Search Results

Search found 5807 results on 233 pages for 'generic'.

Page 190/233 | < Previous Page | 186 187 188 189 190 191 192 193 194 195 196 197  | Next Page >

  • getting a "default" concrete class that implements an interface

    - by Roger Joys
    I am implementing a custom (and generic) Json.net serializer and hit a bump in the road that I could use some help on. When the deserializer is mapping to a property that is an interface, how can I best determine what sort of object to construct to deserialize to to place into the interface property. I have the following: [JsonConverter(typeof(MyCustomSerializer<foo>))] class foo { int Int1 { get; set; } IList<string> StringList {get; set; } } My serializer properly serializes this object, and but when it comes back in, and I try to map the json parts to to object, I have a JArray and an interface. I am currently instantiating anything enumerable like List as theList = Activator.CreateInstance(property.PropertyType); This works create to work with in the deserialization process, but when the property is IList, I get runtime complaints (obviously) about not being able to instantiate an interface. So how would I know what type of concrete class to create in a case like this? Thank you

    Read the article

  • Alternatives to static methods on interfaces for enforcing consistency

    - by jayshao
    In Java, I'd like to be able to define marker interfaces, that forced implementations to provide static methods. For example, for simple text-serialization/deserialization I'd like to be able to define an interface that looked something like this: public interface TextTransformable<T>{ public static T fromText(String text); public String toText(); Since interfaces in Java can't contain static methods though (as noted in a number of other posts/threads: here, here, and here this code doesn't work. What I'm looking for however is some reasonable paradigm to express the same intent, namely symmetric methods, one of which is static, and enforced by the compiler. Right now the best we can come up with is some kind of static factory object or generic factory, neither of which is really satisfactory. Note: in our case our primary use-case is we have many, many "value-object" types - enums, or other objects that have a limited number of values, typically carry no state beyond their value, and which we parse/de-parse thousands of time a second, so actually do care about reusing instances (like Float, Integer, etc.) and its impact on memory consumption/g.c. Any thoughts?

    Read the article

  • NHibernate + Fluent long startup time

    - by PaRa
    Hi all, am new to NHibernate. When performing below test took 11.2 seconds (debug mode) i am seeing this large startup time in all my tests (basically creating the first session takes a tone of time) setup = Windows 2003 SP2 / Oracle10gR2 latest CPU / ODP.net 2.111.7.20 / FNH 1.0.0.636 / NHibernate 2.1.2.4000 / NUnit 2.5.2.9222 / VS2008 SP1 using System; using System.Collections; using System.Data; using System.Globalization; using System.IO; using System.Text; using System.Data; using NUnit.Framework; using System.Collections.Generic; using System.Data.Common; using NHibernate; using log4net.Config; using System.Configuration; using FluentNHibernate; [Test()] public void GetEmailById() { Email result; using (EmailRepository repository = new EmailRepository()) { results = repository.GetById(1111); } Assert.IsTrue(results != null); } public class EmailRepository : RepositoryBase { public EmailRepository():base() { } } In my RepositoryBase public T GetById(object id) { using (var session = sessionFactory.OpenSession()) using (var transaction = session.BeginTransaction()) { try { T returnVal = session.Get(id); transaction.Commit(); return returnVal; } catch (HibernateException ex) { // Logging here transaction.Rollback(); return null; } } } The query time is very small. The resulting entity is really small. Subsequent queries are fine. Its seems to be getting the first session started. Has anyone else seen something similar?

    Read the article

  • Upcasting without any added data fields.

    - by Benjamin Manns
    In my project I have a generic Packet class. I would like to be able to upcast to other classes (like LoginPacket or MovePacket). The base class contains a command and arguments (greatly simplified): public class Packet { public String Command; public String[] Arguments; } I would like to have be able to convert from Packet to LoginPacket (or any other) based on a check if Packet.Command == "LOGIN". The login packet would not contain any new data members, but only methods for accessing specific arguments. For example: public class LoginPacket : Packet { public String Username { get { return Arguments[0]; } set { Arguments[0] == value; } } public String Password { get { return Arguments[1]; } set { Arguments[1] == value; } } } It would be great if I could run a simple code that would cast from Packet to LoginPacket with something like LoginPacket _Login = (LoginPacket)_Packet;, but that throws a System.InvalidCastException. It seems like this would be an easy task, as no new data is included, but I can't figure out any other way than copying everything from the Packet class to a new LoginPacket class.

