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  • Problems using easing equations in C# XNA

    - by codinghands
    I'm having some trouble using the easing equations suggested by Robert Penner for ActionScript (http://www.robertpenner.com/easing/, and a Flash demo here) in my C# XNA game. Firstly, what is the definition of the following variables passed in as arguments to each equation? float t, float b, float c, float d I'm currently calculating the new X position of a sprite in the Update() loop, however even for the linear tween equation I'm getting some odd results. I'm using the following values: float t = gameTime.TotalGameTime.TotalMilliseconds; float d = 8000f; float b = x.Position.X; float c = (ScreenManager.Game.GraphicsDevice.Viewport.Width >> 1) - (x.Position.X + x.frameSize.X / 2); And this equation for linear easing: float val = c*t/d + b;

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  • How to implement JQuery easing into this window scroll movement function?

    - by Mohammad
    With this code I've been able to capture the mousewheel movement and apply it to the horizontal scroll bars instead of the vertical default. $('html').bind('mousewheel', function(event, delta) { window.parent.scrollBy(-120 * delta, 0); return false; }); Is there any way that I could add this jQuery easing animation to the scroll movement? jQuery.extend( jQuery.easing, { easeInOutBack: function (x, t, b, c, d, s) { if (s == undefined) s = 1.70158; if ((t/=d/2) < 1) return c/2*(t*t*(((s*=(1.525))+1)*t - s)) + b; return c/2*((t-=2)*t*(((s*=(1.525))+1)*t + s) + 2) + b; } }); Thank you so much in advance!

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  • Functions inside page using Razor View Engine – ASP.NET MVC

    - by hajan
    As we already know, Razor is probably the best view engine for ASP.NET MVC so far. It keeps your code fluid and very expressive. Besides the other functionalities Razor has, it also supports writing local functions. If you want to write a function, you can’t just open new @{ } razor block and write it there… it won’t work. Instead, you should specify @functions { } so that inside the brackets you will write your own C#/VB.NET functions/methods. Lets see an example: 1. I have the following loop that prints data using Razor <ul> @{     int N = 10;     for (int i = 1; i<=N; i++)     {         <li>Number @i</li>     }     } </ul> This code will print the numbers from 1 to 10: Number 1 Number 2 Number 3 Number 4 Number 5 Number 6 Number 7 Number 8 Number 9 Number 10 So, now lets write a function that will check if current number is even, if yes… add Even before Number word. Function in Razor @functions{     public bool isEven(int number)     {         return number % 2 == 0 ? true : false;     } } The modified code which creates unordered list is: <ul> @{     int N = 10;     for (int i = 1; i<=N; i++)     {         if (isEven(@i)) {             <li>Even number @i</li>         }         else {             <li>Number @i</li>         }                 }             } </ul> As you can see, in the modified code we use the isEven(@i) function to check if the current number is even or not… The result is: Number 1 Even number 2 Number 3 Even number 4 Number 5 Even number 6 Number 7 Even number 8 Number 9 Even number 10 So, the main point of this blog was to show how you can define your own functions inside page using Razor View Engine. Of course you can define multiple functions inside the same @functions { } defined razor statement. The complete code: @{     Layout = null; } <!DOCTYPE html> <html> <head>     <title>ASP.NET MVC - Razor View Engine :: Functions</title> </head> <body>     <div>         <ul>         @{             int N = 10;             for (int i = 1; i<=N; i++)             {                 if (isEven(@i)) {                     <li>Even number @i</li>                 }                 else {                     <li>Number @i</li>                 }                         }                     }         </ul>         @functions{             public bool isEven(int number)             {                 return number % 2 == 0 ? true : false;             }         }     </div> </body> </html> Hope you like it. Regards, Hajan

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  • Network programming under windows: is WSA functions can be more complete than pSock functions [on hold]

    - by Kane
    I plan to make a set of classic socket functions to simplify their usages. Since i work under windows and linux indifferently i usually make it portable (it's not my first version of this set of functions), but i want to do something different this time and dedicate one version to windows, and one other to linux. With that i wonder for the windows version, if the WSA* functions can have any interest using them instead of the psock ones. I have found nothing about a comparison between them, so if any of you have any idea, suggestion, link or benchmark ?

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  • helper functions as static functions or procedural functions?

