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  • Function arguments VBA

    - by user1068249
    I have these three functions: When I run the first 2 functions, There's no problem, but when I run the last function (LMTD), It says 'Division by zero' yet when I debug some of the arguments have values, some don't. I know what I have to do, but I want to know why I have to do it, because it makes no sense to me. Tinn-function doesn't have Tut's arguments, so I have to add them to Tinn-function's arguments. Same goes for Tut, that doesn't know all of Tinn's arguments, and LMTD has to have both of Tinn and Tut's arguments. If I do that, it all runs smoothly. Why do I have to do this? Public Function Tinn(Tw, Qw, Qp, Q, deltaT) Tinn = (((Tw * Qw) + (Tut(Q, fd, mix) * Q)) / Qp) + deltaT End Function Public Function Tut(Q, fd, mix) Tut = Tinn(Tw, Qw, Qp, Q, deltaT) - (avgittEffektAiUiLMTD() / ((Q * fd * mix) / 3600)) End Function Public Function LMTD(Tsjo) LMTD = ((Tinn(Tw, Qw, Qp, Q, deltaT) - Tsjo) - (Tut(Q, fd, mix) - Tsjo)) / (WorksheetFunction.Ln ((Tinn(Tw, Qw, Qp, Q, deltaT) - Tsjo) / (Tut(Q, fd, mix) - Tsjo))) End Function

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  • How does dereferencing of a function pointer happen?

    - by eSKay
    Why and how does dereferencing a function pointer just "do nothing"? This is what I am talking about: #include<stdio.h> void hello() { printf("hello"); } int main(void) { (*****hello)(); } From a comment over here: function pointers dereference just fine, but the resulting function designator will be immediately converted back to a function pointer And from an answer here: Dereferencing (in way you think) a function's pointer means: accessing a CODE memory as it would be a DATA memory. Function pointer isn't suppose to be dereferenced in that way. Instead, it is called. I would use a name "dereference" side by side with "call". It's OK. Anyway: C is designed in such a way that both function name identifier as well as variable holding function's pointer mean the same: address to CODE memory. And it allows to jump to that memory by using call () syntax either on an identifier or variable. How exactly does dereferencing of a function pointer work?

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  • Node.js Adventure - When Node Flying in Wind

