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• String labels on boxplot outliers

  - by Benoît Collette

  Hi! I want to put string labels on outliers in a boxplot. Here's a simplification of the dataset I'm using: [,x] [,y] [,z] 7 2 a 10 2 b 112 3 c boxdata<-boxplot(x ~ y) To put values as label on outliers by group, I use this function: for(i in 1:length(boxdata$group)){ text(boxdata$group[i], boxdata$out[i], which(x==boxdata$out[i]),labels=boxdata$out[i],pos=4) } The problem is that I want to put z (string) as label instead of outlier value, but I don't know how to proceed. What do I need to do? Thank you! Ben

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• Use of Java constructors in persistent entities

  - by Mr Morgan

  Hello I'm new to JPA and using persistence in Java anyway and I have two questions I can't quite work out: I have generated tags as: @JoinColumn(name = "UserName", referencedColumnName = "UserName") @ManyToOne(optional = false) private User userName; @JoinColumn(name = "DatasetNo", referencedColumnName = "DatasetNo") @ManyToOne(optional = false) private Dataset datasetNo; But in one of the constructors for the class, no reference is made to columns UserName or DatasetNo whereas all other columns in the class are referenced in the constructor. Can anyone tell me why this is? Both columns UserName and DatasetNo are 'foreign keys' on the entity Visualisation which corresponds to a database table of the same name. I can't quite work out the ORM. And when using entity classes, or POJO, is it better to have class variables like: private User userName; Where an instance of a class is specified or simply the key of that class instance like: private String userName; Thanks Mr Morgan.

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• Click edit button twice in gridview asp.net c# issue

  - by Supriyo Banerjee

  I have a gridview created on a page where I want to provide an edit button for the user to click in. However the issue is the grid view row becomes editable only while clicking the edit button second time. Not sure what is going wrong here, any help would be appreciated. One additional point is my grid view is displayed on the page only on a click of a button and is not there on page_load event hence. Posting the code snippets: //MY Aspx code <Columns> <asp:TemplateField HeaderText="Slice" SortExpression="name"> <ItemTemplate> <asp:Label ID="lblslice" Text='<%# Eval("slice") %>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblslice" Text='<%# Eval("slice") %>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Metric" SortExpression="Description"> <ItemTemplate> <asp:Label ID="lblmetric" Text='<%# Eval("metric")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblmetric" Text='<%# Eval("metric")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Original" SortExpression="Type"> <ItemTemplate> <asp:Label ID="lbloriginal" Text='<%# Eval("Original")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lbloriginal" Text='<%# Eval("Original")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="WOW" SortExpression="Market"> <ItemTemplate> <asp:Label ID="lblwow" Text='<%# Eval("WOW")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:Label ID="lblwow" Text='<%# Eval("WOW")%>' runat="server"></asp:Label> </EditItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Change" SortExpression="Market" > <ItemTemplate> <asp:Label ID="lblChange" Text='<%# Eval("Change")%>' runat="server"></asp:Label> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="TxtCustomerID" Text='<%# Eval("Change") %> ' runat="server"></asp:TextBox> </EditItemTemplate> </asp:TemplateField> <asp:CommandField HeaderText="Edit" ShowEditButton="True" /> </Columns> </asp:GridView> //My code behind: protected void Page_Load(object sender, EventArgs e) { } public void populagridview1(string slice,string fromdate,string todate,string year) { SqlCommand cmd; SqlDataAdapter da; DataSet ds; cmd = new SqlCommand(); cmd.CommandType = CommandType.StoredProcedure; cmd.CommandText = "usp_geteventchanges"; cmd.Connection = conn; conn.Open(); SqlParameter param1 = new SqlParameter("@slice", slice); cmd.Parameters.Add(param1); SqlParameter param2 = new SqlParameter("@fromdate", fromdate); cmd.Parameters.Add(param2); SqlParameter param3 = new SqlParameter("@todate", todate); cmd.Parameters.Add(param3); SqlParameter param4 = new SqlParameter("@year", year); cmd.Parameters.Add(param4); da = new SqlDataAdapter(cmd); ds = new DataSet(); da.Fill(ds, "Table"); GridView1.DataSource = ds; GridView1.DataBind(); conn.Close(); } protected void ImpactCalc(object sender, EventArgs e) { populagridview1(ddl_slice.SelectedValue, dt_to_integer(Picker1.Text), dt_to_integer(Picker2.Text), Txt_Year.Text); } protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e) { gvEditIndex = e.NewEditIndex; Gridview1.DataBind(); } My page layout This edit screen appears after clicking edit twice.. the grid view gets displayed on hitting the Calculate impact button. The data is from a backend stored procedure which is fired on clicking the Calculate impact button

