Uh, no. An X-ray photon and an infra-red photon have the same velocity, c. They have different frequencies. Neither will escape a black hole, which is pretty much defined as a body having an escape velocity greater than c.
That's because C deals with how computers actually think.
No. C presents a highly idealised representation of how computers actually think. According to C, there are two types of data storage; disks and memory. One is accessed through fopen() etc., and the other through malloc() and its kin.
However, on any modern OS, calling fopen(), read() may well return me data that was residing in-memory in a file system cache, and a call to malloc() may well result in a pointer to data that's actually residing on the harddrive in the swap file. Then throw in things like L1, L2 cache into the mix, and we realise that we are writing code against an imaginary, idealised machine. I'd suggest that even by the time we reach 'C', we're in the realm of 'nothing at all to do with how the processor works'.
So why not keep going, and build newer storage models that don't make an arbitrary division between 'memory' and 'disk', and certainly don't force these upon the end-user?
Some of the nicest programs I've used recently, such as Adobe Lightroom, have done away with the concept of a 'Save' button entirely - changes the user makes to data are immediately reflected in the SQLite datastore. The end user, who's not a programmer, doesn't need to maintain a mental model of memory, filesystems etc.
Given that the whole point of a union is to create a monopoly on one form of labour, I'd have to say the idea is laughable.
I think most slashdotters agree that monopolies=bad, and in a field as fluid and as locationally independent as IT, I'd add that monopoly of labour = impossible, as well. This isn't coal mining or manufacturing, where it might be feasible to completely control the labour supply in a city.
As a provider of IT services, I'm quite content to sell my services to the highest bidder, and I've had no problems funding a comfortable lifestyle doing so.
As a consumer of IT services, I glad when I have the freedom to choose the best individual or company for the services I want. It's bad enough when there's only a single provider of, say, operating systems or cable internet available. Restricting the supply of labour further would not improve things.
I think this is really the most important point, and not enough people are making it. Imagine your a doctor, medical researcher etc., and your laptop contains confidential healthcare information about patients. Under the UK data protection act, or HIPAA in the US, you'd be taking huge legal risks allowing a third party uncontrolled access to the data. Furthermore, you'd be immediately violating basic ethical principles regarding protecting patient's privacy. IANAL, but it seems to me that the customs agents are requiring travelers to break the law by disclosing data.
And absolutely impossible to finish, even with cheats, if I recall correctly. Granted, it wasn't obvious what the goal of the game even was. But yes, I remember spending many hours throwing Coronium boulders around...
How does this behaviour interact with data-privacy statutes, such as HIPAA? For example, imagine you're a doctor carrying a laptop with patient data on it. Now you have a responsibility to protect that data and only transfer it to appropriately authorised bodies, with your patients consent. Are the border agencies acceptable bodies? What about if you're, say, a UK doctor entering the US? Wouldn't the Data Protection Act be violated?
No. If you throw something from a satellite in a circular orbit, giving it a small 'downward' velocity component, the object will just end up in a slightly elliptical orbit.
One way of thinking about orbits is that a satellite is perpetually falling towards the earth, because of gravity, but also perpetually missing, because of the lateral velocity component.
To make the paper plane de-orbit, you could throw it in the opposite direction to the ISS at the same velocity as the ISS is travelling: 27 500 km/h. Then the plane won't have any lateral velocity component, and will fall straight down.
Why is laying nuclear mines a suicide mission? Just a question of a long enough time-delay, surely? You'd only need one sub, working its way along the coast. And as for avoiding detection, Boomers have gotten rather good at that over the last 50 years.
A guitar has several tons of tension on its neck No it doesn't. Each string has a few kilograms of tension, depending of course on string thickness and mass per unit length. Total tension can typically be in the range of around 50 kg.
Not to blow my own horn, but I happen to think the DICOM medical imaging libraries that I maintain score pretty highly on code reuse, RAII, exceptions and general maintainability.
The boost libraries tend to be a pleasure to work with. BOOST::Python especially continues to surprise me by how much it 'just works'. That said, I haven't had much need to look at the source code itself, but there seems to be a strong desire in the boost community to do things in as clean a way as possible.
Pretty much every book I enter I get 'unsuggested' a book that I've both read and enjoyed!
Alan Moore's 'Watchmen' gives me Brian McLaren's works, which I love.
Brian McLaren's 'The Last Word and the Word After That' gives me 'Good Omens', by Pratchett and Gaiman, which I've read more times than I can remember.