    - by Shaun
    In the first post of this series I mentioned some popular modules in the community, such as underscore, async, etc.. I also listed a module named “Wind (zh-CN)”, which is created by one of my friend, Jeff Zhao (zh-CN). Now I would like to use a separated post to introduce this module since I feel it brings a new async programming style in not only Node.js but JavaScript world. If you know or heard about the new feature in C# 5.0 called “async and await”, or you learnt F#, you will find the “Wind” brings the similar async programming experience in JavaScript. By using “Wind”, we can write async code that looks like the sync code. The callbacks, async stats and exceptions will be handled by “Wind” automatically and transparently.   What’s the Problem: Dense “Callback” Phobia Let’s firstly back to my second post in this series. As I mentioned in that post, when we wanted to read some records from SQL Server we need to open the database connection, and then execute the query. In Node.js all IO operation are designed as async callback pattern which means when the operation was done, it will invoke a function which was taken from the last parameter. For example the database connection opening code would be like this. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: } 8: }); And then if we need to query the database the code would be like this. It nested in the previous function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: } 14: }; 15: } 16: }); Assuming if we need to copy some data from this database to another then we need to open another connection and execute the command within the function under the query function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: target.open(targetConnectionString, function(error, t_conn) { 14: if(error) { 15: // connect failed 16: } 17: else { 18: t_conn.queryRaw(copy_command, function(error, results) { 19: if(error) { 20: // copy failed 21: } 22: else { 23: // and then, what do you want to do now... 24: } 25: }; 26: } 27: }; 28: } 29: }; 30: } 31: }); This is just an example. In the real project the logic would be more complicated. This means our application might be messed up and the business process will be fragged by many callback functions. I would like call this “Dense Callback Phobia”. This might be a challenge how to make code straightforward and easy to read, something like below. 1: try 2: { 3: // open source connection 4: var s_conn = sqlConnect(s_connectionString); 5: // retrieve data 6: var results = sqlExecuteCommand(s_conn, s_command); 7: 8: // open target connection 9: var t_conn = sqlConnect(t_connectionString); 10: // prepare the copy command 11: var t_command = getCopyCommand(results); 12: // execute the copy command 13: sqlExecuteCommand(s_conn, t_command); 14: } 15: catch (ex) 16: { 17: // error handling 18: }   What’s the Problem: Sync-styled Async Programming Similar as the previous problem, the callback-styled async programming model makes the upcoming operation as a part of the current operation, and mixed with the error handling code. So it’s very hard to understand what on earth this code will do. And since Node.js utilizes non-blocking IO mode, we cannot invoke those operations one by one, as they will be executed concurrently. For example, in this post when I tried to copy the records from Windows Azure SQL Database (a.k.a. WASD) to Windows Azure Table Storage, if I just insert the data into table storage one by one and then print the “Finished” message, I will see the message shown before the data had been copied. This is because all operations were executed at the same time. In order to make the copy operation and print operation executed synchronously I introduced a module named “async” and the code was changed as below. 1: async.forEach(results.rows, 2: function (row, callback) { 3: var resource = { 4: "PartitionKey": row[1], 5: "RowKey": row[0], 6: "Value": row[2] 7: }; 8: client.insertEntity(tableName, resource, function (error) { 9: if (error) { 10: callback(error); 11: } 12: else { 13: console.log("entity inserted."); 14: callback(null); 15: } 16: }); 17: }, 18: function (error) { 19: if (error) { 20: error["target"] = "insertEntity"; 21: res.send(500, error); 22: } 23: else { 24: console.log("all done."); 25: res.send(200, "Done!"); 26: } 27: }); It ensured that the “Finished” message will be printed when all table entities had been inserted. But it cannot promise that the records will be inserted in sequence. It might be another challenge to make the code looks like in sync-style? 1: try 2: { 3: forEach(row in rows) { 4: var entity = { /* ... */ }; 5: tableClient.insert(tableName, entity); 6: } 7:  8: console.log("Finished"); 9: } 10: catch (ex) { 11: console.log(ex); 12: }   How “Wind” Helps “Wind” is a JavaScript library which provides the control flow with plain JavaScript for asynchronous programming (and more) without additional pre-compiling steps. It’s available in NPM so that we can install it through “npm install wind”. Now let’s create a very simple Node.js application as the example. This application will take some website URLs from the command arguments and tried to retrieve the body length and print them in console. Then at the end print “Finish”. I’m going to use “request” module to make the HTTP call simple so I also need to install by the command “npm install request”. The code would be like this. 1: var request = require("request"); 2:  3: // get the urls from arguments, the first two arguments are `node.exe` and `fetch.js` 4: var args = process.argv.splice(2); 5:  6: // main function 7: var main = function() { 8: for(var i = 0; i < args.length; i++) { 9: // get the url 10: var url = args[i]; 11: // send the http request and try to get the response and body 12: request(url, function(error, response, body) { 13: if(!error && response.statusCode == 200) { 14: // log the url and the body length 15: console.log( 16: "%s: %d.", 17: response.request.uri.href, 18: body.length); 19: } 20: else { 21: // log error 22: console.log(error); 23: } 24: }); 25: } 26: 27: // finished 28: console.log("Finished"); 29: }; 30:  31: // execute the main function 32: main(); Let’s execute this application. (I made them in multi-lines for better reading.) 1: node fetch.js 2: "http://www.igt.com/us-en.aspx" 3: "http://www.igt.com/us-en/games.aspx" 4: "http://www.igt.com/us-en/cabinets.aspx" 5: "http://www.igt.com/us-en/systems.aspx" 6: "http://www.igt.com/us-en/interactive.aspx" 7: "http://www.igt.com/us-en/social-gaming.aspx" 8: "http://www.igt.com/support.aspx" Below is the output. As you can see the finish message was printed at the beginning, and the pages’ length retrieved in a different order than we specified. This is because in this code the request command, console logging command are executed asynchronously and concurrently. Now let’s introduce “Wind” to make them executed in order, which means it will request the websites one by one, and print the message at the end.   First of all we need to import the “Wind” package and make sure the there’s only one global variant named “Wind”, and ensure it’s “Wind” instead of “wind”. 1: var Wind = require("wind");   Next, we need to tell “Wind” which code will be executed asynchronously so that “Wind” can control the execution process. In this case the “request” operation executed asynchronously so we will create a “Task” by using a build-in helps function in “Wind” named Wind.Async.Task.create. 