    Read the article

  • How do i select all text nodes using XSL?

    - by user323719
    I want to get the generate-id(.) of all the text nodes after node and before node . I am looking for some generic XSL and not tightly coupled to the sample input pattern mentioned below. For any input pattern i want to get the ids of all the text nodes between node and . Sample input for better understanding: <a> <b> <c> This is first text node </c> </b> <d> <e> This is my second text node </e> <f> This is my <m/>third text node </f> <g> One more text node </g> <h> <i> This is my fourth text node </i> </h> <j> This is my fifth <n/>text node </j> <k> <l> This is my sixth text node </l> </k> </d> </a> Expected output: Generate id of the text nodes with values "third text node ", "One more text node", "This is my fourth text node", "This is my fifth" which lie inbetween nodes <m/> and <n/> Please give your ideas.

    Read the article

  • Call .NET Webservice with Android

    - by Lasse P
    Hi, I know this question has been asked here before, but I don't think those answers were adequate for my needs. We have a SOAP webservice that is used for an iPhone application, but it is possible that we need an Android specific version or a proxy of the service, so we have the option to go with either SOAP or JSON. I have a few concerns about both methods: SOAP solution: Is it possible to generate java source code from a WSDL file, if so, will it include some kind of proxy class to invoke the webservice and will it work in the Android environment at all? Google has not provided any SOAP library in Android, so i need to use 3rd party, any suggestion? What about the performance/overhead with parsing and transmitting SOAP xml over the wire versus the JSON solution? JSON solution: There is a few classes in the Android sdk that will let me parse JSON, but does it support generic parsing, like if I want the result to be parsed as a complex type? Or would I need to implement that myself? I have read about 2 libraries before here on Stackoverflow, GSON an Jackson. What is the difference performance and usability (from a developers perspective) wise? Do you guys have any experince with either of those libraries? So i guess the big question is, what method to go with? I hope you can help me out. Thanks in advance :-)

    Read the article

  • Specifying different initial values for fields in inherited models (django)

    - by Shawn Chin
    Question : What is the recommended way to specify an initial value for fields if one uses model inheritance and each child model needs to have different default values when rendering a ModelForm? Take for example the following models where CompileCommand and TestCommand both need different initial values when rendered as ModelForm. # ------ models.py class ShellCommand(models.Model): command = models.Charfield(_("command"), max_length=100) arguments = models.Charfield(_("arguments"), max_length=100) class CompileCommand(ShellCommand): # ... default command should be "make" class TestCommand(ShellCommand): # ... default: command = "make", arguments = "test" I am aware that one can used the initial={...} argument when instantiating the form, however I would rather store the initial values within the context of the model (or at least within the associated ModelForm). My current approach What I'm doing at the moment is storing an initial value dict within Meta, and checking for it in my views. # ----- forms.py class CompileCommandForm(forms.ModelForm): class Meta: model = CompileCommand initial_values = {"command":"make"} class TestCommandForm(forms.ModelForm): class Meta: model = TestCommand initial_values = {"command":"make", "arguments":"test"} # ------ in views FORM_LOOKUP = { "compile": CompileCommandFomr, "test": TestCommandForm } CmdForm = FORM_LOOKUP.get(command_type, None) # ... initial = getattr(CmdForm, "initial_values", {}) form = CmdForm(initial=initial) This feels too much like a hack. I am eager for a more generic / better way to achieve this. Suggestions appreciated. Other attempts I have toyed around with overriding the constructor for the submodels: class CompileCommand(ShellCommand): def __init__(self, *args, **kwargs): kwargs.setdefault('command', "make") super(CompileCommand, self).__init__(*args, **kwargs) and this works when I try to create an object from the shell: >>> c = CompileCommand(name="xyz") >>> c.save() <CompileCommand: 123> >>> c.command 'make' However, this does not set the default value when the associated ModelForm is rendered, which unfortunately is what I'm trying to achieve. Update 2 (looks promising) I now have the following in forms.py which allow me to set Meta.default_initial_values without needing extra code in views. class ModelFormWithDefaults(forms.ModelForm): def __init__(self, *args, **kwargs): if hasattr(self.Meta, "default_initial_values"): kwargs.setdefault("initial", self.Meta.default_initial_values) super(ModelFormWithDefaults, self).__init__(*args, **kwargs) class TestCommandForm(ModelFormWithDefaults): class Meta: model = TestCommand default_initial_values = {"command":"make", "arguments":"test"}