'Small Gods', by Pratchett gives me 'The Jesus I Never Knew', by Yancey. Again, an excellent, profound book.
And then Yancey's work, in turn, leads me to Douglas Adams, who needs no defense!
What's the message here? That I'm unique in being intrigued both postmodern explorations of faith as well as surreal British fantasy works? Surely there must be others like me out there? Or is there really such a great literary secular/sacred divide that readers on either side dare not cross?
Tianamen Square may have been 16 years ago, but a similar massacre occurred in Uzbekistan less than a year ago. I wonder only certain events stick in our collective consciousness? I'm guessing the fact that Tianamen was broadcast live on TV has something to do with it.
I've already been bitten by this - I wrote a perfectly short C++ program as a tutorial for a friend, using VC++ 2003, but when he tried to compile it on VC++ 2005 it gave this warning:
warning C4996: 'std::_Transform' was declared deprecated
which implies, at least to the novice developer, that the use of the standard c++ algorithm library is no longer considered appropriate practice. This is extremely annoying and misleading. One of the major strengths of C++ is that you can extend it almost limitlessly without changing the underlying language. As far as I can see, for every extension that people have tried to add to the language to support a particular paradigm, it has been shown that the same effect can be achieved without going beyond the bounds of the language.
For example, Qt introduces signals and slots as an extension, but the same effect can be achieved with libsigc++ or boost::signals, making intelligent use of the template system. Smart pointers and garbage collection have been demonstrated by boost::shared_ptr and so on.
I understand that in the past weaknesses in implementations of C++ made some of these extensions necessary, but now that we have compliant compilers that actually implement almost all of the language standard, there are less and less reasons to create proprietary extensions to it.
Surely this is your employer's problem, not yours, given that they're the ones who've implemented a faulty security system?
As it's impeding your ability to do your job, it's costing them money and so is in their best interests to fix.
Editor, spreadsheet, BBC Micro compatibility, about 10 lines of screen space IIRC, what more could one want? I still have fond memories of my first laptop.
Good luck in your search. Let me know when you find one. I know I have a long way to go to the point of 'truly understanding and practicing' his teaching.
Especially all that stuff about caring for and giving to people you really can't stand and to those whom you have no chance of getting anything back from. I think there's maybe one or two people in each generation that truly get this. You occasionally get people like Mother Theresa sacrificing their life to caring for the least attractive members of society, which I think is truly Christ-like, but like you say, they are rare people indeed.
Perhaps we should pray for the grace to become like this.
I have to disagree with you here. I've been playing around with XUL for the last couple of months, and I'm finding it a very nice gui development toolkit. Having previously used: MFC, WTL, QT, Tcl/Tk, wxWidgets (and even Visual Basic), XUL is now my current toolkit of choice.
That said, I haven't pushed it very far yet, and I haven't tried doing anything with XPCOM, though I have used xml-rpc to talk to remote components.
Give it a try - I think that in XUL the open source community is sitting on a goldmine whose potential hasn't been fully realised.
Thanks to the postgresql team for providing this great product. I've been using postgresql for a couple of years now, and the release candidates of version 8 for the last month or so. (It's good to finally have a windows port!)
Apart from the initial learning curve, I have exactly zero complaints with postgres - it always does exactly what it says it will. I have no qualms trusting vital data to it. Combined with the excellent pqxx c++ bindings library you can build robust applications with very tightly controlled data integrity - for example (shameless plug) my medical imaging server
Anyways, what are you waiting for? Go download it - you won't be disappointed.
One of Mozilla's greatest strengths is not as just a web-browser but as a cross-platform application development platform.
Just try playing around with XUL a little. It's surprising what it can do. I'm just starting out with it, but having worked my way through MFC, QT, TCL/TK, WTL, GTK++, FLTK, wxWidgets etc. etc. in search of the One True UI Library, I'm liking what I've seen so far.
As a personal side note, I think the hierchical, shapeless key/value database design is an incredibly inelegant kludge. People are still blatantly ignoring (and misunderstanding) the best theoretical model for information storage ever invented, Codd's relational model, which is also pretty much the only theoretical model invented.
Fortunately, some people "get" it; the relational nature of RDF triples is one such recent example, and I would rather see RDF (although not necessarily its XML syntax) adopted, because it's such a simple, elegant, extensible system.
I agree completely. A vast number of programming and systems maintainence problems basically come down to poorly thought out data models, and especially lack of proper referential integrity enforcement. All these questions about software installation/de-installation, orphanned entries and so on would simply not be an issue in a system based on a relational database with well thought-out CASCADEs and so on.