1: var requestBodyLengthAsync = function(url) { 2: return Wind.Async.Task.create(function(t) { 3: request(url, function(error, response, body) { 4: if(error || response.statusCode != 200) { 5: t.complete("failure", error); 6: } 7: else { 8: var data = 9: { 10: uri: response.request.uri.href, 11: length: body.length 12: }; 13: t.complete("success", data); 14: } 15: }); 16: }); 17: }; The code above created a “Task” from the original request calling code. In “Wind” a “Task” means an operation will be finished in some time in the future. A “Task” can be started by invoke its start() method, but no one knows when it actually will be finished. The Wind.Async.Task.create helped us to create a task. The only parameter is a function where we can put the actual operation in, and then notify the task object it’s finished successfully or failed by using the complete() method. In the code above I invoked the request method. If it retrieved the response successfully I set the status of this task as “success” with the URL and body length. If it failed I set this task as “failure” and pass the error out.   Next, we will change the main() function. In “Wind” if we want a function can be controlled by Wind we need to mark it as “async”. This should be done by using the code below. 1: var main = eval(Wind.compile("async", function() { 2: })); When the application is running, Wind will detect “eval(Wind.compile(“async”, function” and generate an anonymous code from the body of this original function. Then the application will run the anonymous code instead of the original one. In our example the main function will be like this. 1: var main = eval(Wind.compile("async", function() { 2: for(var i = 0; i < args.length; i++) { 3: try 4: { 5: var result = $await(requestBodyLengthAsync(args[i])); 6: console.log( 7: "%s: %d.", 8: result.uri, 9: result.length); 10: } 11: catch (ex) { 12: console.log(ex); 13: } 14: } 15: 16: console.log("Finished"); 17: })); As you can see, when I tried to request the URL I use a new command named “$await”. It tells Wind, the operation next to $await will be executed asynchronously, and the main thread should be paused until it finished (or failed). So in this case, my application will be pause when the first response was received, and then print its body length, then try the next one. At the end, print the finish message.   Finally, execute the main function. The full code would be like this. 1: var request = require("request"); 2: var Wind = require("wind"); 3:  4: var args = process.argv.splice(2); 5:  6: var requestBodyLengthAsync = function(url) { 7: return Wind.Async.Task.create(function(t) { 8: request(url, function(error, response, body) { 9: if(error || response.statusCode != 200) { 10: t.complete("failure", error); 11: } 12: else { 13: var data = 14: { 15: uri: response.request.uri.href, 16: length: body.length 17: }; 18: t.complete("success", data); 19: } 20: }); 21: }); 22: }; 23:  24: var main = eval(Wind.compile("async", function() { 25: for(var i = 0; i < args.length; i++) { 26: try 27: { 28: var result = $await(requestBodyLengthAsync(args[i])); 29: console.log( 30: "%s: %d.", 31: result.uri, 32: result.length); 33: } 34: catch (ex) { 35: console.log(ex); 36: } 37: } 38: 39: console.log("Finished"); 40: })); 41:  42: main().start();   Run our new application. At the beginning we will see the compiled and generated code by Wind. Then we can see the pages were requested one by one, and at the end the finish message was printed. Below is the code Wind generated for us. As you can see the original code, the output code were shown. 1: // Original: 2: function () { 3: for(var i = 0; i < args.length; i++) { 4: try 5: { 6: var result = $await(requestBodyLengthAsync(args[i])); 7: console.log( 8: "%s: %d.", 9: result.uri, 10: result.length); 11: } 12: catch (ex) { 13: console.log(ex); 14: } 15: } 16: 17: console.log("Finished"); 18: } 19:  20: // Compiled: 21: /* async << function () { */ (function () { 22: var _builder_$0 = Wind.builders["async"]; 23: return _builder_$0.Start(this, 24: _builder_$0.Combine( 25: _builder_$0.Delay(function () { 26: /* var i = 0; */ var i = 0; 27: /* for ( */ return _builder_$0.For(function () { 28: /* ; i < args.length */ return i < args.length; 29: }, function () { 30: /* ; i ++) { */ i ++; 31: }, 32: /* try { */ _builder_$0.Try( 33: _builder_$0.Delay(function () { 34: /* var result = $await(requestBodyLengthAsync(args[i])); */ return _builder_$0.Bind(requestBodyLengthAsync(args[i]), function (result) { 35: /* console.log("%s: %d.", result.uri, result.length); */ console.log("%s: %d.", result.uri, result.length); 36: return _builder_$0.Normal(); 37: }); 38: }), 39: /* } catch (ex) { */ function (ex) { 40: /* console.log(ex); */ console.log(ex); 41: return _builder_$0.Normal(); 42: /* } */ }, 43: null 44: ) 45: /* } */ ); 46: }), 47: _builder_$0.Delay(function () { 48: /* console.log("Finished"); */ console.log("Finished"); 49: return _builder_$0.Normal(); 50: }) 51: ) 52: ); 53: /* } */ })   How Wind Works Someone may raise a big concern when you find I utilized “eval” in my code. Someone may assume that Wind utilizes “eval” to execute some code dynamically while “eval” is very low performance. But I would say, Wind does NOT use “eval” to run the code. It only use “eval” as a flag to know which code should be compiled at runtime. When the code was firstly been executed, Wind will check and find “eval(Wind.compile(“async”, function”. So that it knows this function should be compiled. Then it utilized parse-js to analyze the inner JavaScript and generated the anonymous code in memory. Then it rewrite the original code so that when the application was running it will use the anonymous one instead of the original one. Since the code generation was done at the beginning of the application was started, in the future no matter how long our application runs and how many times the async function was invoked, it will use the generated code, no need to generate again. So there’s no significant performance hurt when using Wind.   Wind in My Previous Demo Let’s adopt Wind into one of my previous demonstration and to see how it helps us to make our code simple, straightforward and easy to read and understand. In this post when I implemented the functionality that copied the records from my WASD to table storage, the logic would be like this. 1, Open database connection. 2, Execute a query to select all records from the table. 3, Recreate the table in Windows Azure table storage. 4, Create entities from each of the records retrieved previously, and then insert them into table storage. 5, Finally, show message as the HTTP response. But as the image below, since there are so many callbacks and async operations, it’s very hard to understand my logic from the code. Now let’s use Wind to rewrite our code. First of all, of course, we need the Wind package. Then we need to include the package files into project and mark them as “Copy always”. Add the Wind package into the source code. Pay attention to the variant name, you must use “Wind” instead of “wind”. 1: var express = require("express"); 2: var async = require("async"); 3: var sql = require("node-sqlserver"); 4: var azure = require("azure"); 5: var Wind = require("wind"); Now we need to create some async functions by using Wind. All async functions should be wrapped so that it can be controlled by Wind which are open database, retrieve records, recreate table (delete and create) and insert entity in table. Below are these new functions. All of them are created by using Wind.Async.Task.create. 