    Read the article

  • Some images fails to load on Windows Server 2008

    - by Guffa
    I have an application running on a Windows Server 2008, that is processing uploaded images. Currently it successfully processes about 8000 images per day, creating 11 different sizes of each image. The problem that I have is that sometimes the application fails to load some images, I get the error "System.Runtime.InteropServices.ExternalException: A generic error occurred in GDI+.". The upload only accepts files with a JPEG extension (jpg/jpeg/jpe) or with a JPEG MIME type, and from what I can tell those images are really JPEG images. If I look at the image file in windows explorer on the server, it can successfully extract the thumbnail from the file, but if I try to open it, I get the error message "This is not a valid bitmap file, or it's format is not currently supported." from Paint. If I copy the image to my own computer, running Windows 7, there is no problem opening the image. It works in Paint, Windows Photo Viewer, Adobe Bridge, and Photoshop. If I try to load the image using Image.FromStream the same way as in the application running on the server, it loads just fine. (I have copied the file back to the server, and it still doesn't work, so there is nothing in the copying process that changes it.) When I look at the image information in Bridge, I see that the images are created using Picasa 3.0, but other than that I can't see anything special about them. I haven't yet found anyone having the same problem, or any known problems like this with the Picasa application. Has anyone had any similar problem, or know if there is something special about images created using Picasa? Is there any image codec that needs installing on the server to handle all kinds of JPEG images?

    Read the article

  • How do I access Dictionary items?

    - by salvationishere
    I am developing a C# VS2008 / SQL Server website app and am new to the Dictionary class. Can you please advise on best method of accomplishing this? Here is a code snippet: SqlConnection conn2 = new SqlConnection(connString); SqlCommand cmd = conn2.CreateCommand(); cmd.CommandText = "dbo.AppendDataCT"; cmd.CommandType = CommandType.StoredProcedure; cmd.Connection = conn2; SqlParameter p1, p2, p3; foreach (string s in dt.Rows[1].ItemArray) { DataRow dr = dt.Rows[1]; // second row p1 = cmd.Parameters.AddWithValue((string)dic[0], (string)dr[0]); p1.SqlDbType = SqlDbType.VarChar; p2 = cmd.Parameters.AddWithValue((string)dic[1], (string)dr[1]); p2.SqlDbType = SqlDbType.VarChar; p3 = cmd.Parameters.AddWithValue((string)dic[2], (string)dr[2]); p3.SqlDbType = SqlDbType.VarChar; } but this is giving me compiler error: The best overloaded method match for 'System.Collections.Generic.Dictionary<string,string>.this[string]' has some invalid arguments I just want to access each value from "dic" and load into these SQL parameters. How do I do this? Do I have to enter the key? The keys are named "col1", "col2", etc., so not the most user-friendly. Any other tips? Thanks!

    Read the article

  • ASP.NET how can access public properties of MasterPage from external Class ?