    - by fayer
    i wonder if one should create a helper function in a class as a static function or just have it declared as a procedural function? i tend to think that a static helper function is the right way to go cause then i can see what kind of helper function it is eg. Database::connect(), File::create(). what is best practice?

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  • F#: any way to use member functions as unbound functions?

    - by gatoatigrado
    Is there a way to extract member functions, and use them as F# functions? I'd like to be able to write the following: mystring |> string.Split '\n' |> Array.filter (string.Length >> (=) 0 >> not) The code above works if you [let] let mystring = "a c\nb\n" let stringSplit (y:char) (x:string) = x.Split(y) let stringLength (x:string) = x.Length mystring |> stringSplit '\n' |> Array.filter (stringLength >> (=) 0 >> not)

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  • Python — Time complexity of built-in functions versus manually-built functions in finite fields

    - by stackuser
    Generally, I'm wondering about the advantages versus disadvantages of using the built-in arithmetic functions versus rolling your own in Python. Specifically, I'm taking in GF(2) finite field polynomials in string format, converting to base 2 values, performing arithmetic, then output back into polynomials as string format. So a small example of this is in multiplication: Rolling my own: def multiply(a,b): bitsa = reversed("{0:b}".format(a)) g = [(b<<i)*int(bit) for i,bit in enumerate(bitsa)] return reduce(lambda x,y: x+y,g) Versus the built-in: def multiply(a,b): # a,b are GF(2) polynomials in binary form .... return a*b #returns product of 2 polynomials in gf2 Currently, operations like multiplicative inverse (with for example 20 bit exponents) take a long time to run in my program as it's using all of Python's built-in mathematical operations like // floor division and % modulus, etc. as opposed to making my own division, remainder, etc. I'm wondering how much of a gain in efficiency and performance I can get by building these manually (as shown above). I realize the gains are dependent on how well the manual versions are built, that's not the question. I'd like to find out 'basically' how much advantage there is over the built-in's. So for instance, if multiplication (as in the example above) is well-suited for base 10 (decimal) arithmetic but has to jump through more hoops to change bases to binary and then even more hoops in operating (so it's lower efficiency), that's what I'm wondering. Like, I'm wondering if it's possible to bring the time down significantly by building them myself in ways that maybe some professionals here have already come across.

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  • What can procs and lambdas do that functions can't in ruby

    - by SecurityGate
    I've been working in Ruby for the last couple weeks, and I've come to the subject of procs, lambdas and blocks. After reading a fair share of examples from a variety of sources, I don't how they're much different from small, specialized functions. It's entirely possible that the examples I've read aren't showing the power behind procs and lambdas. def zero_function(x) x = x.to_s if x.length == 1 return x = "0" + x else return x end end zero_lambda = lambda {|x| x = x.to_s if x.length == 1 return x = "0" + x else return x end } zero_proc = Proc.new {|x| x = x.to_s if x.length == 1 puts x = "0" + x else puts x end } puts zero_function(4) puts zero_lambda.call(3) zero_proc.call(2) This function, proc, and lambda do the exact same thing, just slightly different. Is there any reason to choose one over another?

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  • Non-trivial functions that operate on any monad

    - by Strilanc
    I'm looking for examples of interesting methods that take an arbitrary monad and do something useful with it. Monads are extremely general, so methods that operate on monads are widely applicable. On the other hand, methods I know of that can apply to any monad tend to be... really, really trivial. Barely worth extracting into a function. Here's a really boring example: joinTwice. It just flattens an m m m t into an m t: join n = n >>= id joinTwice n = (join . join) n main = print (joinTwice [[[1],[2, 3]], [[4]]]) -- prints [1,2,3,4] The only non-trivial method for monads that I know of is bindFold (see my answer below). Are there more?

