Dec 28

Prolog Language References

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I’m currently reviewing an existing system written in vb6 that management at the company I work for has finally decided to get behind porting it. Their plan is to port it to Visual Studio (VB.net) as that is what they are comfortable with. I understand this desire, but I’m also hesitant to jump right in and do so because they are also looking for “better ways to do things” during the transition. This particular system is very “rules driven” and we have a massive amount of code dedicated to supporting these rules. In my opinion this is just screaming for Prolog to be a part of the solution, and since I have some say in the matter I’ll be as neck deep in prolog over the next couple of months. I’ll be trying to get a proof of concept in place before the conversion gets underway so I can prove its value. Either that, or I might just prove that it won’t do the job I want it to and I will be able to dive into the rewrite as previously planned without hesitation or hinderance.

While I can’t tell you what the project is I can tell you that in just one of my fact databases I expect to have well over 1/2 million facts. The facts are relatively static so that’s good. The facts will be queried upon often over 1million times per day and it should be able to handle that without breaking a sweat as this is only about 5% of the total volume we expect to see.

So, that being said, I’m working on compiling a list of Prolog references (websites mainly) that will help me progress as quickly and painlessly as possible. If you have any suggestions for books I’d also love to hear them and will likely be adding them to the post or as seperate posts as I go.

So, here come my links on into topics:

http://boklm.eu/prolog/page_0.html

SWI-Prolog
A short Introduction to Prolog
A Short Tutorial On Prolog
Introduction to Prolog for Mathematicians
iProlog Programmer’s Manual
Prolog Tutorials
A Concise Introduction to Prolog

 

Dec 04

IF (by Rudyard Kipling)

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True in sports, business, and life in general:

IF you can keep your head when all about you
Are losing theirs and blaming it on you,
If you can trust yourself when all men doubt you,
But make allowance for their doubting too;
If you can wait and not be tired by waiting,
Or being lied about, don’t deal in lies,
Or being hated, don’t give way to hating,
And yet don’t look too good, nor talk too wise:

If you can dream – and not make dreams your master;
If you can think – and not make thoughts your aim;
If you can meet with Triumph and Disaster
And treat those two impostors just the same;
If you can bear to hear the truth you’ve spoken
Twisted by knaves to make a trap for fools,
Or watch the things you gave your life to, broken,
And stoop and build ’em up with worn-out tools:

If you can make one heap of all your winnings
And risk it on one turn of pitch-and-toss,
And lose, and start again at your beginnings
And never breathe a word about your loss;
If you can force your heart and nerve and sinew
To serve your turn long after they are gone,
And so hold on when there is nothing in you
Except the Will which says to them: ‘Hold on!’

If you can talk with crowds and keep your virtue,
‘ Or walk with Kings – nor lose the common touch,
if neither foes nor loving friends can hurt you,
If all men count with you, but none too much;
If you can fill the unforgiving minute
With sixty seconds’ worth of distance run,
Yours is the Earth and everything that’s in it,
And – which is more – you’ll be a Man, my son!

Oct 26

My iRobot Looj (gutter robot) experience

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I got my iRobot looj “gutter robot” yesterday. I’ve been really looking forward to getting one for a while now and finally got it ordered late last week. Not bad for a delivery time! I think I ordered it on Thursday and received it tuesday with free shipping.

Include in the box were two batteries, a charging device, the robot itself including the remote, a beltclip, and two augers. It came in a nice tool case (like you might get with a cordless drill or other cordless power tools) that will allow me to store it neatly out of the way when I’m not using it so I’m liking that too.

I’m writing this because I read various reviews and some were good while others were not so much. I wanted to write it while it was fresh in my head (I just used it about 2 hours ago) because I remember thinking while I was using it that “man, I didn’t realize…” so I figured I’d give a heads up to anyone else looking to spend their money.

First, I want to say that I think this will make cleaning my gutters much safer. I hate getting up and down off the ladder. The way my house was built leaves me with what amounts to second story gutters and I just hate climbing up and down over and over again to clean them. The other option I had was to climb up on the roof and just crawl along the entire roof line on my hands and knees scraping out the gutters by hand. This required me to be way to close the edge contantl and made me really nervous on the steeper graded parts of the roof (which
also happened to be over the highest part of the roof directly over my stone patio). With this looj I was able to find one place that I could climb up, place the looj, and then let it do its thing to clean pretty much the entire gutter area on the back of my house.

