So when computing $latex \text{Ext}_R^*(A,B)$, we can either resolve $latex B$ by injective $latex R$-modules (usually messy and/or difficult) or resolve $latex A$ by projective $latex R$-modules (usually much nicer). For instance, the bar resolution mentioned earlier, which is a resolution of the trivial $latex \mathbb{Z}G$-module $latex \mathbb{Z}$ by free $latex \mathbb{Z}G$-modules for a group $latex G$, can be used to compute group cohomology, i.e., the groups $latex \text{Ext}_{\mathbb{Z}G}^*(A,\mathbb{Z})$. Hence as long as we are content to always resolve the first variable, $latex \text{Ext}_R^*(A,B)$ is just as easy to compute in general as $latex \text{Tor}^R_*(A,B)$.

Finally, I want to discuss something which puzzles me. The tensor product functor is left adjoint to the $latex \text{Hom}$ functor; that is, we an isomorphism
$latex \text{Hom}_S(A\otimes_RB,C)\cong\text{Hom}_R(A,\text{Hom}_S(B,C)),$
valid whenever $latex A$ is a right $latex R$-module, $latex B$ is an $latex R-S$-bimodule, and $latex C$ is a right $latex S$-module; this isomorphism is natural in all three modules. And one can show that this adjunction holds for the corresponding derived functors as well. So there is a very fundamental symmetry between the bifunctors $latex \otimes_R:\text{mod-R}\times R\text{-mod}\to\mathbb{Z}$ and $latex \text{Hom}_S:(\text{mod-}S)^{\text{op}}\times\text{mod-}S\to\text{mod-R}$. Simplifying to the case where $latex R=S$ is commutative, we have
$latex \otimes_R:R\text{-mod}\times R\text{-mod}\to R\text{-mod}$
$latex \text{Hom}_R:(R\text{-mod})^{\text{op}}\times R\text{-mod}\to R\text{-mod}.$

In this most important of adjunctions, why is there an opposite-category variable in one bifunctor but not in the other? Life would seem to make more sense if each of the two had one ordinary- and one opposite-category variable. I suspect that this may have to do with the fact that things are not as symmetric as they seem: even if $latex R$ is commutative so that left and right are equivalent, we are still talking about algebras (rings) and modules, while dually we could also talk about coalgebras and comodules. See the questions below, and enlighten me, please.

Questions

Here are a few questions which are bothering me, mostly related to the above. Comments, suggestions, examples, problems, etc. are more than welcome!

1. Philosphically/fuzzily/whateverly, why is there this weird asymmetry between $latex \otimes$/$latex \text{Tor}$ and $latex \text{Hom}$/$latex \text{Ext}$? Maybe the only answer is that "there happens to be an interesting adjunction of bifunctors where one side is covariant-covariant and the other side is contravariant-covariant." But this is really unsatisfying.

2. Is the answer to question 1 related to the fact that we are talking about algebras and modules, rather than coalgebras and comodules? If this is the case, then what do these bifunctors and adjunctions look like in the case of bialgebras?

3. Cohomology/$latex \text{Ext}$ has an interesting product structure. Does homology/$latex \text{Tor}$ have a coproduct structure? If so, when is it interesting?

4. Less related, but recently bothering me: Does anyone know of an example of a non-commutative ring which is Morita equivalent to its opposite?

[Background for 4: We say rings $latex R$ and $latex S$ are Morita equivalent if the categories are $latex R\text{-mod}$ and $latex S\text{-mod}$ of left modules are isomorphic. So in this case, I am asking for a ring $latex R$ whose left and right modules agree in some reasonable natural way, but which is not commutative.]

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Minix filesystem

1) The earliest versions of Linux used the Minix filesystem, which was developed by Professor Andrew S. Tanenbaum for use in his MINIX operating system, a small clone of UNIX that was intended only for computer science education purposes.

2) Although mostly free of bugs, it suffered from a small maximum partition size of 64 megabytes and a file name length limit of 14 characters.

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The extended file system, also called Ext

1) Was released in April 1992 and was included in the Linux kernel (i.e, core of the operating system) version 0.96c.