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  • Functional Methods on Collections

    - by GlenPeterson
    I'm learning Scala and am a little bewildered by all the methods (higher-order functions) available on the collections. Which ones produce more results than the original collection, which ones produce less, and which are most appropriate for a given problem? Though I'm studying Scala, I think this would pertain to most modern functional languages (Clojure, Haskell) and also to Java 8 which introduces these methods on Java collections. Specifically, right now I'm wondering about map with filter vs. fold/reduce. I was delighted that using foldRight() can yield the same result as a map(...).filter(...) with only one traversal of the underlying collection. But a friend pointed out that foldRight() may force sequential processing while map() is friendlier to being processed by multiple processors in parallel. Maybe this is why mapReduce() is so popular? More generally, I'm still sometimes surprised when I chain several of these methods together to get back a List(List()) or to pass a List(List()) and get back just a List(). For instance, when would I use: collection.map(a => a.map(b => ...)) vs. collection.map(a => ...).map(b => ...) The for/yield command does nothing to help this confusion. Am I asking about the difference between a "fold" and "unfold" operation? Am I trying to jam too many questions into one? I think there may be an underlying concept that, if I understood it, might answer all these questions, or at least tie the answers together.

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  • Easing the Journey to the Private Cloud with Oracle Consulting

    - by MichaelM-Oracle
    By Sanjai Marimadaiah, Senior Director, Strategy & Business Development – Cloud Solutions, Oracle Consulting Services Business leaders are now leading the charge on how their firms can profit from cloud solutions. Agility and innovation are becoming the primary drivers of the business case for the cloud, even more than the anticipated cost savings. Leaders need to find the right strategy and optimize the use of cloud-based applications across their enterprise-computing infrastructure. The Problem – Current State With prevalent IT practices, many organizations find that they run multiple IT solutions serving similar business needs. This has led to the proliferation of technology stacks, for example: Oracle 10g on Sun T4 running Solaris 9; Oracle 11g on Exadata running Linux; or Oracle 12c on commodity x86 servers. This variance has a huge impact on an organization’s agility and expenses, and requires IT professionals with varied skills as well as on-going training for different systems and tools. Fortunately there is a practical business strategy to overcome this unneeded redundancy. Thus begins a journey to the right cloud computing solution. The Solution – Cloud Services from Oracle Consulting Services (OCS) Oracle Consulting Services (OCS ) works closely with our clients as trusted advisors to proactively respond to business needs and IT concerns. OCS understands that making the transition to cloud solutions begins with a strategic conversation, based on its deep expertise for successfully completing private cloud service engagements with several companies. For a journey to the cloud, Oracle Consulting Services leads the client through four phases– standardization, consolidation, service delivery, and enterprise cloud – to achieve optimal returns. Phase 1 - Standardization Oracle Consulting Services (OCS) works with clients to evaluate their business requirements and propose a set of standard solutions stacks for various IT solutions. This is an opportune time to evaluate cloud ready solutions, such as Oracle 12c, Oracle Exadata, and the Oracle Database Appliance (ODA). The OCS consultants, together with the delivery team, then turn to upgrading and migrating existing solution stacks to standardized offerings. OCS has the expertise and tools to complete this stage in a fraction of the time required by other IT services companies. Clients quickly realize cost savings in tools, processes, and type/number of resources required. This standardization also improves agility of the IT organizations and their abilities to respond to the needs of various business units. Phase 2 - Consolidation During the consolidation phase, OCS consultants programmatically consolidate hundreds of databases into a smaller number of servers to improve utilization, reduce floor space, and optimize maintenance costs. Consolidation helps clients realize huge savings in CapEx investments and shrink OpEx costs. The use of engineered systems, such as Oracle Exadata, greatly reduces the client’s risk of moving to a new solution stack. OCS recommends clients to pursue Phase 1 (Standardization) and Phase 2 (Consolidation) simultaneously to reduce the overall time, effort, and expense of the cloud journey. Phase 3 - Service Delivery Once a client is on a path of standardization and consolidation, OCS consultants create Service Catalogues based on the SLAs requirements and the criticality of the solutions. The number and types of Service Catalogues (Platinum, Gold, Silver, Bronze, etc.) vary from client to client. OCS consultants also implement a variety of value-added cloud solutions, including monitoring, metering, and charge-back solutions. At this stage, clients are able to achieve a high level of understanding in their cloud journey. Their IT organizations are operating efficiently and are more agile in responding to the needs of business units. Phase 4 - Enterprise Cloud In the final phase of the cloud journey, the economics of the IT organizations change. Business units can request services on-demand; applications can be deployed and consumed on a pay-as-you-go model. OCS has the expertise and capabilities to establish processes, programs, and solutions required for IT organizations to transform how they interact with business units. The Promise of Cloud Solutions Depending the size and complexity of their business model, some clients are able to abbreviate some phases of their cloud journey. Cloud solutions are still evolving and there is rapid pace of innovation to transform how IT organizations operate. The lesson is clear. Cloud solutions hold a lot of promise for business agility. Business leaders can now leverage an additional set of capabilities and services. They can ramp up their pace of innovation. With cloud maturity, they can compete more effectively in their respective markets. But there are certainly challenges ahead. A skilled consulting services partner can play a pivotal role as a trusted advisor in the successful adoption of cloud solutions. Oracle Consulting Services has expertise and a portfolio of services to help clients succeed on their journey to the cloud.