1: sql.openAsync = function (connectionString) { 2: return Wind.Async.Task.create(function (t) { 3: sql.open(connectionString, function (error, conn) { 4: if (error) { 5: t.complete("failure", error); 6: } 7: else { 8: t.complete("success", conn); 9: } 10: }); 11: }); 12: }; 13:  14: sql.queryAsync = function (conn, query) { 15: return Wind.Async.Task.create(function (t) { 16: conn.queryRaw(query, function (error, results) { 17: if (error) { 18: t.complete("failure", error); 19: } 20: else { 21: t.complete("success", results); 22: } 23: }); 24: }); 25: }; 26:  27: azure.recreateTableAsync = function (tableName) { 28: return Wind.Async.Task.create(function (t) { 29: client.deleteTable(tableName, function (error, successful, response) { 30: console.log("delete table finished"); 31: client.createTableIfNotExists(tableName, function (error, successful, response) { 32: console.log("create table finished"); 33: if (error) { 34: t.complete("failure", error); 35: } 36: else { 37: t.complete("success", null); 38: } 39: }); 40: }); 41: }); 42: }; 43:  44: azure.insertEntityAsync = function (tableName, entity) { 45: return Wind.Async.Task.create(function (t) { 46: client.insertEntity(tableName, entity, function (error, entity, response) { 47: if (error) { 48: t.complete("failure", error); 49: } 50: else { 51: t.complete("success", null); 52: } 53: }); 54: }); 55: }; Then in order to use these functions we will create a new function which contains all steps for data copying. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: } 4: catch (ex) { 5: console.log(ex); 6: res.send(500, "Internal error."); 7: } 8: })); Let’s execute steps one by one with the “$await” keyword introduced by Wind so that it will be invoked in sequence. First is to open the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: } 7: catch (ex) { 8: console.log(ex); 9: res.send(500, "Internal error."); 10: } 11: })); Then retrieve all records from the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: } 10: catch (ex) { 11: console.log(ex); 12: res.send(500, "Internal error."); 13: } 14: })); After recreated the table, we need to create the entities and insert them into table storage. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: } 24: } 25: catch (ex) { 26: console.log(ex); 27: res.send(500, "Internal error."); 28: } 29: })); Finally, send response back to the browser. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: // send response 24: console.log("all done"); 25: res.send(200, "All done!"); 26: } 27: } 28: catch (ex) { 29: console.log(ex); 30: res.send(500, "Internal error."); 31: } 32: })); If we compared with the previous code we will find now it became more readable and much easy to understand. It’s very easy to know what this function does even though without any comments. When user go to URL “/was/copyRecords” we will execute the function above. The code would be like this. 1: app.get("/was/copyRecords", function (req, res) { 2: copyRecords(req, res).start(); 3: }); And below is the logs printed in local compute emulator console. As we can see the functions executed one by one and then finally the response back to me browser.   Scaffold Functions in Wind Wind provides not only the async flow control and compile functions, but many scaffold methods as well. We can build our async code more easily by using them. I’m going to introduce some basic scaffold functions here. In the code above I created some functions which wrapped from the original async function such as open database, create table, etc.. All of them are very similar, created a task by using Wind.Async.Task.create, return error or result object through Task.complete function. In fact, Wind provides some functions for us to create task object from the original async functions. If the original async function only has a callback parameter, we can use Wind.Async.Binding.fromCallback method to get the task object directly. For example the code below returned the task object which wrapped the file exist check function. 1: var Wind = require("wind"); 2: var fs = require("fs"); 3:  4: fs.existsAsync = Wind.Async.Binding.fromCallback(fs.exists); In Node.js a very popular async function pattern is that, the first parameter in the callback function represent the error object, and the other parameters is the return values. In this case we can use another build-in function in Wind named Wind.Async.Binding.fromStandard. For example, the open database function can be created from the code below. 1: sql.openAsync = Wind.Async.Binding.fromStandard(sql.open); 2:  3: /* 4: sql.openAsync = function (connectionString) { 5: return Wind.Async.Task.create(function (t) { 6: sql.open(connectionString, function (error, conn) { 7: if (error) { 8: t.complete("failure", error); 9: } 10: else { 11: t.complete("success", conn); 12: } 13: }); 14: }); 15: }; 16: */ When I was testing the scaffold functions under Wind.Async.Binding I found for some functions, such as the Azure SDK insert entity function, cannot be processed correctly. So I personally suggest writing the wrapped method manually.   Another scaffold method in Wind is the parallel tasks coordination. In this example, the steps of open database, retrieve records and recreated table should be invoked one by one, but it can be executed in parallel when copying data from database to table storage. In Wind there’s a scaffold function named Task.whenAll which can be used here. Task.whenAll accepts a list of tasks and creates a new task. It will be returned only when all tasks had been completed, or any errors occurred. For example in the code below I used the Task.whenAll to make all copy operation executed at the same time. 1: var copyRecordsInParallel = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage in parallal 14: var tasks = new Array(results.rows.length); 15: for (var i = 0; i < results.rows.length; i++) { 16: var entity = { 17: "PartitionKey": results.rows[i][1], 18: "RowKey": results.rows[i][0], 19: "Value": results.rows[i][2] 20: }; 21: tasks[i] = azure.insertEntityAsync(tableName, entity); 22: } 23: $await(Wind.Async.Task.whenAll(tasks)); 24: // send response 25: console.log("all done"); 26: res.send(200, "All done!"); 27: } 28: } 29: catch (ex) { 30: console.log(ex); 31: res.send(500, "Internal error."); 32: } 33: })); 34:  35: app.get("/was/copyRecordsInParallel", function (req, res) { 36: copyRecordsInParallel(req, res).start(); 37: });   Besides the task creation and coordination, Wind supports the cancellation solution so that we can send the cancellation signal to the tasks. It also includes exception solution which means any exceptions will be reported to the caller function.   Summary In this post I introduced a Node.js module named Wind, which created by my friend Jeff Zhao. As you can see, different from other async library and framework, adopted the idea from F# and C#, Wind utilizes runtime code generation technology to make it more easily to write async, callback-based functions in a sync-style way. By using Wind there will be almost no callback, and the code will be very easy to understand. Currently Wind is still under developed and improved. There might be some problems but the author, Jeff, should be very happy and enthusiastic to learn your problems, feedback, suggestion and comments. You can contact Jeff by - Email: [email protected] - Group: https://groups.google.com/d/forum/windjs - GitHub: https://github.com/JeffreyZhao/wind/issues   Source code can be download here.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • MYSQL in PHPMYADMIN - create table relationship from one table