    - by eugeneK
    Why i can't access MasterPage's public property (MessagePlaceholder) from other Class (Errors) ? my master page code behind using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; public partial class MyMasterPage : System.Web.UI.MasterPage { public string MessagePlaceholder { get { return messagePlaceholder.InnerHtml; } set { messagePlaceholder.InnerHtml = value; } } protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { messagePlaceholder.InnerHtml = Errors.getMessage(); } } } my Errors Class public static string getMessage() { HttpContext c = HttpContext.Current; string messageType = ""; if (c.Session["errorMessage"] != null) { messageType = "errorMessage"; } else if (c.Session["successMessage"] != null) { messageType = "successMessage"; } if (!string.IsNullOrEmpty(messageType)) { StringBuilder userMessageSb = new StringBuilder(); userMessageSb.Append(string.Format("<div id=\"{0}\" title=\"{1}\">{2}</div>", messageType, messageType.Replace("Message",string.Empty), c.Session[messageType])); // fix so message will not re-appear c.Session.Remove(messageType); messageType = userMessageSb.ToString(); } return messageType; } public static void setSuccess(string successMessage, bool isRedirect) { HttpContext.Current.Session["successMessage"] = successMessage; } public static void setError(string errorMessage, bool isRedirect) { HttpContext.Current.Session["errorMessage"] = errorMessage; if (!isRedirect) { ((HttpContext.Current.CurrentHandler as System.Web.UI.Page).Master as MyMasterPage).MessagePlaceholder = getMessage(); } } this is how i set error if (true) { Errors.setError("this is an error demo", false); return; } or with redirect after error if (true) { Errors.setError("yet another error", true); Response.Redirect("~/error.aspx"); }

    Read the article

  • C# Interop.Word Adding an Image from project resource folder

    - by iamnobody
    Hi guys. Having some image problem with Interop.Word and C#. I want to add an image in the header of the document that I am going to generate. I have this code working perfectly section.Headers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Shapes.AddPicture(@"C:\Logo.jpg", ref x, ref x, ref x, ref x, ref x, ref x, ref x); Problem is that I can't have "C:\Logo.jpg" in the code since after publishing the project, there would most probably be no Logo.jpg in the C folder of the user. The image is already in my project's resource folder. I've used Image.FromFile("Logo.jpg") before but .AddPicture requires a string and not an image. Any ideas? Any help would be greatly appreciated. Thanks! -- edit -- Saw this over the net: string anyPath = @"C:\logo.jpg"; Properties.Resources.logo.Save(anyPath); section.Headers.[...].Shapes.AddPicture(anyPath, ... but then I still get a generic error in GDI+ or ExternalException was unhandled.

    Read the article

  • OOP C# Question: Making a Fruit a Pear

    - by Adam Kane
    Given that I have an instance of Fruit with some properties set, and I want to get those properties into a new Pear instance (because this particular Fruit happens to have the qualities of a pear), what's the best way to achieve this effect? For example, what we can't do is simple cast a Fruit to a Pear, because not all Fruits are Pears: public static class PearGenerator { public static Pear CreatePear () { // Make a new generic fruit. Fruit genericFruit = new Fruit(); // Upcast it to a pear. (Throws exception: Can't cast a Fruit to a Pear.) Pear pear = (Pear)genericFruit; // Return freshly grown pear. return ( pear ); } } public class Fruit { // some code } public class Pear : Fruit { public void PutInPie () { // some code } } Thanks! Update: I don't control the "new Fruit()" code. My starting point is that I've got a Fruit to work with. I need to get that Fruit into a new Pear somehow. Maybe copy all the properties one by one?