It worked pretty well. The gutters got clean enough. I can honestly say that if I was paying a person to clean my gutters. I would require them to have done a better job as there was still some debris left when all was said and done, but probably 95% of it was able to be cleared by the looj. Keep in mind this is a rookie “driver” and I was in a bit of a hurry as I had to get back to work so it might have done even better if I knew what to do, but it worked pretty well regardless.

You do have to pay attention while you use it. You can’t just set it and forget it. For example, I did encounter a couple of times where the looj rolled over. Basically the auger got stuck in some mess that it wasn’t able to break up and so the robot itself just started spinning. It was amusing in a way, but not so much in that I had to go rescue it. It seemed that several times it just quit responding for a few seconds, but then it when right back to working. I don’t know if it got to the edge of the range of the remote or what… in any case it did not make the device unusable, just a little quirky.

I did have one downspout for which the auger never was able to clear out the opening. I had to climb up and clear that one downspout myself. This is still significantly less work than I normally have to do.

This first use was in gutters full of dry leaves, some acorns, and very few pine needles. It hadn’t rained for a couple of weeks so the leaves weren’t wet and the gutters weren’t wet. It took a few passes to get everything out. I plan to use it again soon after a rain (it will rain tonight and I don’t have time to do the front before the rain will be here) so I’ll be able to see which way works best. The second test will includes lots of pine needles so we’ll see how it actually handles them!

I do not think that this device will make my gutter cleaning faster. Working the looj back and forth to get it through heavier jams may actually make it take longer, but I do think it will make it much safer and require less physical exhertion on my behalf.

Cleaning the device for storage was super easy. I just turned on hose and rinsed the looj off. It was pretty “cruddy”, but nothing major and cleaned up quickly and easily.

If they make another model then I would recommend making it a little heavier (maybe 50%) and make the tread motors a little tougher.

I plan to do another review once I get a chance to try this on my gutter that has a pineneedle problem just to report on how that goes. For now though, I’m pretty darn satisfied with the value I received for the money I spent.

Oct 02

iPhone and iPad naming conventions, icon descriptions, and icon sizes

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The below table is a description of iphone icons and ipad icons, what they’re sizes and should be, and what their standardized names are. This information is all over, but the a thorough and yet concise version (and what i based the below on) can be found here.