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• reading excell file in vb.net

  - by Mark

  can anyone help me on how to know EOF of excel using vb.net? i have this code but it crash when i try delete the proceeding rows from row 6 to downward. my problem is, my code was still reading a null values of rows that i deleted in excel.. this is my code: Dim xlsConn As New OleDbConnection Dim xlsAdapter As New OleDbDataAdapter Dim xlsDataSet As New DataSet xlsConn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & pathName & " ; Extended Properties=Excel 8.0") strSQL = "SELECT * FROM [Sheet1$]" xlsAdapter.SelectCommand = New OleDbCommand(strSQL, xlsConn) xlsDataSet.Clear() xlsAdapter.Fill(xlsDataSet) ListView1.Items.Clear() Dim listItem As ListViewItem For ctr As Integer = 0 To xlsDataSet.Tables(0).Rows.Count - 1 listItem = ListView1.Items.Add(xlsDataSet.Tables(0).Rows(ctr).Item("EmpNo").ToString) listItem.SubItems.Add(xlsDataSet.Tables(0).Rows(ctr).Item("EmpName").ToString) Next Can anyone help me to fix this bugs!

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• How to enable Automatic Sorting of IEnumerable Data in GridView?

  - by ace

  How can I enable automatic sorting of my BLL which returns a List CustomerList:List in a GridView? Customer is my own strongly typed class and CustomerList is a List of customers. I know one approach is to set the AllowSorting property to true in the GridView and handle the OnSorting event and call a sorting method defined in my CustomerList class. However I would like a solution which is automatic in the sense that I do not have to handle the OnSorting Event, it should be like how GridView handles automatic sorting for DataView, DataTable, and DataSet. Is there an Interface I need to implement on my CustomerList or Customer class that will enable that functionality?

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• how to convert Database Hierarchical Data to XML using ASP.net 3.5 and LINQ

  - by mahdiahmadirad

  hello guys! i have a table with hierarchical structure. like this: and table data shown here: this strategy gives me the ability to have unbounded categories and sub-categories. i use ASP.net 3.5 SP1 and LINQ and MSSQL Server2005. How to convert it to XML? I can Do it with Dataset Object and ".GetXML()" method. but how to implement it with LINQtoSQL or LINQtoXML??? or if there is another simpler way to perform that? what is your suggestion? the best way? I searched the web but found nothing for .net 3.5 featuers.

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• SQL - Counting sets of Field-B values for each Field-A value

  - by potrnd

  Hello, First of all sorry that I could not think of a more descriptive title. What I want to do is the following using only SQL: I have some lists of strings, list1, list2 and list3. I have a dataset that contains two interesting columns, A and B. Column A contains a TransactionID and column B contains an ItemID. Naturally, there can be multiple rows that share the same TransactionIDs. I need to catch those transactions that have at least one ItemID in each and every list (list1 AND list2 AND list3). I also need to count how many times does that happen for each transaction. [EDIT] That is, count how many full sets of ItemIDs there are for each TransactionID", "Full Set" being any element of the list1 with any element of the list2 with any element of the list3 I hope that makes enough sense, perhaps I will be able to explain it better with a clear head. Thanks in advance

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• XSD data set with Oracle database

  - by Ed Woodcock

  Hi folks, I'm having a major issue with an XSD dataset mapping thingy that I'm using within my current project. We are using XSDs for some data abstraction (it's quicker and debatably more maintainable that using Parameterised SQL or a StoredProc), and on my machine (running in the VS development environment) thy're working fine. However, on the Pre-production server we use for our testing, the XSDs are not working correctly: some method calls will fail with the following error: System.ArgumentException: Value does not fall within the expected range. at Oracle.DataAccess.Client.OracleParameter.set_DbType(DbType value) Has anyone ever encountered this issue before? The methods being called are simple select statements using 1-3 parameters, and as I said before they work fine on my machine.