    - by Stanley DecoWood
    I want to create a table relationship with MYSQL PHPMYADMIN. I have this Create table: CREATE TABLE students(code_students int(8)not null AUTO_INCREMENT, name_students varchar(25), age_students int(3), degree_program varchar(25), code_advisor int(8)not null, primary key(code_students, code_advisor) ); and i want to make a create table named advise relationship between code_students, code_advisor.

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  • How to Edit Permission on "Create" in MOSS07?

    - by DanSogaard
    When you go to Lists, and Create. I'd like to show the "Custom Lists" column only to specific group. I don't want the users to be able to create Web Pages, Document Libs .. etc But I'm not able to see how, I tried to create a custom group and edit permission level, but I cant find where exactly. does enabling "Create" to specific group opens all settings inside that you can't eliminate certain settings from showing to this group?.

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  • How to Edit Permission on "Create"? SharePoint

    - by DanSogaard
    When you go to Lists, and Create. I'd like to show the "Custom Lists" column only to specific group. I don't want the users to be able to create Web Pages, Document Libs .. etc But I'm not able to see how, I tried to create a custom group and edit permission level, but I cant find where exactly. does enabling "Create" to specific group opens all settings inside that you can't eliminate certain settings from showing to this group?.

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  • JavaScript setTimeout setInterval within one function

    - by dagoof
    I think I might be overtired but I cannot for the life of me make sense of this, and I think it's due to a lack of knowledge of javascript var itv=function(){ return setInterval(function(){ sys.puts('interval'); }, 1000); } var tout=function(itv){ return setTimeout(function(){ sys.puts('timeout'); clearInterval(itv); }, 5500); } With these two functions I can call a=tout(itv()); and get a looping timer to run for 5.5 seconds and then exit, essentially. By my logic, this should work but it simply is not var dotime=function(){ return setTimeout(function(){ clearInterval(function(){ return setInterval(function(){ sys.puts("interval"); }, 1000); }); }, 5500); } any insight in this matter would be appreciated.

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  • jQuery calling a predefined function

    - by Mircea
    I have a big function defined and executed on an element click. Is there a way to execute again that "big" function later, call it somehow, without writing it again? $('#element').click(function(big){ some big function ... ... }); $('#another_element').click(function(){ this should execute the previous "big" function }); Thanx.

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  • In javascript, how do I find out the name of a function from within that function?