Name Size (pixels) Platform
Icon.png 57 x 57 Universial application icon
Icon-settings.png 29 x 29 Universial application icon for settings area. Alternative name: Icon-Small.png
Icon~ipad.png 72 x 72 iPad application icon. Alternative name: Icon-72.png Add some smaller (iPad doc: 64×64, other optional 32×32, 24×24, 16×16) custom icons to your project. See comments.
Icon-spot~ipad.png 50 x 50 iPad icon for spotlight search. Alternative name: Icon-Small-50.png iPhone OS trims 1 pixel from each side and adds a drop shadow. The actual size is 48×48 pixels.
iTunesArtwork.png 512 x 512 Universial application icon for iTunes App Store. Uploaded separately to iTunes. It’s included in the app bundle too, file name: iTunesArtwork. In an iPad application iPhone OS uses this image to generate the large (320×320) document icon if it is not supplied otherwise.
Default.png 320 (w) x 480 (h) iPhone/iPod 2, 3 portrait launch image
Default@2x.png 640 (w) x 960 (h) iPhone 4 hi-res portrait launch image
Default~ipad.png 768 (w) x 1004 (h) iPad. Specifies the default portrait launch image. This image is used if a more specific image is not available. Use full size template (768×1024) to design this launch image. The 20 pixels height statusbar is on by default and occupies the top of the screen, aka the 1004 rows vs. 1024.
Optional icons and images:
Icon@2x.png 114 x 114 iPhone 4 hi-res application icon
Icon-settings@2x.png 58 x 58 iPhone 4 hi-res application icon for settings/search area
Icon-doc.png 22 (w) x 29 (h) Universial document icon
Icon-doc@2x.png 44 (w) x 58 (h) iPhone 4 hi-res document icon
Icon-doc~ipad.png 64 x 64 iPad document icon (small)
Icon-doc320~ipad.png 320 x 320 iPad document icon (large)
Background-xxx.png 320 (w) x 480 (h)
640 (w) x 960 (h)
768 (w) x 1024 (h)		 iPhone/iPod Touch 2, 3 background image,
iPhone 4 background image, full size
iPad background image, full size. For most projects the status bar is hidden, so use full screen size by default.
Default-PortraitUpsideDown~ipad.png 768 (w) x 1004 (h) iPad. Specifies an upside-down portrait version of the launch image. The height of this image should be 1004 pixels and the width should be 768. This file takes precedence over the Default-Portrait.png image file for this specific orientation.
Default-LandscapeLeft~ipad.png 1024 (w) x 748 (h) iPad. Specifies a left-oriented landscape version of the launch image. The height of this image should be 748 pixels and the width should be 1024. This file takes precedence over the Default-Landscape.png image file for this specific orientation.
Default-LandscapeRight~ipad.png 1024 (w) x 748 (h) iPad. Specifies a right-oriented landscape version of the launch image. The height of this image should be 748 pixels and the width should be 1024. This file takes precedence over the Default-Landscape.png image file for this specific orientation.
Default-Portrait~ipad.png 768 (w) x 1004 (h) iPad. Specifies the generic portrait version of the launch image. The height of this image should be 1004 pixels and the width should be 768. This image is used for right side-up portrait orientations and takes precedence over the Default~ipad.png image file. If a Default-PortraitUpsideDown.png image file is not specified, this file is also used for upside-down portrait orientations as well.
Default-Landscape~ipad.png 1024 (w) x 748 (h) iPad. Specifies the generic landscape version of the launch image. The height of this image should be 748 pixels and the width should be 1024. If a Default-LandscapeLet.png or Default-LandscapeRight.png image file is not specified, this image is used instead. This image takes precedence over the Default.png image file.
Sep 29

How to let your iphone or ipad apps check for network access – reachability

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I have recently been working on a new iOS app for the iPhone and I ran into a couple of issues. I don’t really have time to go over them all in this post, but I did want to document one of them because I hear it can be a big deal as far as getting your app approved by Apple. The issue is that of making sure you handle things gracefully if the user’s phone is unable to connect to the internet and they try to do something that does require a connection.

The way I decided to handle it was to use the reachability collection provided by apple. I downloaded the reachability sample from Apple and then copied and imported the 4 files from the “classes” directory into my project.

Then I added the “SystemConfiguration.framework” to my project.

Now I have all of the prereqs for my solution. The next thing I did was I created a NetworkReachabilityTest class with NSObject as its base class. I added a single method called “isNetworkReachableWithAlert” that returned a bool and included one parameter. The parameter specified whether it should automatically pop up an alert box in case of a lack of network connectivity.

I chose to do it this way (as a dumb small class) so I didn’t have to copy the code for this method into every page. Plus it gives me the flexibility to easily reuse it in future projects. So now, before I do something that requires network connectivity I instantiate an instance of this class, I do the check, and if the connection is there I do the work. If the connection is not there I can bail out instead.

Here’s the code (some of this code was included in the example and some was found here around post 29 or 30:

-(BOOL) isNetworkReachableWithAlert:(BOOL)bshowalert

{

Reachability *r = [Reachability reachabilityWithHostName:@”www.signandtrade.com”];

NetworkStatus internetStatus = [r currentReachabilityStatus];

if ((internetStatus != ReachableViaWiFi) && (internetStatus != ReachableViaWWAN))

{

if (bshowalert)

{

UIAlertView *myAlert = [[UIAlertView alloc] initWithTitle:@”No Internet Connection” message:@”An internet connection via WiFi or cellular network is required for this portion of the app to work.” delegate:self cancelButtonTitle:@”Ok”   otherButtonTitles:nil];

[myAlert show];

[myAlert release];

}

return NO;

}

return YES;

}

That’s in the implementation file  of my simple class and it is basically the only thing there! And it does everything we need.