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• In-memory Database in Excel

  - by user329174

  Hello, I am looking for a way to import a datatable from Access into an Excel variable and then run queries through this variable to speed up the process. I am trying to migrate from C# .NET where I read a data table from an access database into memory and then used LINQ to query this dataset. It is MUCH faster than how I have it currently coded in VBA where I must make lots of calls to the actual database, which is slow. I have seen the QueryTable mentioned, but it appears that this requires pasting the data into the excel sheet. I would like to keep everything in memory and minimize the interaction between the Excel Sheet and the VBA code as much as possible. I wish we didn't need to use Excel+VBA to do this, but we're kind of stuck with that for now. Thanks for the help!

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• Entity Framework associations killing performance

  - by Chris

  Here is the performance test i am looking at. I have 8 different entities that are table per type. Some of the entities contain over 100 thousand rows. This particular application does several recursive calculations on the client so I think it may be best to preload the data instead of lazy loading. If there are no associations I can load the entire database in about 3 seconds. As I add associations in any way the performance starts to drastically decline. I am loading all the data the same way (just calling toList() on the entity attached to the context). I ran the test with edmx generated classes and self tracking entities and had similar results. I am sure if I were to try and deal with the associations myself, similar to how I would in a dataset, the performance problem would go away. On the other hand I am pretty sure this is not how the entity framework was intended to being used. Any thoughts or ideas?

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• .net Studio Local Database

  - by testerwpf

  Hello everyone, i am designing a local database in .net with wpf as gui. I have added a new database, and added a new table. Through the TableAdapter i generated 2 statements ( 1 statement is a select stmt and 1 is a insert) , i insert name and firstname (id is auto generated). It works fine, i can display the table in a datagrid (wpf toolkit) and also add new items (name,firstname), when i close and start the application everything is fine (data in table is stored) BUT when i try to preview data in my database dataset (where my Adapters exist) , no data is displayed and then the table gets deleted.. why? public partial class MainWindow : Window { public MainWindow() { this.InitializeComponent(); PlayerTableAdapter objPlayerTableAdapter = new PlayerTableAdapter(); objDataGridResults.ItemsSource = objPlayerTableAdapter.GetDataAllPlayer(); } //Button Event onClick private void m_voidAddPlayer(object sender, System.Windows.RoutedEventArgs e) { PlayerTableAdapter objPlayerTableAdapter = new PlayerTableAdapter(); objPlayerTableAdapter.InsertQueryPlayer(objTextBoxPlayerName.Text.ToString(), objTextBoxPlayerFirstName.Text.ToString()); objDataGridResults.ItemsSource = objPlayerTableAdapter.GetDataAllPlayer(); } }

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• Windows Azure Table Storage LINQ Operators

  - by Ryan Elkins

  Currently Table Storage supports From, Where, Take, and First. Are there plans to support any of the other 29 operators? If we have to code for these ourselves, how much of a performance difference are we looking at to something similar via SQL and SQL Server? Do you see it being somewhat comparable or will it be far far slower if I need to do a Count or Sum or Group By over a gigantic dataset? I like the Azure platform and the idea of cloud based storage. I like Windows Azure for the amount of data it can store and the schema-less nature of table storage. SQL Azure just won't work due to the high cost to storage space.