    - by roryhewitt
    The title should make it clear. Is it possible from within a function to determine the name of that function? Basically, I'm adding some debugging code to a number of functions, and I'd like to be able to simply add the following line inside every function: if (global_debugOn) alert("Processing function " + function-name); How can I get 'function-name'? Yes, obviously I could simply type in the function name (after all I'm typing in the whole alert bit), but that's a hassle to do, especially if there is a nice simple way of retrieving it dynamically. Plus, as function names change during development, I'd like to keep it up-to-date... I hoped that maybe the arguments attribute might hold this (e.g. arguments[0], like in C), but I couldn't get it to work. I'm not even sure if arguments works anyway. Thanks! Rory

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  • How to structure javascript callback so that function scope is maintained properly

    - by Chetan
    I'm using XMLHttpRequest, and I want to access a local variable in the success callback function. Here is the code: function getFileContents(filePath, callbackFn) { var xhr = new XMLHttpRequest(); xhr.onreadystatechange = function() { if (xhr.readyState == 4) { callbackFn(xhr.responseText); } } xhr.open("GET", chrome.extension.getURL(filePath), true); xhr.send(); } And I want to call it like this: var test = "lol"; getFileContents("hello.js", function(data) { alert(test); }); Here, test would be out of the scope of the callback function, since only the enclosing function's variables are accessible inside the callback function. What is the best way to pass test to the callback function so the alert(test); will display test correctly?

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  • ASP.NET (VB) - Close an opened SQL connection inside Function

    - by B1GB0Y
    Can anyone tell me how I close an opened SQL connection inside a Function? I call a Select Function like this: Function Selec(ByVal SQLStr As String) As SqlDataReader Dim SQLConn As New SqlConnection() Dim SQLCmd As New SqlCommand() SQLConn.ConnectionString = Session("bd") SQLConn.Open() SQLCmd.Connection = SQLConn SQLCmd.CommandText = SQLStr Selec = SQLCmd.ExecuteReader End Function And in another page I do a While method to retrieve me the data like this: (Note: BDcon.BD is the name of the Class that have Functions) Dim write as New BDcon.BD Dim menu As SqlDataReader = writeBD.Selec("SELECT something from Table") While menu.Read 'Do something End While menu.Close 'This close just the DataReader and not the SqlConnection Finally I want to Close my SQL Connection by Function like this: Function Close() As SqlConnection Dim SQLConn As New SqlConnection() SQLConn.ConnectionString = Session("bd") SQLConn.Close() End Function I think that the problem is on the Close() Function, I want to close the connection but I don't know how to call my Opened Conneciton. Please anyone can help me? Thanks in advance :)

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  • JavaScript Loop and wait for function

    - by Fluidbyte
    I have a simple single-dimension array, let's say: fruits = ["apples","bananas","oranges","peaches","plums"]; I can loop thru with with $.each() function: $.each(fruits, function(index, fruit) { showFruit(fruit); }); but I'm calling to another function which I need to finish before moving on to the next item. So, if I have a function like this: function showFruit(fruit){ $.getScript('some/script.js',function(){ // Do stuff }) } What's the best way to make sure the previous fruit has been appended before moving on?

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  • PHP Commercial Project Function define

    - by Shiro
    Currently I am working with a commercial project with PHP. I think this question not really apply to PHP for all programming language, just want to discuss how your guys solve it. I work in MVC framework (CodeIgniter). all the database transaction code in model class. Previously, I seperate different search criteria with different function name. Just an example function get_student_detail_by_ID($id){} function get_student_detail_by_name($name){} as you can see the function actually can merge to one, just add a parameter for it. But something you are rushing with project, you won't look back previously got what similar function just make some changes can meet the goal. In this case, we found that there is a lot function there and hard to maintenance. Recently, we try to group the entity to one ultimate search something like this function get_ResList($is_row_count=FALSE, $record_start=0, $arr_search_criteria='', $paging_limit=20, $orderby='name', $sortdir='ASC') we try to make this function to fit all the searching criteria. However, our system getting bigger and bigger, the search criteria not more 1-2 tables. It require join with other table with different purpose. What we had done is using IF ELSE, if(bla bla bla) { $sql_join = JOIN_SOME_TABLE; $sql_where = CONDITION; } at the end, we found that very hard to maintance the function. it is very hard to debug as well. I would like to ask your opinion, what is the commercial solution they solve this kind of issue, how to define a function and how to revise it. I think this is link project management skill. Hope you willing to share with us. Thanks.

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  • Why can't I call this function (javascript/jquery)

    - by Ankur
    This is driving me nuts .... I have written a function function seraliseQuery(){ for(var i=1; i<=variables;i++){ alert(queryPreds[i]+" - "+queryObjs[i]); } } I just want to be able to call it from my other function $(".object").click( function() { // code removed seraliseQuery(); }); The error I get is "the function serialiseQuery() is undefined". Everything is within $(document).ready( function() { // code goes here }

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  • Create a callback function within a custom jQuery function

    - by Thomas
    I'm not sure how to approach this as I am fairly new to jQuery. I'm wanting to create a callback function within a custom function. Here's my example: function doSomething() { var output = 'output here'; // Do something here // This is where I want to create the callback function and pass output as a parameter } I want the callback function to be accessible by any number of scripts (e.g. more than one script can access this callback). This function (doSomething) is not part of a plugin but rather part of another callback function itself. I've also created a var within the function and want to pass that through the callback function as well. How can I do this?

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  • Pointer to a C++ class member function as a global function's parameter?