2) It overcame the main Minix limitations by allowing a huge increase in maximum partition size to two gigabytes and file names of up to 255 characters

3) However, ext still had problems: in particular, it lacked support for separate access for each user and group, and it also lacked timestamps for modifications to inodes and to data. An inode is a data structure on a filesystem on Unix-like operating systems that stores all of a file's metadata except its name.

4) Another problem was that the linked lists data structure ext used to track free blocks and inodes gradually became unsorted as the filesystem was used, thus causing the filesystem to become fragmented (i.e., parts of files widely dispersed rather than in contiguous blocks).

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Ext2 filesystems

1) Ext2 was initially designed by Rémy Card, a French software developer, based on ext but incorporating many ideas from the Berkeley Fast File System and with extensibility in mind.

2) Ext2 features (1) improved algorithms that greatly increase its speed, (2) additional timestamps (such as date of last access and date of last inode modification), (3) the ability to track the state of the filesystem and (4) support for a maximum file size of 4TB (one terabyte equals 1024 gigabytes).

3) It maintains a special field in the superblock that indicates the status of the filesystem as either clean or dirty; the latter will trigger a utility to scan the filesystem for errors. As a result of these improvements, ext2 has completely superseded ext.

4) Ext2 is designed so that data is held in blocks of equal size on the HDD or other storage medium, although blocks can be different sizes on different partitions, different HDDs, etc. The size is set when the filesystem is created by the mke2fs program. The disadvantage of this approach is that an average of half of the block size is wasted for each file. For example, with a a block size of 1024 bytes, each 1025 byte file would require two blocks.

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Ext3 filesystems

1) Ext3 has been integrated into the Linux kernel since version 2.4.16 and has become the default filesystem on Red Hat and some other distributions. It is basically an extension of ext2 to which a journaling capability has been added, and it provides the same high degree of reliability because of the exhaustively field-proven nature of its underlying ext2.

2) Also featured is the ability for ext2 partitions to be converted to ext3 and vice-versa without any need for backing up the data and repartitioning. If necessary, an ext3 partition can even be mounted by an older kernel that has no ext3 support; this is because it would be seen as just another normal ext2 partition and the journal would be ignored.

The ext3 file system adds, over its predecessor:

• A Journaling file system
• Online file system growth
• htree indexing for larger directories (specialized version of a B-tree — not to be confused with H tree)

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ReiserFS

1) ReiserFS, developed by Hans Reiser and others, was actually the first journaling filesystem added to the Linux kernel. As was the case with ext2, it was designed from the ground up for use in Linux.

2) However, unlike ext3, it was also designed from the ground up as a journaling filesystem rather than as an add-on to an existing filesystem, and thus it is widely considered to be the most advanced of the native Linux journaling filesystems.

3) Features include high speed, excellent stability and the ability to pack small files into less disk space than is possible with many other filesystems.

4) A new version of ReiserFS, designated Reiser4, was scheduled for release in the first half of 2004. It is a complete rewrite from version 3 and is said to result in major improvements in performance, including higher speeds, the ability to accommodate more CPUs, built-in encryption and ease of customization.

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JFS

1) JFS was originally developed by IBM in the mid-1990s for its AIX Unix operating system, and it was later ported to the company's OS/2 operating system. IBM subsequently changed the licensing of the OS/2 implementation to open source, which led to its support on Linux.

2) JFS is currently used primarily on IBM enterprise servers, and it is also a good choice for systems that multiboot Linux and OS/2.

3) JFS provides fast file system restart in the event of a system crash. Using database journaling techniques, JFS can restore a file system to a consistent state in a matter of seconds or minutes, versus hours or days with non-journaled file systems.

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XFS

1) XFS was developed in the mid-1990s by Silicon Graphics (SGI) for its 64 bit IRIX Unix servers. These servers were designed with advanced graphics processing in mind, and they feature the ability to accommodate huge files sizes.

2) The company likewise converted XFS to open source, after which it was also adopted by Linux. Because it is a 64-bit filesystem, XFS features size limitations in the millions of terabytes (in contrast to the still generous 4TB limit of ext2).