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• asp.net datasource problem

  - by harold-sota

  I'm insert a dropdwon list in datagrid on row editing. wen i run the project the datasource is not rekognized <asp:TemplateField HeaderText="Lookup 1"> <EditItemTemplate> <asp:DropDownList ID="Loocup1DropDownList" Width="100%" runat="server" DataSource ="<%GetValueForDropDownCombinationContent()%>" DataValueField="LOOKUP_ID" DataTextField="lookup_name" > </asp:DropDownList> </EditItemTemplate> <ItemTemplate> <asp:Label ID="LOOKUP1_NAME" runat="server" Text='<%# Bind("LOOKUP1_NAME") %>'></asp:Label> </ItemTemplate> This is the vb.net function Protected Function GetValueForDropDownCombinationContent() As IDataSource Dim dsProductLookups As New DataSet dsProductLookups = DocumentManager.Data.DataRepository.Provider.ExecuteDataSet("sp_GetCombinationsLookups", productCombo.SelectedValue) Return dsProductLookups End Function any ideas???

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• free public databases with non-trivial table structures?

  - by Caffeine Coma

  I'm looking for some sample database data that I can use for testing and demonstrating a DB tool I am working on. I need a DB that has (preferably) many tables, and many foreign key relationships between the tables. Ideally the data would be in SQL dump format, or at least in something that maintains the foreign key references, and could be easily import into an RDBMS (MySQL or H2). The dataset itself doesn't have to be huge (in fact, best if it's not). I thought about using the Stackoverflow Data Dump, but it's only about 5 tables.

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• Hierarchical Data in MySQL is fast to retrieve?

  - by ajsie

  i've got a list of all countries - states - cities (- subcities/villages etc) in a XML file and to retrieve for example a state's all cities it's really quick with XML (using xml parser). i wonder, if i put all this information in mysql, is retrieving a state's all cities as fast as with XML? cause XML is designed to store hierarchical data while relational databases like mysql are not. the list contains like 500 000 entities. so i wonder if its as fast as XML using either of: Adjacency list model Nested Set model And which one should i use? Cause (theoretically) there could be unlimited levels under a state. And which is fastest for this huge dataset? Thanks!

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• Hierarchical Data in MySQL is as fast as XML to retrieve?

  - by ajsie

  i've got a list of all countries - states - cities (- subcities/villages etc) in a XML file and to retrieve for example a state's all cities it's really quick with XML (using xml parser). i wonder, if i put all this information in mysql, is retrieving a state's all cities as fast as with XML? cause XML is designed to store hierarchical data while relational databases like mysql are not. the list contains like 500 000 entities. so i wonder if its as fast as XML using either of: Adjacency list model Nested Set model And which one should i use? Cause (theoretically) there could be unlimited levels under a state (i heard that adjacency isn't good for unlimited child-levels). And which is fastest for this huge dataset? Thanks!

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• How do I create queries to SQL Server tables via Visual Studio when no knowledge about SQL nor Linq?

  - by Kent S. Clarkson

  Let´s be frank, my knowledge regarding SQL language is very low. Nevertheless, my boss gave me the task to build a database application using the following tools: SQL Server and Visual Studio 2008; C#. I use the VS DataSet as a local mirror of the SQL Server. And let´s be frank again, my understanding of the VS Query builder is also very small, I´m finding it quite confusing, actually. So no help to find from Query builder. And my knowledge of Linq is even lower... Perhaps I should mention that the deadline for the project is "aggressively" set, so I have no chance to learn enough about these things during the project. And I´m a bit stupid too, which is no help when it comes to challenges like this (on other occations it might be quite useful though) With these permissions, what should I do (except for killing myself or retire) to be able to query my tables in a sufficient way?

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• How to create Master/Detail view with two datagrids in ColdFusion

  - by Maklar

  In Coldfusion, I have Master and Detail data that I need to display in two separate cfgrids; like the typical Customers/Orders scenario. My cfgrids are bound to cfc functions which populate the cfgrids. In my current dataset, only one Customer has Orders and when I click on this record in the Master datagrid the Detail datagrid displays the related records. But when I click on a record in the Master datagrid that has no related detail records, the Detail datagrid does not refresh but maintains display of the previous data. Also the search icon within the datagrid's control panel indicates it is searching for values rather than displaying the Refresh icon. Can you please show me how to establish Master and Detail cfgrids where I can see Orders of Customers as I navigate through the Master datagrid? Any and all help will be greatly appreciated! Maklar