And here it is in use:

NetworkReachabilityTest *nrt = [[NetworkReachabilityTest alloc] init];

if ([nrt isNetworkReachableWithAlert:YES])

{

// logic that requires or includes web activity here

}

[nrt release];

Hope that helps. Hope it makes sense. Better ideas or improvements on it are welcome, I just wanted to give someone a simple example of something that I know works  along with the steps I took to make it work.

Sep 25

Printing from within a WinXP Virtualbox client with a Mac OSx host

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I have an Mac OSx machine on which I have virtualbox installed. My most often used virtual client machine runs Windows XP. Almost everything works great, but I was having a lot of issues getting printing to work. I finally got everything figured out though and figured I’d write it up real quick. So here’s what I did.

The first thing I would recommend doing if you have a setup like mine is to find the driver for the printer that you need to print to. Why? Because the apple software that I point you to below will install a driver by default that technically works, but it makes everything you print come out super small. [Actually, as I’m writing this is occurs to me that it may be doing this when I print because Apple assumes an HP printer in their tool, but mine is an Epson.  So maybe the default installed by the program provided by Apple will work “out of the box” for an HP printer… But I would still go ahead and get the correct driver for your printer first.]

Then once you have the driver on the client do the following (found this at virtualbox.org forum and quoted from here):

1) Shutdown the VirtualBox machine
2) Under Mac OS X

  1. System Preferences, Print & Fax, Check “Share this printer on the network”
  2. System Preferences, Sharing, Check “Printer Sharing” and Check the printer

3) VirtualBox machine, Network:

  1. if only one adapter selected and it is attached as NAT [this is the default], then add Second adapter. Make it attached as Host-only Adapter and choose the name: vboxnet0 (see note B at the bottom if you can’t find this).
  2. if the adapter is attached as Bridged Adapter, then do nothing (you have a reason to be Bridged?)

4) Start up the Vbox machine – let it adjust to added Network Adapter
5) Download and install from Apple “Bonjour Print Services for Windows” http://support.apple.com/kb/DL999
6) start Bonjour Printer Wizard and follow the menus

Note A: That wizard will allow you to print from the client using the printer on the host MacOSx machine. But that wasn’t it for me because Apple defaulted to an HP driver which caused the pages to print all tiny on my Epson. It was an easy fix though. I just had to go back and run the brand specific printer driver install (or manually change the printer driver for the printer added by the apple wizard) so that it would use the brand specific driver instead of the Apple default.

Note B: I did a fresh vbox install to test this because some people weren’t seeing the vboxnet0 at this stage. I was able to reproduce the problem and fix it based on another reader’s suggestion. All I had to do to get it fixed was go to ‘VirtualBox’->’Preferences’->’Network’. It’s probably completely blank for you if you’re reading this note. What you want to do is just click the little green plus to add a new hostonly network and it’ll add ‘vboxnet0’. Now go back and finish the tutorial where you left off and you should be printing in no time. Hope that helps.

Note C: In the comments below you’ll see a couple of readers (Jeffrey Weber and Leigh Warren) that were only able to get things working by using Bridged instead of HostOnly (see step 3 above for where this matters). The “method” I defined in the main part of the post seems to work in most cases, but there is obviously some type of setup that requires bridged rather than host-only. I recommend that you try it the original way first and then double check everything if it doesn’t work. After that if the original way still doesn’t work you might try tweaking this setting going bridged instead. Keep in mind that if you’re already bridged and everything is working then, as the original write up says, do NOT add the host-only.

Aug 28

Some thoughts on Software Patents

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I have read a lot of what I consider to be fairly convincing arguments relating to software patents and whether the courts should “allow them” or “ban them”. Before I had the insight I’m going to share below I was definitely a fence hopper, but I think I have finally satisfied myself with an answer. It takes a wee bit of imagination and a willingness to be somewhat philosophical to get there, but I think the thought process will get you there.

 

If you’ve seen “The Matrix” you know that almost the entire movie involves real people living and acting in a virtual world. If you’ve seen “The Matrix Reloaded” you’ll remember a scene where a ship is returning to realworld city of Zion and they are getting ready to enter the gates to the city. The city is very mechanical and computers are utilized to control everything, but do the people of Zion who operate the computers sit behind a keyboard? No they don’t. Instead they “plug in” in the real world transferring they minds into the virtual world in which someone (presumably other humans) has programmed all of these controls. The controls cool thing about these controls is that not only can they be laid out like a keyboard, but they can also be like a lever. It’s their own virtual world so they can build it however they want. They just need to be presented with an environment that they can manipulate to get “the job” done.