The XFS filesystem provides the following major features:

• Quick Recovery The XFS journaling technology allows it to restart very quickly after an unexpected interruption, regardless of the number of files it is managing. Traditional filesystems must do special filesystem checks after an interruption, which can take many hours to complete. The XFS journaling avoids these lengthy filesystem checks.
• Fast TransactionsThe XFS filesystem provides the advantages of journaling while minimizing the performance impact of journaling on read and write data transactions. Its journaling structures and algorithms are tuned to log the transactions rapidly.

  XFS uses efficient tree structures for fast searches and rapid space allocation. XFS continues to deliver rapid response times, even for directories with tens of thousands of entries.

• Massive ScalabilityXFS is a full 64-bit filesystem, and thus is capable of handling filesystems as large as a million terabytes.
• Efficient AllocationsXFS implements extremely sophisticated space management techniques. Efficiency in space management has been achieved through the use of variable sized extents, rather than the simple single-block-at-a-time mechanism of many other filesystems. XFS was the first filesystem to implement delayed space allocation for buffered writes, supports direct I/O, provides an optional realtime allocator, and is able to align allocations based on the geometry of the underlying storage device. The XFS allocator performs admirably in the presence of multiple parallel writers, and is renowned for its resistance to space fragmentation under such conditions.
• Excellent BandwidthXFS is capable of delivering very close to the raw I/O performance that the underlying hardware can provide. XFS has proven scalability on SGI Altix systems of multiple gigabytes-per-second on multiple terabyte filesystems.

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Comparison

Developer can place all external jars required by the Groovy script, in this ext folder (generally the location is  %SOAP_UI_HOME%\bin\ext).  Logic is all the jars in ext folder are set to classpath automatically on SOAP UI start-up; so one need not explicitly set the jar locations to CLASSPATH variable in \bin\soapui.bat file.

For example JDBC drivers, custom libraries, etc.. deserve a place in this folder.

(Please feel free to get back if u have any trouble...as I'm just a mail away...leave a comment otherwise)

The following are a list of the file attachments that are restricted by default
.ade            Microsoft Access project extension
.adp            Microsoft Access project
.asx            Windows Media Audio / Video
.bas            Microsoft Visual Basic class module
.bat            Batch file
.chm           Compiled HTML Help file
.cmd           Microsoft Windows NT Command script
.com           Microsoft MS-DOS program
.cpl            Control Panel extension
.crt            Security certificate
.exe            Program
.hlp            Help file
.hta            HTML program
.inf            Setup Information
.ins            Internet Naming Service
.isp            Internet Communication settings
.js             JScript file
.jse            Jscript Encoded Script file
.lnk            Shortcut
.mdb            Microsoft Access program
.mde            Microsoft Access MDE database
.msc            Microsoft Common Console document
.msi            Microsoft Windows Installer package
.msp            Microsoft Windows Installer patch
.mst            Microsoft Windows Installer transform; Microsoft Visual Test source file
.pcd            Photo CD image; Microsoft Visual compiled script
.pif            Shortcut to MS-DOS program
.prf            Microsoft Outlook profile settings
.reg            Registration entries
.scf            Windows Explorer command
.scr            Screen saver
.sct            Windows Script Component
.shb            Shell Scrap object
.shs            Shell Scrap object
.url            Internet shortcut
.vbs           Visual Basic Script

Available is ACS's new V series style Escalade Hood. The hood is a RTM molded product manufactured using ACS's OEM proven manufacturing process. Each panel is robotically trimmed and bonded to insure an easy installation on the vehicle.

Inspired by the XLR-V the hood has a center cowl in addition to two functional heat extractors. Fully functional extracting hot air from the engine compartment while directing rain water to the front of the hood away from critical engine components. Heat extractor openings are dressed with CNC billet aluminium grills. Designed to match the Escalade fender grills the grills are machined from a solid block of aluminium and triple chrome plated for a great look. This hood will surely set your Escalade apart from the croud.

Hood was designed following ACS's OEM experience with coated reinforced latch and adjustable rear hinges to properly fit the hood on your Escalade. Each hood is prepped and primed.