    Read the article

  • ASP.NET enum dropdownlist validation

    - by Arun Kumar
    I have got a enum public enum TypeDesc { [Description("Please Specify")] PleaseSpecify, Auckland, Wellington, [Description("Palmerston North")] PalmerstonNorth, Christchurch } I am binding this enum to drop down list using the following code on page_Load protected void Page_Load(object sender, EventArgs e) { if (TypeDropDownList.Items.Count == 0) { foreach (TypeDesc newPatient in EnumToDropDown.EnumToList<TypeDesc>()) { TypeDropDownList.Items.Add(EnumToDropDown.GetEnumDescription(newPatient)); } } } public static string GetEnumDescription(Enum value) { FieldInfo fi = value.GetType().GetField(value.ToString()); DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false); if (attributes != null && attributes.Length > 0) return attributes[0].Description; else return value.ToString(); } public static IEnumerable<T> EnumToList<T>() { Type enumType = typeof(T); // Can't use generic type constraints on value types, // so have to do check like this if (enumType.BaseType != typeof(Enum)) throw new ArgumentException("T must be of type System.Enum"); Array enumValArray = Enum.GetValues(enumType); List<T> enumValList = new List<T>(enumValArray.Length); foreach (int val in enumValArray) { enumValList.Add((T)Enum.Parse(enumType, val.ToString())); } return enumValList; } and my aspx page use the following code to validate <asp:DropDownList ID="TypeDropDownList" runat="server" > </asp:DropDownList> <asp:RequiredFieldValidator ID="TypeRequiredValidator" runat="server" ControlToValidate="TypeDropDownList" ErrorMessage="Please Select a City" Text="<img src='Styles/images/Exclamation.gif' />" ValidationGroup="city"></asp:RequiredFieldValidator> But my validation is accepting "Please Specify" as city name. I want to stop user to submit if the city is not selected.

    Read the article

  • Getting the time interval between typing characters in a TextBox, in C#

    - by sama
    I have a form that has a TextBox and a Label and I want to get the time of the first character entered in the textbox. Then if the user enters more than ten charcaters, the time between the first charcter entered and the tenth charcter entered is displayed in the label. Can any one help me please? I'm using C# Here is the code but I cannot complete it and I have many things that need to be written but I don't know how to continue. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Threading; namespace n { public partial class Form1 : Form { int count=0; public Form1() { InitializeComponent(); } private void textBox1_TextChanged(object sender, EventArgs e) { DateTime t1 = new DateTime();// the time when entering the first charcter DateTime t2 = new DateTime(); t2 = System.DateTime.Now - t1; int index = textBox1.SelectionStart; Point p; p = textBox1.GetPositionFromCharIndex(index); Thread t = new Thread(counttext); t.Start(); label1.Text = "t2"; } private int counttext() { while (textBox1.Text.Length < 10) { count++; if (count == 10) return count; } } } }

    Read the article

  • c# - what approach can I use to extend a group of classes that include implemented methods? (see des

    - by Greg
    Hi, I want to create an extendible package I am writing that has Topology, Node & Relationship classes. The idea is these base classes would have the various methods in them necessary to base graph traversal methods etc. I would then like to be able to reuse this by extending the package. For example the base requirements might see Relationship with a parentNode & childNode. Topology would have a List of Nodes and List of Relationships. Topology would have methods like FindChildren(int depth). Then the usage would be to extend these such that additional attributes for Node and Relationships could be added etc. QUESTION - What would be the best approach to package & expose the base level classes/methods? (it's kind of like a custom collection but with multiple facets). Would the following concepts come into play: Interfaces - would this be a good idea to have ITopology, INode etc, or is this not required as the user would extend these classes anyway? Abstract Classes - would the base classes be abstract classes Custom Generic Collection - would some approach using this concept assist (but how would this work if there are the 3 different classes) thanks

    Read the article

  • How to convert Big Endian and how to flip the highest bit?