 

Now imagine current earth humans being able to allow their mind to live or work inside of a virtual world. Everything in that virtual world is actually software! Nothing is physical though it could be designed to look it and feel it. It may be designed such that your physical actions (ie grabbing a lever and pulling / pushing it) causethe software to behave in different ways, but it’s still not actually physical. How you interact with that software simply causes some state change in the outside world, but what you are interacting with IS software. Yes, the changes you introduce by manipulating the controls made available to you will cause some other software to cause changes in the outside world which will in turn cause a change to the view of the world presented to the those in the virtual world (and in the physical world). But it’s still software making it all work. The tools are software. The connections are software. The actor could even be software.

 

Once these types of systems are possible, and especially once they are common place, there could be a rush of what, in the physical world of today, we would call innovative people coming up with new widgets that can be used inside of this virtual world. These innovations will almost surely come with a price that would be paid by the programmer. In that case there would be a need for protection under some type of law in order to encourage people to create, test, and perfect them. Do we have a system that provides this sort of protection today? Yes, we do, and it is the patent system. It would also be applicable to this sort of situation considering the new types of “tools” that people would “physically” interact with inside the virtual world. All manner of things are possible in the real world today that we just knew wasn’t possible before (until someone innovated a way to do it), and the same will be true in the virtual world. Ways of doing things never even thought of will be, given the right motivation, not only thought of but implemented and improved upon. Different ways of looking at problems will cause unique solutions to become apparent. The solutions would be “obvious” once pointed out, but would be nonobvious prior. Why would someone dedicate their time to looking for alternate solutions if the answer will net them no reward? History shows us that they won’t… not to the same degree anyway.

 

Q: What about a hammer vs a “virtual hammer”? Would you really allow a patent on a virtual hammer that does the same thing in software world that it does in the real world? That seems like everything would get repatented with the only difference being that it is “in software”.

 

A: This question stems from one of the common errors untrained people make when judging patent validity. You can’t just look at the title, or the summary. Think about it. A software hammer wouldn’t be the same thing as a hardware hammer would it? Software doesn’t have physical nails to drive. But maybe a software hammer can be made such that it easy automates the binding of two or more components using a single connective module. Something that used to take 10 virtual actions can be easily rolled  up into the action of hitting the objects with a hammer. The hammer basically just does all of those steps that “physically” had to be done before and elminates them through some ingenious “piece of code”. Testing this peice of code and finding just the right tweaks for it came with a cost of thousands of lost operations (cpu cycles), mangled data, and even memory leaks that had to be dealt with before it became stable to be used in the virtual world. Why would someone give up these precious resources if it would not gain them some advantage? Now that it is done it is a easily copyable solution so what’s to stop another from copying it and using it without having put their own butts on the line? Copyright doesn’t do the trick as code can be rewritten (hell, translate it to another language and you’ll have to modify it to do so). You’re still using the same algorithm, but it obviously not the same code. Yes it is and you shouldn’t be allowed to steal the code, change the language, and call it new.

 

It is my belief that as things become more virtualized and as virtual reality starts to become both more real and more immersive that we will see more need for patents on things in the virtual world. These things are no doubt software. But they are also no doubt in need of protection.

 

To be continued… or is this one step too far?

 

And if we know that software should be patentable in the case of said eventual world, then software should be patentable now due to the simple fact that the simulation argument leads there.

 

May 14

To lock down or not lock down

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A while back I did a post about making sure that you lock down your wifi so that people do not do nefarious things on your connection and get you into trouble. Well, apparently that was not the best “legal” suggestion. Apparently, if your wifi is open and someone does something wrong then, well, it could have been anyone that was using your IP. But if your wifi is closed and something is done wrong (beginning at your IP address) then you are viewed as that much more likely to be the target of an investigation. Afterall, who could have been using your IP? Your wifi was closed!

According to the Electronic Frontier Foundation (EFF), keeping your router OPEN may offer more legal protection than having it closed.