    - by marcin1400
    I have got a problem with calling a global function, which takes a pointer to a function as a parameter. Here is the declaration of the global function: int lmdif ( minpack_func_mn fcn, void *p, int m, int n, double *x, double *fvec, double ftol) The "minpack_func_mn" symbol is a typedef for a pointer to a function, defined as: typedef int (*minpack_func_mn)(void *p, int m, int n, const double *x, double *fvec, int iflag ); I want to call the "lmdif" function with a pointer to a function which is a member of a class I created, and here is the declaration of this class function: int LT_Calibrator::fcn(void *p, int m, int n, const double *x, double *fvec,int iflag) I am calling a global function like this: info=lmdif(&LT_Calibrator::fcn, 0, m, n, x, fvec, ftol) Unfortunately, I get a compiler error, which says: "error C2664: 'lmdif' : cannot convert parameter 1 from 'int (__thiscall LT_Calibrator::* )(void *,int,int,const double *,double *,int)' to 'minpack_func_mn' 1 There is no context in which this conversion is possible" Is there any way to solve that problem?

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  • Undefined function in php

    - by Bidyut
    I wrote three methods in a class and one is calling another, but when I call the function outside through the object, it is showing an undefined function error for the second function. Here's my code: function resize_image(){ } function image_resize(){ $a = resize_image(); } When I run this, it shows resize_image() as undefined. Here's the error: Fatal error: Call to undefined function resize_image() in /home/vacayge/public_html/Major/Alpha1/classes/cUserImages.php on line 2090

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  • Caller property of JS for "foo = function()" style of coding

    - by arvind
    I want to use the property of "caller" for a function which is defined here It works fine for this style of function declaration function g() { alert(g.caller.name) // f } function f() { alert(f.caller.name) // undefined g() } f() JSfiddle for this But then my function declaration is something like g = function() { alert(g.caller.name) // expected f, getting undefined } f = function() { alert("calling f") alert(f.caller.name) // undefined g() } f() and I am getting undefined (basically not getting anything) JSfiddle for this Is there any way that I can use the caller property without having to rewrite my code? Also, I hope I have not made any mistakes in usage and function declaration since I am quite new to using JS.

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  • Actionscript: Switching back into previous function from event handler function

    - by J.Ded.
    I need to return to my original function after capturing an event (downloading something) with another function. The original function needs to return a value, which depends on the downloaded data. So, I'd like to pause original function for the time needed for the download and the eventhandler function to complete it's work, and resume it afterwards. The obvious way is to set a flag value (both the original function and the eventhandler are within the same class) and make the original function check it until the eventhandler function changes the flag. But that would be wasteful, and my AS is slow enough already:) [other parts of the application utilise some heavy graphics]. Is there another way? Like an event that gets captured "in the middle" of the function? Or some other form of flow control?

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  • R programming function without ()

    - by Mark Kennedy
    So, I Have the following very simple map.r file. I'm trying to have the user type "click" in interactive mode and then have the function . Since it's a function, the user has to type "click()" how can I make it so that they only have to the word (w/o parentheses), and then have that function do something with the img. So the user types: mydist("image.pnm") click //And then the function click does what it's supposed to mydist <- function(mapfile) { img <- read.pnm(mapfile) plot(img) } click <- function() { //Prompt user to click on img }

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  • Laptop Function Key Dysfunctional

    - by Kanini
    My laptop has Windows Vista installed in it. Everytime, I switch on the computer, the function key seems to be enabled automatically. So, when I press i, 5 is displayed and so on and so forth. Now, I have checked and ensured that Function is key is not locked due to a faulty keyboard or coke spilling on it and suchlike. I am able to get out of it with the following key combination Fn + Ctrl + Ins (Num Lk) However, the next time I switch on my PC, the Function key is automatically enabled. Also, if my computer goes to sleep mode and comes back, it is enabled again. Anything that I can do to change this behaviour?

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  • Excel VBA Function runtime error 1004: Application-defined or object-defined error

    - by music2myear
    I'm trying to learn functions for the purpose of simplifying and reusing code whenever necessary. I began by turning something I use pretty often into a function: Returning the integer value of the last non-blank row in a spreadsheet. Function FindLastDataLine(strColName As String) As Long FindLastDataLine = Range(strColName).Offset(Rows.Count - 1, 0).End(xlUp).Row End Function Sub PracticeMacro() intItemCount = FindLastDataLine("A:A") MsgBox ("There are " & intItemCount & " rows of data in column A.") End Sub When I run this I recieve the runtime error '1004' "Application-defined or object-defined error" which Help helpfully defines as "someone else's fault" to quote not quite verbatim. Where might I be going wrong?