Hood will fit all 2007, 2008 Cadillac Escalade, ESV and EXT

Our whole group (which included my girlfriend and myself, my best friend Patrick and his new Costa Rican girlfriend whom we had just met) was fully aware of the difficulties involved in attempting to make the trek from the Pacific to the Atlantic in one drive. Thus, we decided it would be nice to treat ourselves to some luxurious dining the day before the big journey began. What we did not expect from this meal was to encounter one of those rare and precious moments in a lifetime, where everything in your life seems truly perfect. We ate the most magnificent seafood imaginable as we sat by the beautiful beach under the night’s sky and listened to the waves come crashing into the shore in a wonderful cadence, creating a peaceful ambience for our evening together. What’s more is that some of the culinary delights we were enjoying were on the house as my good friend Patrick explained to the waiter that we represented a Costa Rican travel service provider… nothing like corporate patronage, Costa Rican style!

And now for my end of the proverbial bargain through a shameless plug for this place… if anyone is ever in Brazalito, a sleepy town on the coast just north of Tamarindo in between Flamingo Beach and Tamarindo, you must visit El Camaron Dorado. Be prepared for the prices. They are certainly not typically Costa Rican. But I can state with absolute certainty that it is well worth the added expense. The quality of seafood served, its presentation, the charm of the waiters and the fact that you are literally sitting on the beach under the stars as you indulge in these delectable’s, more than makes up for the rather hefty bill that follows this unforgettable meal (Again, I need to re-iterate, the price is hefty by Costa Rican standards… this quality of meal would run anyone in a developed Western country in the hundreds of dollars per couple… we paid much less than half that price).

Needless to say, love and romance was definitely in the air for our two couples as we walked back along the beach to our resort and we went to bed with filled stomachs and anxious hearts for the day that was to come. The next morning, we got up as the sun rose (6 am for those that have not travelled to any equatorial countries), packed up our car and headed out for the trip back around *Arenal Lake (a must for anyone who appreciates beautiful sights… ok so a must for everyone*). Having been asked to take over driving duties after we stopped for breakfast was certainly interesting as I reminisced back to my last driving experience in Costa Rica just a over a year ago. I remembered with a chuckle being stuck in the middle of nowhere with an unleaded gasoline-filled, diesel SUV gas tank (please read: “What can happen…” for this interesting tidbit of a story). The post-breakfast part of our journey should have signalled events to come as the car would not start. We found ourselves pushing our car down the main road of a pueblito (Costa Rican for a small town that almost surely would not show up on any map) to get the engine to finally fire.

Obviously the vehicles owner, my best friend Patrick`s girlfriend, was slightly concerned. Strangely enough the car was only a few years old and although, as evidenced by my troubles at Costa Rican gas stations, I am by no means a mechanic, everything else seemed to be in perfect working order.

In case you have not guessed, I am foreboding our impending doom. Well, that perhaps is slightly melodramatic, but as I remember it, our doom as it were, began with another type of one of “life’s moments”: where time seems to stand still. As I drove through the arid desert-like climate of Guanacaste during the dry season and attempted to negotiate some of the highways pot holes at 80 km/h, I noticed something quite strange. Along one of the better roads I have driven in this country I watched as this flatter portion of Costa Rica actually provides for a slight mirage like effect. This became even more apparent as suddenly I noticed a massive Guanacaste tree branch (this normally beautiful tree is the province`s namesake). With a vehicle in the opposite left lane on-coming and the impending potential of yet another Costa Rican ditch incident my only other option to the right (again, see my “What can happen…” story), the aforementioned “moment” had arrived. I quickly decided an attempt to stop the vehicle before the enormous tree branch was my best choice. Slamming on the breaks and putting the clutch down I managed to bring the car to a stop within perhaps a foot of the large branch… phew! The strange part about stopping the car in this way is that the engine stalled (I could have swore I had the clutch all the way down). I could see the concern in Pat’s girlfriend’s eyes as I attempted to start the car again. Apparently Costa Rican manual transmissions need to be geared down even when slamming on the breaks (my unending and most sincere apologies again Georgia for my weak driving skills).

This whole episode put a little damper in our cross country adventure. Although we could eventually start the car again, the uncertainty of driving in the rural regions of a third world country with a vehicle that had stalled twice in the same day did not appeal to anyone, especially the vehicle’s owner… it was after all, her car (and no, they don’t have AAA or CAA here, I asked). So we found a small mechanics shop in the next town and stopped to see what we could find out about the vehicle’s conditions.