It's been 20 years since Codd's rules - you'd think we would have got it by now. (Although I have no idea how his concepts map to a networked world where there's no single arbiter of 'truth', and data is spread across multiple systems. I suppose RDF is a step in that direction, but I'm not very familiar with it yet.)
Slashdot Mirror
Uh, no. An X-ray photon and an infra-red photon have the same velocity, c. They have different frequencies. Neither will escape a black hole, which is pretty much defined as a body having an escape velocity greater than c.
That's because C deals with how computers actually think.
No. C presents a highly idealised representation of how computers actually think. According to C, there are two types of data storage; disks and memory. One is accessed through fopen() etc., and the other through malloc() and its kin.
However, on any modern OS, calling fopen(), read() may well return me data that was residing in-memory in a file system cache, and a call to malloc() may well result in a pointer to data that's actually residing on the harddrive in the swap file. Then throw in things like L1, L2 cache into the mix, and we realise that we are writing code against an imaginary, idealised machine. I'd suggest that even by the time we reach 'C', we're in the realm of 'nothing at all to do with how the processor works'.
So why not keep going, and build newer storage models that don't make an arbitrary division between 'memory' and 'disk', and certainly don't force these upon the end-user?
Some of the nicest programs I've used recently, such as Adobe Lightroom, have done away with the concept of a 'Save' button entirely - changes the user makes to data are immediately reflected in the SQLite datastore. The end user, who's not a programmer, doesn't need to maintain a mental model of memory, filesystems etc.
Given that the whole point of a union is to create a monopoly on one form of labour, I'd have to say the idea is laughable.
I think most slashdotters agree that monopolies=bad, and in a field as fluid and as locationally independent as IT, I'd add that monopoly of labour = impossible, as well. This isn't coal mining or manufacturing, where it might be feasible to completely control the labour supply in a city.
As a provider of IT services, I'm quite content to sell my services to the highest bidder, and I've had no problems funding a comfortable lifestyle doing so.
As a consumer of IT services, I glad when I have the freedom to choose the best individual or company for the services I want. It's bad enough when there's only a single provider of, say, operating systems or cable internet available. Restricting the supply of labour further would not improve things.
I think this is really the most important point, and not enough people are making it. Imagine your a doctor, medical researcher etc., and your laptop contains confidential healthcare information about patients. Under the UK data protection act, or HIPAA in the US, you'd be taking huge legal risks allowing a third party uncontrolled access to the data. Furthermore, you'd be immediately violating basic ethical principles regarding protecting patient's privacy. IANAL, but it seems to me that the customs agents are requiring travelers to break the law by disclosing data.
And absolutely impossible to finish, even with cheats, if I recall correctly. Granted, it wasn't obvious what the goal of the game even was. But yes, I remember spending many hours throwing Coronium boulders around...
How does this behaviour interact with data-privacy statutes, such as HIPAA? For example, imagine you're a doctor carrying a laptop with patient data on it. Now you have a responsibility to protect that data and only transfer it to appropriately authorised bodies, with your patients consent. Are the border agencies acceptable bodies? What about if you're, say, a UK doctor entering the US? Wouldn't the Data Protection Act be violated?
Any lawyer wannabes care to chime in?
No. If you throw something from a satellite in a circular orbit, giving it a small 'downward' velocity component, the object will just end up in a slightly elliptical orbit.
One way of thinking about orbits is that a satellite is perpetually falling towards the earth, because of gravity, but also perpetually missing, because of the lateral velocity component.
To make the paper plane de-orbit, you could throw it in the opposite direction to the ISS at the same velocity as the ISS is travelling: 27 500 km/h. Then the plane won't have any lateral velocity component, and will fall straight down.
Why is laying nuclear mines a suicide mission? Just a question of a long enough time-delay, surely? You'd only need one sub, working its way along the coast. And as for avoiding detection, Boomers have gotten rather good at that over the last 50 years.
Sorry, that should presumably 500N, i.e. equivalent to 50 kg hanging from the strings under normal gravity.
Not to blow my own horn, but I happen to think the DICOM medical imaging libraries that I maintain score pretty highly on code reuse, RAII, exceptions and general maintainability.
The boost libraries tend to be a pleasure to work with. BOOST::Python especially continues to surprise me by how much it 'just works'. That said, I haven't had much need to look at the source code itself, but there seems to be a strong desire in the boost community to do things in as clean a way as possible.
Pretty much every book I enter I get 'unsuggested' a book that I've both read and enjoyed!