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  • Why isn't there a typeclass for functions?

    - by Steve314
    I already tried this on Reddit, but there's no sign of a response - maybe it's the wrong place, maybe I'm too impatient. Anyway... In a learning problem I've been messing around with, I realised I needed a typeclass for functions with operations for applying, composing etc. Reasons... It can be convenient to treat a representation of a function as if it were the function itself, so that applying the function implicitly uses an interpreter, and composing functions derives a new description. Once you have a typeclass for functions, you can have derived typeclasses for special kinds of functions - in my case, I want invertible functions. For example, functions that apply integer offsets could be represented by an ADT containing an integer. Applying those functions just means adding the integer. Composition is implemented by adding the wrapped integers. The inverse function has the integer negated. The identity function wraps zero. The constant function cannot be provided because there's no suitable representation for it. Of course it doesn't need to spell things as if it the values were genuine Haskell functions, but once I had the idea, I thought a library like that must already exist and maybe even using the standard spellings. But I can't find such a typeclass in the Haskell library. I found the Data.Function module, but there's no typeclass - just some common functions that are also available from the Prelude. So - why isn't there a typeclass for functions? Is it "just because there isn't" or "because it's not so useful as you think"? Or maybe there's a fundamental problem with the idea? The biggest possible problem I've thought of so far is that function application on actual functions would probably have to be special-cased by the compiler to avoid a looping problem - in order to apply this function I need to apply the function application function, and to do that I need to call the function application function, and to do that...

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  • Add an easing to jQuery animate() function.

    - by user348250
    Hello! I'm triying to add an easing function to this code. So I replaced "swing" with "easeInOutQuint" (for example) but it's not working. I'm using jquery 1.4.2 and jquery easing 1.3 downloaded from here (http://gsgd.co.uk/sandbox/jquery/easing/) Any help will be greatly appreciated! Thank you! $(window).load(function() { $('.trigger').click(function() { $('.panel').animate({ width: ['toggle', 'swing'], height: ['toggle', 'swing'], opacity: 'toggle' }, 190, 'linear', function() { }); });

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  • How to add ease to this, with jQuery Easing plugin.

    - by user1691441
    I've asked this question previously before, and had a bit of help, but my lack of jQuery skills still didn't accomplish the job. I was wondering if anyone else could help me out with this. I've tried adding easing: "easeIn" right after the duration section, but still didn't work for me. if anyone could help me out that would be wonderful. I'm using the jquery easing plugin $(function() { function scroll(direction) { var scroll, i, positions = [], here = $(window).scrollTop(), collection = $('.part'); collection.each(function() { positions.push(parseInt($(this).offset()['top'],10)); }); for(i = 0; i < positions.length; i++) { if (direction == 'next' && positions[i] > here) { scroll = collection.get(i); break; } if (direction == 'prev' && i > 0 && positions[i] >= here) { scroll = collection.get(i-1); break; } } if (scroll) { $.scrollTo(scroll, { duration: 350 }); } return false; } $("#next,#prev").click(function() { return scroll($(this).attr('id')); }); $(".scrolltoanchor").click(function() { $.scrollTo($($(this).attr("href")), { duration: 350 }); return false; }); });

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  • jquery slideshow/cycle with easing not working

    - by Blankman
    Here is my code, for some reason it isn't working when I add the easing option. It works fine with 'fade'. <script src="jquery.easing.1.3.js" type="text/javascript"></script> <script src="jquery.cycle.all.min.js" type="text/javascript"></script> <style> .pics { height: 383px; width: 582px; padding: 0; margin: 0; } .pics img { padding: 15px; border: 1px solid #ccc; background-color: #eee; width: 550px; height: 350px; top: 0; left: 0 } </style> <div id="cycle" class="pics"> <img src="/images/1.png" width="550" height="350" /> <img src="/images/2.jpg" width="550" height="350"/> </div> <script type="text/javascript"> $().ready(function() { $('#cycle').cycle({ fx: 'scrollDown', easing: 'bounceout', delay: -2000 }); }); </script> Is there something else I have to do, to tell the cycle plugin I have easing?