    - by Robert Frank
    I am using a TStream to read binary data (thanks to this post: http://stackoverflow.com/questions/2878180/how-to-use-a-tfilestream-to-read-2d-matrices-into-dynamic-array). My next problem is that the data is Big Endian. From my reading, the Swap() method is seemingly deprecated. How would I swap the types below? 16-bit two's complement binary integer 32-bit two's complement binary integer 64-bit two's complement binary integer IEEE single precision floating-point - Are IEEE affected by Big Endian? And, finally, since the data is unsigned, the creators of this dataset have stored the unsigned values as signed integers (excluding the IEEE). They instruct that one need only add an offset (2^15, 2^31, and 2^63) to recover the unsigned data. But, they note that flipping the most significant bit is the fastest way to do that. How does one efficiently flip the most significant bit of a 16, 32, or 64-bit integer? So, if the data on disk (16-bit) is "85 FB" - the desired result after reading the data and swapping and bit flipping would be 1531. Is there a way to accomplish the swapping and bit flipping with generics so it fits into the generic answer at the link above? Yes, kids, THIS is how scientific astronomical data is stored by NASA, ESO, and all professional astronomers. This FITS standard is considered by some to be one of the most successful standards ever created in its proliferation and flexibility!

    Read the article

  • XSLT 1.0: restrict entries in a nodeset

    - by Mike
    Hi, Being relatively new to XSLT I have what I hope is a simple question. I have some flat XML files, which can be pretty big (eg. 7MB) that I need to make 'more hierarchical'. For example, the flat XML might look like this: <D0011> .... .... and it should end up looking like this: <D0011> .... .... I have a working XSLT for this, and it essentially gets a nodeset of all the b elements and then uses the 'following-sibling' axis to get a nodeset of the nodes following the current b node (ie. following-sibling::*[position() =$nodePos]). Then recursion is used to add the siblings into the result tree until another b element is found (I have parameterised it of course, to make it more generic). I also have a solution that just sends the position in the XML of the next b node and selects the nodes after that one after the other (using recursion) via a *[position() = $nodePos] selection. The problem is that the time to execute the transformation increases unacceptably with the size of the XML file. Looking into it with XML Spy it seems that it is the 'following-sibling' and 'position()=' that take the time in the two respective methods. What I really need is a way of restricting the number of nodes in the above selections, so fewer comparisons are performed: every time the position is tested, every node in the nodeset is tested to see if its position is the right one. Is there a way to do that ? Any other suggestions ? Thanks, Mike

    Read the article

  • Inheritance and type parameters of Traversable

    - by Jesper
    I'm studying the source code of the Scala 2.8 collection classes. I have questions about the hierarchy of scala.collection.Traversable. Look at the following declarations: package scala.collection trait Traversable[+A] extends TraversableLike[A, Traversable[A]] with GenericTraversableTemplate[A, Traversable] trait TraversableLike[+A, +Repr] extends HasNewBuilder[A, Repr] with TraversableOnce[A] package scala.collection.generic trait HasNewBuilder[+A, +Repr] trait GenericTraversableTemplate[+A, +CC[X] <: Traversable[X]] extends HasNewBuilder[A, CC[A] @uncheckedVariance] Question: Why does Traversable extend GenericTraversableTemplate with type parameters [A, Traversable] - why not [A, Traversable[A]]? I tried some experimenting with a small program with the same structure and got a strange error message when I tried to change it to Traversable[A]: error: Traversable[A] takes no type parameters, expected: one I guess that the use of the @uncheckedVariance annotation in GenericTraversableTemplate also has to do with this? (That seems like a kind of potentially unsafe hack to force things to work...). Question: When you look at the hierarchy, you see that Traversable inherits HasNewBuilder twice (once via TraversableLike and once via GenericTraversableTemplate), but with slightly different type parameters. How does this work exactly? Why don't the different type parameters cause an error?

    Read the article

  • What are some commonly used source code check-in policies?

    - by rwmnau
    I'm curious what code review policies other development shops apply to their source code when it's checked into the source control repository. I'm setting up a TFS (Team Foundation) server, and I'd like to apply some check-in policies to start to stamp out bad practices. For example, I was thinking of starting with the following couple, so this is the kind of stuff I'm looking for: Prohibit empty "Catch" blocks. This would prevent applications from swallowing any exceptions without at least requiring a comment explaining why it's not necessary to do anything with the exception. Prohibit "Catch ex as Exception" generic exception handling. Instead, require code to catch specific types of exceptions and deal with them appropriately, instead of just building catch-all handling. Require a check-in comment. This one should be self-explanatory, though it seems that TFS (and most other source-control systems) don't require a comment by default. While these are just examples, they're where I'm thinking of starting, and while I'd like some additional examples of what's popular, I'm open to feedback on these. Also, though we're a mostly .NET shop, I imagine the popular policies are universal across languages and IDEs (we have some Java development and a few people who will use the repository develop with Eclipse).