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• How to pass parameters to report model in Reporting Services

  - by savras

  I'm developing report in RS that show top N customers based on some criteria. It also allows to select number of customers and period of time. Is it possible to do it by using report model? Thing that it seems to be difficult is how to pass parameters determined by user. Another thing that in my oppinion is very disappointing is that i cannot use SQL query as dataset query, because it uses odd and elaborate XML. Although report model items seem to map its fields to query or table fields. I m concerning using report models because i need to provide uniform data model (the same tables and fields) for more or less different database schemas. It would be very nice if somebody would explain what can be done with report models and what can not.

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• Optimal Sharing of heavy computation job using Snow and/or multicore

  - by James

  Hi, I have the following problem. First my environment, I have two 24-CPU servers to work with and one big job (resampling a large dataset) to share among them. I've setup multicore and (a socket) Snow cluster on each. As a high-level interface I'm using foreach. What is the optimal sharing of the job? Should I setup a Snow cluster using CPUs from both machines and split the job that way (i.e. use doSNOW for the foreach loop). Or should I use the two servers separately and use multicore on each server (i.e. split the job in two chunks, run them on each server and then stich it back together). Basically what is an easy way to: 1. Keep communication between servers down (since this is probably the slowest bit). 2. Ensure that the random numbers generated in the servers are not highly correlated.

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• ASP.Net repeater item.DataItem is null

  - by mattgcon

  Within a webpage, upon loading, I fill a dataset with two table with a relation between those tables and then load the data into a repeater with a nested repeater. This can also occur after the user clicks on a button. The data gets loaded from a SQL database and the repeater datasource is set to the dataset after a postback. However, when ItemDataBound occurs the Item.Dataitem is always null. Why would this occur? below is my HTML repeater code <asp:Repeater ID="rptCustomSpaList" runat="server" onitemdatabound="rptCustomSpaList_ItemDataBound"> <HeaderTemplate> </HeaderTemplate> <ItemTemplate> <table> <tr> <td> <asp:Label ID="Label3" runat="server" Text="Spa Series:"></asp:Label> </td> <td> <asp:Label ID="Label4" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "SPASERIESVALUE") %>'></asp:Label> </td> </tr> <tr> <td> <asp:Label ID="Label5" runat="server" Text="Spa Model:"></asp:Label> </td> <td> <asp:Label ID="Label6" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "SPAMODELVALUE") %>'></asp:Label> </td> </tr> <tr> <td> <asp:Label ID="Label9" runat="server" Text="Acrylic Color:"></asp:Label> </td> <td> <asp:Label ID="Label10" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "ACRYLICCOLORVALUE") %>'></asp:Label> </td> </tr> <tr> <td> <asp:Label ID="Label11" runat="server" Text="Cabinet Color:"></asp:Label> </td> <td> <asp:Label ID="Label12" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "CABPANCOLORVALUE") %>'></asp:Label> </td> </tr> <tr> <td> <asp:Label ID="Label17" runat="server" Text="Cabinet Type:"></asp:Label> </td> <td> <asp:Label ID="Label18" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "CABINETVALUE") %>'></asp:Label> </td> </tr> <tr> <td> <asp:Label ID="Label13" runat="server" Text="Cover Color:"></asp:Label> </td> <td> <asp:Label ID="Label14" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "COVERCOLORVALUE") %>'></asp:Label> </td> </tr> </table> <asp:Label ID="Label15" runat="server" Text="Options:"></asp:Label> <asp:Repeater ID="rptCustomSpaItem" runat="server"> <HeaderTemplate> <table> </HeaderTemplate> <ItemTemplate> <tr> <td> <asp:Label ID="Label1" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "PROPERTY") %>'></asp:Label> </td> <td> <asp:Label ID="Label2" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "VALUE") %>'></asp:Label> </td> </tr> </ItemTemplate> <FooterTemplate> </table> </FooterTemplate> </asp:Repeater> <table> <tr> <td style="padding-top:15px;padding-bottom:30px;"> <asp:Label ID="Label7" runat="server" Text="Configured Price:"></asp:Label> </td> <td style="padding-top:15px;padding-bottom:30px;"> <asp:Label ID="Label8" runat="server" Text='<%#DataBinder.Eval(Container.DataItem, "SPAVALUEVALUE") %>'></asp:Label> </td> </tr> </table> <asp:Label ID="Label16" runat="server" Text="------"></asp:Label> </ItemTemplate> <FooterTemplate></FooterTemplate> </asp:Repeater>