Alan Moore's 'Watchmen' gives me Brian McLaren's works, which I love.
Brian McLaren's 'The Last Word and the Word After That' gives me 'Good Omens', by Pratchett and Gaiman, which I've read more times than I can remember.
'Small Gods', by Pratchett gives me 'The Jesus I Never Knew', by Yancey. Again, an excellent, profound book.
And then Yancey's work, in turn, leads me to Douglas Adams, who needs no defense!
What's the message here? That I'm unique in being intrigued both postmodern explorations of faith as well as surreal British fantasy works? Surely there must be others like me out there? Or is there really such a great literary secular/sacred divide that readers on either side dare not cross?
Tianamen Square may have been 16 years ago, but a similar massacre occurred in Uzbekistan less than a year ago. I wonder only certain events stick in our collective consciousness? I'm guessing the fact that Tianamen was broadcast live on TV has something to do with it.
For example, Qt introduces signals and slots as an extension, but the same effect can be achieved with libsigc++ or boost::signals, making intelligent use of the template system. Smart pointers and garbage collection have been demonstrated by boost::shared_ptr and so on.
I understand that in the past weaknesses in implementations of C++ made some of these extensions necessary, but now that we have compliant compilers that actually implement almost all of the language standard, there are less and less reasons to create proprietary extensions to it.
Surely this is your employer's problem, not yours, given that they're the ones who've implemented a faulty security system? As it's impeding your ability to do your job, it's costing them money and so is in their best interests to fix.
You can do this in a considerably nicer fashion using the boost::bind and boost::function libraries, so for example
std::bind2nd(std::ptr_fun(f), 5)
becomes
bind(f, 5, _1)
That said, Python and especially Haskell still have much nicer syntax for binding functions.
Compare
std::bind1st(std::plus<int>(),1);
in c++
with
(+1)
in Haskell!
You were at IC to? Which year? (I was physics, 96-99)
Editor, spreadsheet, BBC Micro compatibility, about 10 lines of screen space IIRC, what more could one want? I still have fond memories of my first laptop.
Good luck in your search. Let me know when you find one. I know I have a long way to go to the point of 'truly understanding and practicing' his teaching.
Especially all that stuff about caring for and giving to people you really can't stand and to those whom you have no chance of getting anything back from. I think there's maybe one or two people in each generation that truly get this. You occasionally get people like Mother Theresa sacrificing their life to caring for the least attractive members of society, which I think is truly Christ-like, but like you say, they are rare people indeed.
Perhaps we should pray for the grace to become like this.
I have to disagree with you here. I've been playing around with XUL for the last couple of months, and I'm finding it a very nice gui development toolkit. Having previously used: MFC, WTL, QT, Tcl/Tk, wxWidgets (and even Visual Basic), XUL is now my current toolkit of choice.
That said, I haven't pushed it very far yet, and I haven't tried doing anything with XPCOM, though I have used xml-rpc to talk to remote components.
Give it a try - I think that in XUL the open source community is sitting on a goldmine whose potential hasn't been fully realised.
Apparently pi has just become rational...
Thanks to the postgresql team for providing this great product. I've been using postgresql for a couple of years now, and the release candidates of version 8 for the last month or so. (It's good to finally have a windows port!)
Apart from the initial learning curve, I have exactly zero complaints with postgres - it always does exactly what it says it will. I have no qualms trusting vital data to it. Combined with the excellent pqxx c++ bindings library you can build robust applications with very tightly controlled data integrity - for example (shameless plug) my medical imaging server
Anyways, what are you waiting for? Go download it - you won't be disappointed.
One of Mozilla's greatest strengths is not as just a web-browser but as a cross-platform application development platform.
Just try playing around with XUL a little. It's surprising what it can do. I'm just starting out with it, but having worked my way through MFC, QT, TCL/TK, WTL, GTK++, FLTK, wxWidgets etc. etc. in search of the One True UI Library, I'm liking what I've seen so far.
I agree completely. A vast number of programming and systems maintainence problems basically come down to poorly thought out data models, and especially lack of proper referential integrity enforcement. All these questions about software installation/de-installation, orphanned entries and so on would simply not be an issue in a system based on a relational database with well thought-out CASCADEs and so on.
It's been 20 years since Codd's rules - you'd think we would have got it by now. (Although I have no idea how his concepts map to a networked world where there's no single arbiter of 'truth', and data is spread across multiple systems. I suppose RDF is a step in that direction, but I'm not very familiar with it yet.)