First let me clarify, by a mechanics shop I mean a couple of Costa Rican dudes working on some cars next to a little shack like shelter to protect from the elements while they did their work. Pat’s girlfriend Georgia engaged herself in a conversation with the mechanic about the troubles we had been having with the car and asked them what they thought. They said that it sounded like a problem with the battery as they inspected the engine. Patrick meanwhile got increasingly frustrated as he felt it had nothing to do with the battery, and that the recharging of the battery they were proposing would essentially be a waste of our time. I agreed as Patrick has a tendency to be right about these things. So I sat back, kept my mouth shut and feared the worst as we waited for the mechanics to do their work.

Patrick’s frustration would only grow as an American ex-pat turned rural Costa Rican local walked up to us and tried to explain to us what was wrong with our car. The American quickly transitioned the conversation to explaining his life’s story, which neither of us were interested in, nor in the mood for. As an aside on this topic: I have a couple of quick questions to all American`s (or “Gringos’’ as they are known here) who decide move to Costa Rica. Firstly let me clarify, as I am not talking to those that decide they will teach or live in Costa Rica for a while. Rather my query is only to those who actually decide to make their move permanent. My questions: Why do you, as an American living in Costa Rica, feel the necessity to boast to other Westerners (or Americans/Canadians rather) about the life in Costa Rica? Or how old you are and how young your Costa Rican wife is for that matter? Or even how well you were doing while in the US but that you just couldn’t live there anymore because of: a) George W. Bush, b) the society going to crap, c) the quality of life being worse in the US than in the more laid back Costa Rica. And lastly how every time you go back to the States you realize just how smart you are for having made that fateful decision one fine day upon discovering the wonder this country had to offer.

Now, I know many reading this may be thinking that the stereotypical Americans are normally quite arrogant in any case. I have heard this many times, even from close friends of mine, and I have never personally ascribed to that viewpoint. I am Canadian and I feel that Americans, with respect to personality or arrogance, are quite similar to Canadians. You can find some arrogant ones, just as you find arrogant Canadians occasionally. But generally speaking, I find Americans to be genuine and wonderful people whether you meet them in their hometown or travelling through Europe. And yet, for whatever reason, the ones I have met living in Costa Rica are very boastful and ignorant, thinking they have discovered some hidden treasure in Costa Rica that others just aren’t smart enough to understand. Believe me, we understand. That`s why most people who travel to Costa Rica go back a second and third time, and maybe more after that. So please don’t come to me in Costa Rica and tell me that in no uncertain terms I am an idiot if don’t decide to make the same amazing decision to move down that you did, thank you very much. I, like many others who have fallen in love with this beautiful land, have other things to consider when we decide to move a continent away from our families, spouses, loved ones, friends, not to mention jobs and other business interests. And no amount of talk about the 18 year old wife you hooked up with when you moved down here is going to entice me any more than the things I truly appreciate about this country, like its people, its natural beauty and the obligatory Church and Soccer pitch in every single charming and unique town can.

Back to the story now… As I sat there waiting for the car to have its battery charged (which Pat was right it didn’t need to be charged) and contemplated the American`s proposal to go to back his place for a fiesta, where his 18 year old wife and their daughters could prepare us a feast (hey, he was still a nice guy after all!), a scary thought suddenly came to mind: it was already the afternoon, we had another three quarters of the journey to go and no accommodations really booked on the Atlantic coast.

We thereby negotiated with the mechanic and advised him that we would not pay him for the battery charge as it didn’t help our cause, gave him a tip of 5000 Colones instead (about ten bucks) and decided we would tempt fate with the car. Sure enough we made it across the country in close to 12 hours instead of the usual 8. Although we ended up arriving at dusk, we were all in one piece, safe and sound and ready to start our quest to find a place to sleep. In case you’re wondering, the only problem with the vehicle at the end of this lengthy and fun filled trip was the headlights that decided they would not turn off.

Next time we rent!!

http://costa-rica-travel-and-vacations.com/

The next 3 are more recent releases:]

There is a little story behind the 3rd release. The boxed version was the US release to fit in with the other 2. The chrome Hummer packaged in a blister was a premium ordered by Daze shop in Japan.