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• Save BLOB to disk as Image C#

  - by TGuimond

  Hello, I am developing a web application that calls web services developed by a third party to send/receive data from a clients database. I am building the application using ASP.NET 3.5 C#. The way that they are providing me images is in BLOB format. I call their method and what I get back is a DataSet with 2 fields "logo_name" and "logo" which is the BLOB field. What I want to do is: Save the image locally on the disk (to minimize calls to their database in the future). I have been playing around with a couple of different ways of doing this but cannot seem to get the image to save correctly. I have been able to create a file in a folder with the correct name but if I try to view the image it does not work. I was hoping someone could give me some sample code to show me how to save a BLOB field to the local disk? Thanks

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• R ggplot barplot; Fill based on two separate variables

  - by user1476968

  A picture says more than a thousand words. As you can see, my fill is based on the variable variable. Within each bar there is however multiple data entities (black borders) since the discrete variable complexity make them unique. What I am trying to find is something that makes each section of the bar more distinguishable than the current look. Preferable would be if it was something like shading. Here's an example (not the same dataset, since the original was imported): dat <- read.table(text = "Complexity Method Sens Spec MMC 1 L Alpha 50 20 10 2 M Alpha 40 30 80 3 H Alpha 10 10 5 4 L Beta 70 50 60 5 M Beta 49 10 80 6 H Beta 90 17 48 7 L Gamma 19 5 93 8 M Gamma 18 39 4 9 H Gamma 10 84 74", sep = "", header=T) library(ggplot2) library(reshape) short.m <- melt(dat) ggplot(short.m, aes(x=Method, y= value/100 , fill=variable)) + geom_bar(stat="identity",position="dodge", colour="black") + coord_flip()

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• How to programmatically change a data cell of Ms Access using VB.Net?

  - by manuel

  I have a Microsoft Access database file connected to VB.NET. In the database table, I have a 'No.' and a 'Status' column. Then I have a textbox where I can input an integer. I also have a button, which will change the data cell in 'Status' where 'No.' = textbox.Text(), when I click it. Let's say I want the 'Status' cell to be changed to "Low". What codes should I put in the button_Click event handler? Here is the codes I used to retrieve and display the database table. Public Class theForm Dim con As New OleDb.OleDbConnection Dim ds As New DataSet Dim daTitles As OleDb.OleDbDataAdapter Private Sub theForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=|DataDirectory|\db1.mdb" con.Open() daTitles = New OleDb.OleDbDataAdapter("SELECT * FROM Titles", con) daTitles.Fill(ds, "Titles") DataGridView1.DataSource = ds.Tables("Titles") DataGridView1.AutoResizeColumns() End Sub

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• How can I dynamically inject code to event handlers in Delphi?

  - by mjustin

  For debugging / performance tests I would like to dynamically add logging code to all event handlers of components of a given type. For example, for all Dataset components located ona TDatamodule, I would like to add some code for the BeforeOpen and the AfterOpen event to store the start and end time and send a line to a logger with the elapsed time in the AfterOpen event. I would prefer to do this dynamically (no component subclassing), so that I can add this to all existing datamodules and forms with minimal effort only when needed. Iterating all components and filtering by their type is easy, but for the components which already have event handlers assigned, I need a way to store the existing event handlers, and assign a new modified event handler which first does the logging and then will invoke the original code which was already present. Is there a design pattern which can be applied, or even some example code which shows how to implement this in Delphi?

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