If you run an open wireless network, you may be able to receive significant legal protection from Section 230 of the CDA (against civil and state criminal liability for what others publish through the service) and Section 512 of the DMCA (against copyright claims based on what others use the service for). While these protections are not complete, EFF regularly engages in impact litigation to help ensure that these laws offer as strong protection to network operators as possible.

The fact is that wireless router security is often viewed as something you just set up and then leave alone and it works to keep the bad guys off your line. However, wireless security is relatively weak and much of it can be broken. It won’t be long before the bad guys have access to your locked router and start making trouble. When they do, it will look like YOU are the one making trouble. On the one hand, you hate to give the bad guys a free ride, but on the other hand you would hate to get punished for what they do if they stole your ride and did something inappropriate with it.

I continue to go back and forth on this one. I have gone months with my router open, and then some time with it closed. I usually have to close it due to too much bandwidth being used. My netflix will start lagging (don’t mess with my Sarah Conner Chronicles!) or whatever and I know that someone is getting a little happy with my bandwidth.

It makes me nervous both ways to be honest. I have several houses with teenagers that live around me, all with wireless reach. Do I want them going to sites or performing illegal activities over my router? Nope. Do I want them using up all my bandwidth? Nope. Do I want to be nice and allow for free access? Yes. Do I want to have someone crack my WEP, gain access to my router, and then do unruly things so that it appears it was me? No way! So what I do? What would you do?

My plan is to in general go open wireless. Sometimes I’ll close the open access if I have bandwidth hogging issues and then I’ll open it back up once I think they’ve gotten the point. If you come around and don’t find an open network currently available don’t be discouraged. I have likely gone into non-sharing mode for a short time in order to get the bandwidth hogs to move along and will reopen for public use soon enough. Really, this isn’t much of a change. I like to provide a needed service, and I understand the need for open wireless points. Now that I see there are even legal “goodies” to go along with having it open I feel even better about the way I’ve operated historically and will continue to lean towards open, available wireless.

Mar 29

Context Clues (why is there a lion on the radio?)

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Kids are so awesome… they’re just missing the filter that most of us have that keep us from asking silly questions. I mean, after all, maybe there are special situations where a lion might actually be on the radio!

The other day I was driving my 5 year old home from ballet class. We were chatting about class and when we were done I started my Dave Ramsey podcast up. For those of you who are unfamiliar with Dave Ramsey I’ll just tell you that he is someone who helps people become financially secure by providing them with a plan for paying off their debts and getting their finances / investing in order. He does a radio show, live events, has some books, and more I’m sure. I may have done him a great disservice with that super brief description, but, to be honest this post isn’t about him… it’s about my kiddo and her use of context clues.

She hears Dave talking on the radio and says “who is that”.

Daughter (5 yrs): Who is that?

Me: On the radio? That’s Dave Ramsey.

Daughter: Who? Is that a man or a woman?

Me: Well, the caller was a woman. But the person talking now is Dave… and he’s a man.

Dave just finished with the previous caller and now a new caller is getting started.

Radio: … Hey, Dave. Thanks for taking my call. I was just wondering….

Daughter: What!? Why is there… Is there a lion on the radio?

Me: Huh? What did you say?

Daughter: Is there a lion on the radio?

Me: A lion? I thought that is what you said.

Now, at this point I’m not sure what is going on in her head, but I’ve learned that this one doesn’t generally ask goofy questions for no reason. There is usually some thought that actually gets her here. So I try to figure out how we got here.

Me: So…. why would you think there was a lion on the radio.

Daughter: He has a paw. (very nonchalantly)

Me: Ummm… I don’t understand. He has a paw?

Daughter: Yeah, he said “Hey, Dave. Thanks for shaking my paw”.

Me: Ahhh… I think you misheard him, kiddo. He said, “Thanks for TAKING MY CALL”.

This idea made much more sense to hear than the idea that there was a lion on the radio, but her little mind made sense of what it thought it had been presented with and didn’t skip a beat. Well, maybe enough of one to ask why a lion was on the radio, but not enough of one to rule out the possibility.

Of course, the next question was “what’s a call?”… and why is Dave taking it from this other guy (who we now know not to be a lion). I gave her the answers she sought as we continued home, all the while chuckling to myself about the lion on the radio who was thanking dave ramsey for shaking his paw.