    Read the article

  • Object Design catalog and resources

    - by Tauren
    I'm looking for web sites, books, or other resources that provide a catalog of object designs used in common scenarios. I'm not looking for generic design patterns, but for samples of actual object designs that were used to solve real problems. For instance, I'm about to build an internal messaging system for a web application, similar to Facebook's messaging system. This system will allow administrators to send messages to all members, to selected groups of members, or to individuals. Members can send messages to other members or groups of members. Fairly common stuff and a feature that I'm sure thousands of web applications require. I know each situation is different and there are a million ways to design this solution. Although this scenario isn't really all that complex, I'm sure the basic design of the necessary objects and relationships for a system like this has already been done many times. It would be nice to review other similar designs before building my own. Is there a place where people can share their designs and others can browse/search through the catalog to review and provide feedback on them? StackOverflow could be used to a degree for this, but doesn't really provide a catalog of designs. Any other resources that would relate?

    Read the article

  • Finding What You Need in R: function arguments/parameters from outside the function's package

    - by doug
    Often in R, there are a dozen functions scattered across as many packages--all of which have the same purpose but of course differ in accuracy, performance, theoretical rigor, and so on. How do you gather all of these in one place before you start your task? So for instance: the generic plot function. Setting secondary ticks is much easier (IMHO) using a function outside of the base package, minor.tick(nx=n, ny=n, tick.ratio=n), found in Hmisc. Of course, that doesn't show up in plot's docstring. Likewise, the data-input arguments to 'plot' can be supplied by an object returned from the function 'hexbin', again, from a library outside of the base installation (where 'plot' resides). What would be great obviously is a programmatic way to gather these function arguments from the various libraries and put them in a single namespace. edit: (trying to re-state my example just above more clearly:) the arguments to plot supplied in the base package for, e.g., setting the axis tick frequency are xaxp/yaxp; however, one can also set a/t/f via a function outside of the base package, again, as in the minor.tick function from the Hmisc package--but you wouldn't know that just from looking at the plot method signature. Is there a meta function in R for this? So far, as i come across them, i've been manually gathering them in a TextMate 'snippet' (along with the attendant library imports). This isn't that difficult or time consuming, but i can only update my snippet as i find out about these additional arguments/parameters. Is there a canonical R way to do this, or at least an easier way? Just in case that wasn't clear, i am not talking about the case where multiple packages provide functions directed to the same statistic or view (e.g., 'boxplot' in the base package; 'boxplot.matrix' in gplots; and 'bplots' in Rlab). What i am talking is the case in which the function name is the same across two or more packages.

    Read the article

  • Does F# documentation have a way to search for functions by their types?

    - by Nathan Sanders
    Say I want to know if F# has a library function of type ('T -> bool) -> 'T list -> int ie, something that counts how many items of a list that a function returns true for. (or returns the index of the first item that returns true) I used to use the big list at the MSR site for F# before the documentation on MSDN was ready. I could just search the page for the above text because the types were listed. But now the MSDN documentation only lists types on the individual pages--the module page is a mush of descriptive text. Google kinda-sorta works, but it can't help with // compatible interfaces ('T -> bool) -> Seq<'T> -> int // argument-swaps Seq<'T> -> ('T -> bool) -> int // type-variable names ('a -> bool) -> Seq<'a> -> int // wrappers ('a -> bool) -> 'a list -> option<int> // uncurried versions ('T -> bool) * 'T list -> int // .NET generic syntax ('T -> bool) -> List<'T> -> int // methods List<'T> member : ('T -> bool) -> int Haskell has a standalone program for this called Hoogle. Does F# have an equivalent, like Fing or something?