Aunque en esta versión no estará activado por defecto, los administradores de Fedora 9 podrán utilizar fácilmente el soporte Ext 4 para su sistema de ficheros. Una de las principales características de esta versión es la defragmentación en linea que ofrece una mayor rendimiento y confiabilidad del sistema de ficheros.

Linux tiene soporte para diferentes sistemas de archivos, algunos son sistemas de archivos de redes especializados o son sistemas de archivos desarrollados para otros sistemas operativos. Una sorprendente cantidad de ellos pueden ser utilizados como sistema de archivos nativo en Linux: ext2, ext3, ReiserFS, XFS, y Journaled File System (JFS). De todas formas el desarrollo continua y nuevos sistemas de archivos están en el horizonte.

Quizás el más importante sistema de archivo en desarrollo actualmente sea el ext4, la cuarta versión del sistema de archivo extendido (extfs) desarrollado exclusivamente para Linux.Tal vez el próximo estándar para Linux en un futuro no tan distante.

La cuarta extensión del sistema de archivo (ext4fs) existe porque algunos desarrolladores querian incorporar nuevas y mejoradas características al ext3.

Ext4 ofrece grandes ventajas sobre ext3. Por ejemplo, soporte para sistemas de archivos de hasta 1024 PiB y archivos de esta 16 TiB (ext3 soporta hasta 36 TiB en sistemas de archivos y 2 TiB en archivos, aunque dependiendo de la arquitectura del sistema los limites podrían ser tan bajos como 2 TiB para el sistema de archivo y 6 GiB para los archivos). Los “extents” son una manera de mejorar la eficacia de los descriptores de archivos, reduciendo los tiempos de borrado en los archivos grandes, entre otras cosas. En ext3 puedes tener hasta 32.000 subdirectorios, en ext4 ese limite no existe. ext4 registrará el tiempo de los archivos en nanosegundos. En general ext4 esta desarrollado para obtener un mejor rendimiento y confiabilidad que ext3.

Si deseas conocer más sobre este nuevo sistema de archivo o de migrar/experimentar con el te recomiendo leer Migrating to ext4, una excelente guía que te permitirá activar el soporte para ext4, migrar de ext3 a ext4 y finalmente mantener un sistema de archivo con ext4.

Via | Lianlco

In its second innings, World Wide Web has introduced a newer approach to interact, organize & categorize information. With new Web 2.0 sites cropping up all over the place, the value of tools (& libraries) coming up to facilitate creativity and giving browser a bigger role to play in business interaction are talk of the town for the developers all around the world.

Apart from Ext JS library (http://extjs.com/), JackBuilder (JackBe), Flex (Adobe), GWT (Google), GI (Tibco) are other few Ajaxified GUI development tools that come to my mind, serving the similar cause. This article is first up in the series of Web 2.0 technologies that we will continue, and star of the show today is ext js.

There are already a few good articles available on ext js forum that talk about integrating Ext with DWR. Here's one that I would recommend: http://extjs.com/forum/showthread.php?t=5586. Taking this further, the scope of this article would be creating a Data Grid (using Ext) for CRUD operations. Refer Ext API docs at http://extjs.com/deploy/dev/docs/. The package you need to emphasize for this article is Ext.data.*

1. Ext Data Grid (Ext.grid.GridPanel) can be percieved as a Table where each row is a Record (Ext.data.Record). These records will be fetched from the server and cached using Ext.data.Store object.

2. Ext.data.DataProxy, an abstract class extended by Ext.data.DWRProxy (refer DWR article from the link mentioned above), is the proxy configured for Ext.data.Store object to fetch data objects from server.

3. Now this store object is totally agnostic to the format of the data returned by the Proxy. This allow developer provide their own configured implementation of Ext.data.DataReader to convert these data objects into records and make them available.

Lets start on how one can create a proxy to be used by GridPanel.

ds = new Ext.data.Store({
    proxy: new Ext.data.DWRProxy(., true),
    reader: new Ext.data.ListRangeReader({
        id: 'field1',
        totalProperty: 'totalSize'
        }, Ext.data.Record.create([{
                name: "field1",
                mapping: "field1",
                type: "int"
            }, {
                name: "field2",
                mapping: "field2",
                type: "string"
           }]
        )
    )
});

To instantiate Ext.data.Store, the config object passed to the constructor included two properties; proxy & reader.