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  • c++ class member functions selected by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched stackoverflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instatiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state info was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice?

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  • c++ class member functions instatiated by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched stackoverflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state info was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (vc++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice?

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  • C++ class member functions instantiated by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched Stack Overflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state information was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (VC++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice?

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  • trouble accessing non-static functions from static functions in AS3

    - by Dogmatixed
    I have a class containing, among other things, a drop down menu. With the aim of saving space, and since the contents of the menu will never change, I've made a static DataProvider for the whole class that populates each instances menu. I was hoping to populate the list with actual functions like so: tmpArr.push({label:"Details...", funct:openDetailsMenu, args:""}); and then assign tmpArr to the DataProvider. Because the DataProvider is static the function that contains that code also needs to be static, but the functions in the array are non-static. At first it didn't seem like a problem, because when the user clicks on a menu item the drop down menu can call a non-static "executeFunction(funct, args)" on its parent. However, when I try to compile, the static function setting up the DataProvider it can't find the non-static functions being passed. If the compiler would just trust me the code would work fine! The simple solution is to just pass strings and use a switch statement to call functions based on that, but that's big, ugly, inelegant, and difficult to maintain, especially if something inherits from this class. The simpler solution is to just make the DataProvider non-static, but I'm wondering if anyone else has a good way of dealing with this? Making the static function able to see its non-static brethren? Thanks.

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  • Usefulness of Toggle functions

    - by roygbiv
    Is it better to write functions that explicitly do something (i.e. HideForm/ShowForm etc...) or is it better to write 'Toggle' type functions (i.e. ToggleVisibility)? I find Toggle type functions awkard because it's hard to track the state by reading the code. In what situations is a toggle type function useful?

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  • Are first-class functions a substitute for the Strategy pattern?

    - by Prog
    The Strategy design pattern is often regarded as a substitute for first-class functions in languages that lack them. So for example say you wanted to pass functionality into an object. In Java you'd have to pass in the object another object which encapsulates the desired behavior. In a language such as Ruby, you'd just pass the functionality itself in the form of an annonymous function. However I was thinking about it and decided that maybe Strategy offers more than a plain annonymous function does. This is because an object can hold state that exists independently of the period when it's method runs. However an annonymous function by itself can only hold state that ceases to exist the moment the function finishes execution. So my question is: when using a language that features first-class functions, would you ever use the Strategy pattern (i.e. encapsulate the functionality you want to pass around in an explicit object), or would you always use an annonymous function? When would you decide to use Strategy when you can use a first-class function?

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  • Class member functions instantiated by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched Stack Overflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state information was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (VC++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice? UPDATE: Here's another try at explaining it. I want the user to be able to fill out an order (manifest) for a custom optimizer, something like ordering off of a Chinese menu - one from column A, one from column B, etc.. Waiter, from column A (updaters), I'll have the BFGS update with Cholesky-decompositon sauce. From column B (line-searchers), I'll have the cubic interpolation line-search with an eta of 0.4 and a rho of 1e-4, please. Etc... UPDATE: Okay, okay. Here's the playing-around that I've done. I offer it reluctantly, because I suspect it's a completely wrong-headed approach. It runs okay under vc++ 2008. #include <boost/utility.hpp> #include <boost/type_traits/integral_constant.hpp> namespace dj { struct CBFGS { void bar() {printf("CBFGS::bar %d\n", data);} CBFGS(): data(1234){} int data; }; template<class T> struct is_CBFGS: boost::false_type{}; template<> struct is_CBFGS<CBFGS>: boost::true_type{}; struct LMQN {LMQN(): data(54.321){} void bar() {printf("LMQN::bar %lf\n", data);} double data; }; template<class T> struct is_LMQN: boost::false_type{}; template<> struct is_LMQN<LMQN> : boost::true_type{}; struct default_optimizer_traits { typedef CBFGS update_type; }; template<class traits> class Optimizer; template<class traits> void foo(typename boost::enable_if<is_LMQN<typename traits::update_type>, Optimizer<traits> >::type& self) { printf(" LMQN %lf\n", self.data); } template<class traits> void foo(typename boost::enable_if<is_CBFGS<typename traits::update_type>, Optimizer<traits> >::type& self) { printf("CBFGS %d\n", self.data); } template<class traits = default_optimizer_traits> class Optimizer{ friend typename traits::update_type; //friend void dj::foo<traits>(typename Optimizer<traits> & self); // How? public: //void foo(void); // How??? void foo() { dj::foo<traits>(*this); } void bar() { data.bar(); } //protected: // How? typedef typename traits::update_type update_type; update_type data; }; } // namespace dj int main_() { dj::Optimizer<> opt; opt.foo(); opt.bar(); std::getchar(); return 0; }