    Read the article

  • What do I name classes whose only purpose is to act as a structure?

    - by Sergio Tapia
    For example, take my Actor class: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Drawing; namespace FreeIMDB { class Actor { public string Name { get; set; } public Image Portrait { get; set; } public DateTime DateOfBirth { get; set; } public List<string> ActingRoles { get; set; } public List<string> WritingRoles { get; set; } public List<string> ProducingRoles { get; set; } public List<string> DirectingRoles { get; set; } } } This class will only be used to stuff information into it, and allow other developers to get their values. What are these types of classes officially called? What is the correct nomenclature?

    Read the article

  • How to parse time stamps with Unicode characters in Java or Perl?

    - by ram
    I'm trying to make my code as generic as possible. I'm trying to parse install time of a product installation. I will have two files in the product, one that has time stamp I need to parse and other file tells the language of the installation. This is how I'm parsing the timestamp public class ts { public static void main (String[] args){ String installTime = "2009/11/26 \u4e0b\u5348 04:40:54"; //This timestamp I got from the first file. Those unicode charecters are some Chinese charecters...AM/PM I guess //Locale = new Locale();//don't set the language yet SimpleDateFormat df = (SimpleDateFormat)DateFormat.getDateTimeInstance(DateFormat.DEFAULT,DateFormat.DEFAULT); Date instTime = null; try { instTime = df.parse(installTime); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println(instTime.toString()); } } The output I get is Parsing Failed java.text.ParseException: Unparseable date: "2009/11/26 \u4e0b\u5348 04:40:54" at java.text.DateFormat.parse(Unknown Source) at ts.main(ts.java:39) Exception in thread "main" java.lang.NullPointerException at ts.main(ts.java:45) It throws exception and at the end when I print it, it shows some proper date... wrong though. I would really appreciate if you could clarify me on these doubts How to parse timestamps that have unicode characters if this is not the proper way? If parsing is failed, how could instTime able to hold some date, wrong though? I know its some chinese,Korean time stamps so I set the locale to zh and ko as follows.. even then same error comes again Locale = new Locale("ko"); Locale = new Locale("ja"); Locale = new Locale("zh"); How can I do the same thing in Perl? I can't use Date::Manip package; Is there any other way?

    Read the article

  • How to find nearest week day for an arbitrary date?

    - by Stig Brautaset
    Is there a more elegant way than the below to find the nearest day of the week for a given date using JodaTime? I initially thought setCopy() would be it, but this sets the day to the particular day in the same week. Thus, if ld is 2011-11-27 and day is "Monday" the following function returns 2011-11-21, and not 2011-11-28 as I want. // Note that "day" can be _any_ day of the week, not just weekdays. LocalDate getNearestDayOfWeek(LocalDate ld, String day) { return ld.dayOfWeek().setCopy(day); } Below is a work-around I came up with that works for the particular constraints in my current situation, but I'd love to get help find a completely generic solution that works always. LocalDate getNearestDayOfWeek(LocalDate ld, String day) { LocalDate target = ld.dayOfWeek().setCopy(day); if (ld.getDayOfWeek() > DateTimeConstants.SATURDAY) { target = target.plusWeeks(1); } return target; } Looking more into this I came up with this, which seems to be a more correct solution, though it seems awfully complicated: LocalDate getNearestDayOfWeek(LocalDate ld, String day) { LocalDate target = ld.dayOfWeek().setCopy(day); if (target.isBefore(ld)) { LocalDate nextTarget = target.plusWeeks(1); Duration sincePrevious = new Duration(target.toDateMidnight(), ld.toDateMidnight()); Duration untilNext = new Duration(ld.toDateMidnight(), nextTarget.toDateMidnight()); if (sincePrevious.isLongerThan(untilNext)) { target = nextTarget; } } return target; }

    Read the article

< Previous Page | 186 187 188 189 190 191 192 193 194 195 196 197  | Next Page >