• The property proxy is an instance of Ext.data.DWRProxy. As I said before, this being an extension of the DWR article I have already referenced, so my DWRProxy implementation remains same. Other subclasses of Ext.data.DataProxy (provided by ext js) are Ext.data.HttpProxy, Ext.data.MemoryProxy, Ext.data.ScriptTagProxy.
• The property reader is instantiated as Ext.data.ListRangeReader. The reader object is chosen according to the format of resultset that your dwr method returns. Other extensions of Ext.data.DataReader are Ext.data.JsonReader, Ext.data.XmlReader & Ext.data.ArrayReader.

Every Reader is different in a way the format used by the server to return the data objects alongwith the addon properties needed like, total number of records etc. The constructor for a DataReader needs two things. A config object and a Record definition. The config object includes:

• id to specify which field will be used as the identifier for each row.
• totalProperty to specify which field contains information about total number of records the server returns.

The other argument, Record object, is an array of objects which provides mapping of property elements in data object to those in a grid record.

To make it more clearer, the result for which a ListRangeReader is appropriate looks like this:

{
    data: [{
        "field1": 1001,
        "field2": "data1"
    },{
        "field1": 1010,
        "field2": "data2"
    }],
    totalSize: 2
}

For JsonReader, check out http://extjs.com/deploy/dev/docs/output/Ext.data.JsonReader.html

Thanks to Ext API docs, creating Grid comes easy. The instantiation is self-informative enough to get in one's head.

grid = new Ext.grid.GridPanel({
            el: "div_to_render",
            autoScroll: true,
            autoHeight: true,
            autoWidth: true,
            ds: ds,
            cm: new Ext.grid.ColumnModel([{
                header: 'Field1 Header',
                width: 250,
                sortable: true,
                dataIndex: 'field1'
            }, {
                header: 'Field2 Header',
                width: 250,
                sortable: true,
                dataIndex: 'field2'
            }]),
            sm: new Ext.grid.RowSelectionModel({
                singleSelect: true,
                listeners: {
                     rowselect: function(smObj, rowIndex, record) {
                         selRecordStore = record;
                    }
               }
            }),
            autoSizeColumns: true,
            trackMouseOver: true,

            tbar: [new Ext.Toolbar.Button({
                        text: 'Add',
                        handler: function(){
                        //Load New Form
                     }
            }), new Ext.Toolbar.Button({
                        text: 'Edit',
                        handler: function(){
                        //Load New Form
                        //Load Data

                        form.loadRecord(selRecordStore);
                  }
            }), new Ext.Toolbar.Button({
                        text: 'Delete',
                        handler: function(){
                        //Call for Delete for the record with this identifier
                        var id = selRecordStore["field1"]
                }
            })],

            bbar: new Ext.PagingToolbar({
                        pageSize: 2,
                        store: ds,
                        displayInfo: true,
                        displayMsg: 'Displaying Records {0} - {1} of {2}',
                        emptyMsg: "No Records to display",
                        items: ['-']
            })
});

Wondering, if I haven't deviated away from the scope of this write up, notice that I have configured a listener for the Grid Selection Model which stores the reference of the records mapped for the row selected. This record is used by Toolbar Button handler for the actions specified.

This concludes my say on using Ajax based Ext JS Data Grid which looks difficult to use, first time u look at it, but provide us various features to configure, like Paging, Toolbar etc.

Note: For this being an introductory article to startup, I have tried my best to stay focussed on my scope. Based on the reviews/responses, I can follow it up with a working example.

References:
1. Ext JS Forum
2. Ext JS API Documentation ]]> http://crazylion.wordpress.com/?p=451 Mon, 24 Mar 2008 13:09:46 +0000 CrazyLion http://crazylion.pt-br.wordpress.com/2008/03/24/%e5%88%9d%e5%98%97ext-20/ 最近要幫學長做個網頁端的呈現介面。 於是決定試試看 ext 。 沒想到......真的非常複雜....

用過之後我是覺得 ext 2.0 適合整個網站的規模，像我這種一兩頁的就不是很適合。尤其在改樣式方面...挺吃力的阿@@

所以可能還是會回到jquery or GWT 吧...