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  • Autohotkey script multiple functions

    - by Vince
    Is it possible to use this bottom script but add a second hotkey and function that goes with it. ;DoOver.ini ;[Settings] ;record={LCtrl}{F12} ;hotkey to start and stop recording ;playback={LCtrl}{F5} ;hotkey to start playback ;keydelay=10 ;ms to wait after sending a keypress ;windelay=100 ;ms to wait after activating a window ;movemouseafter=1 ;move the mouse to original pos after playback 1=yes 0=no [Settings] record={LCtrl}{F12} playback={LCtrl}{F5} keydelay=10 windelay=100 movemouseafter=1 macro={WinActive}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{LCTRL Down}{Right}{Right}{LCTRL Up}{LSHIFT Down}{End}{LSHIFT Up}{LCTRL Down}{c}{LCTRL Up}{MouseClick,L,236,116,1,0,D}{MouseClick,L,54,116,1,0,U}{LCTRL Down}{LCTRL Up}{MouseClick,L,474,64,1,0,D}{MouseClick,L,474,64,1,0,U}{MouseClick,L,451,77,1,0,D}{MouseClick,L,451,77,1,0,U}{MouseClick,L,44,225,1,0,D}{MouseClick,L,44,225,1,0,U} OR playback={LCtrl}{F7} keydelay=10 windelay=100 movemouseafter=1 macro={WinActive}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{Down}{LCTRL Down}{Right}{Right}{LCTRL Up}{LSHIFT Down}{End}{LSHIFT Up}{LCTRL Down}{c}{LCTRL Up}{MouseClick,L,236,116,1,0,D}{MouseClick,L,54,116,1,0,U}{LCTRL Down}{LCTRL Up}{MouseClick,L,474,64,1,0,D}{MouseClick,L,474,64,1,0,U}{MouseClick,L,451,77,1,0,D}{MouseClick,L,451,77,1,0,U}{MouseClick,L,44,225,1,0,D}{MouseClick,L,44,225,1,0,U} Maybe add something like what is printed in bold here. I know the coding isnt right here, but i think this is the best way to describe what I am looking for. Anybody?

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  • PHP import functions

    - by ninuhadida
    Hi, I'm trying to find the best pragmatic approach to import functions on the fly... let me explain. Say I have a directory called functions which has these files: array_select.func.php stat_mediam.func.php stat_mean.func.php ..... I would like to: load each individual file (which has a function defined inside) and use it just like an internal php function.. such as array_pop(), array_shift(), etc. Once I stumbled on a tutorial (which I can't find again now) that compiled user defined functions as part of a PHP installation.. Although that's not a very good solution because on shared/reseller hosting you can't recompile the PHP installation. I don't want to have conflicts with future versions of PHP / other extensions, i.e. if a function named X by me, is suddenly part of the internal php functions (even though it might not have the same functionality per se) I don't want PHP to throw a fatal error because of this and fail miserably. So the best method that I can think of is to check if a function is defined, using function_exists(), if so throw a notice so that it's easy to track in the log files, otherwise define the function. However that will probably translate to having a lot of include/require statement in other files where I need such a function, which I don't really like. Or possibly, read the directory and loop over each *.func.php file and include_once. Though I find this a bit ugly. The question is, have you ever stumbled upon some source code which handled such a case? How was it implemented? Did you ever do something similar? I need as much ideas as possible! :)

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