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  • I want to use blur function instead mouseup function

    - by yossi
    I have the Demo Table which I can click on the cell(td tag) and I can change the value on it.direct php DataBase. to do that I need to contain two tags.1 - span. 2 - input. like the below. <td class='Name'> <span id="spanName1" class="text" style="display: inline;"> Somevalue </span> <input type="text" value="Somevalue" class="edittd" id="inputName1" style="display: none; "> </td> to control on the data inside the cell I use in jquery .mouseup function. mouseup work but also make truble. I need to replace it with blur function but when I try to replace mouseup with blur the program thas not work becose, when I click on the cell I able to enter the input tag and I can change the value but I can't Successful to Leave the tag/field by clicking out side the table, which alow me to update the DataBase you can see that Demo with blur Here. what you advice me to do? $(".edittd").mouseup(function() { return false; }); //************* $(document).mouseup(function() { $('#span' + COLUME + ROW).show(); $('#input'+ COLUME + ROW ).hide(); VAL = $("#input" + COLUME + ROW).val(); $("#span" + COLUME + ROW).html(VAL); if(STATUS != VAL){ //******ajax code //dataString = $.trim(this.value); $.ajax({ type: "POST", dataType: 'html', url: "./public/php/ajax.php", data: 'COLUME='+COLUME+'&ROW='+ROW+'&VAL='+VAL, //{"dataString": dataString} cache: false, success: function(data) { $("#statuS").html(data); } }); //******end ajax $('#statuS').removeClass('statuSnoChange') .addClass('statuSChange'); $('#statuS').html('THERE IS CHANGE'); $('#tables').load('TableEdit2.php'); } else { //alert(DATASTRING+'status not true'); } });//End mouseup function I change it to: $(document).ready(function() { var COLUMES,COLUME,VALUE,VAL,ROWS,ROW,STATUS,DATASTRING; $('td').click(function() { COLUME = $(this).attr('class'); }); //**************** $('tr').click(function() { ROW = $(this).attr('id'); $('#display_Colume_Raw').html(COLUME+ROW); $('#span' + COLUME + ROW).hide(); $('#input'+ COLUME + ROW ).show(); STATUS = $("#input" + COLUME + ROW).val(); }); //******************** $(document).blur(function() { $('#span' + COLUME + ROW).show(); $('#input'+ COLUME + ROW ).hide(); VAL = $("#input" + COLUME + ROW).val(); $("#span" + COLUME + ROW).html(VAL); if(STATUS != VAL){ //******ajax code //dataString = $.trim(this.value); $.ajax({ type: "POST", dataType: 'html', url: "./public/php/ajax.php", data: 'COLUME='+COLUME+'&ROW='+ROW+'&VAL='+VAL, //{"dataString": dataString} cache: false, success: function(data) { $("#statuS").html(data); } }); //******end ajax $('#statuS').removeClass('statuSnoChange') .addClass('statuSChange'); $('#statuS').html('THERE IS CHANGE'); $('#tables').load('TableEdit2.php'); } else { //alert(DATASTRING+'status not true'); } });//End mouseup function $('#save').click (function(){ var input1,input2,input3,input4=""; input1 = $('#input1').attr('value'); input2 = $('#input2').attr('value'); input3 = $('#input3').attr('value'); input4 = $('#input4').attr('value'); $.ajax({ type: "POST", url: "./public/php/ajax.php", data: "input1="+ input1 +"&input2="+ input2 +"&input3="+ input3 +"&input4="+ input4, success: function(data){ $("#statuS").html(data); $('#tbl').hide(function(){$('div.success').fadeIn();}); $('#tables').load('TableEdit2.php'); } }); }); }); Thx

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  • VBA Public Function to Excel

    - by Sugih
    Dear sir , I have create below function Option Explicit Public Function fyi(x As Double, f As String) As String Application.Volatile Dim data As Double Dim post(5) post(1) = "Ribu " post(2) = "Juta " post(3) = "Milyar " post(4) = "Trilyun " post(5) = "Ribu Trilyun " Dim part As String Dim text As String Dim cond As Boolean Dim i As Integer If (x < 0) Then fyi = " " Exit Function End If If (x = 0) Then fyi = "Nol" Exit Function End If If (x < 2000) Then cond = True End If text = " " If (x >= 1E+15) Then fyi = "Nilai Terlalu Besar" Exit Function End If For i = 4 To 1 Step -1 data = Int(x / (10 ^ (3 * i))) If (data 0) Then part = fyis(data, cond) text = text & part & post(i) End If x = x - data * (10 ^ (3 * i)) Next text = text & fyis(x, False) fyi = text & f End Function Function fyis(ByVal y As Double, ByVal conds As Boolean) As String Dim datas As Double Dim posts(2) posts(1) = "Puluh" posts(2) = "Ratus" Dim parts As String Dim texts As String 'Dim conds As Boolean Dim j As Integer Dim value(9) value(1) = "Se" value(2) = "Dua " value(3) = "Tiga " value(4) = "Empat " value(5) = "Lima " value(6) = "Enam " value(7) = "Tujuh " value(8) = "Delapan " value(9) = "Sembilan " texts = " " For j = 2 To 1 Step -1 datas = Int(y / 10 ^ j) If (datas 0) Then parts = value(datas) If (j = 1 And datas = 1) Then y = y - datas * 10 ^ j If (y = 1) Then posts(j) = "belas" Else value(y) = "Se" End If texts = texts & value(y) & posts(j) fyis = texts Exit Function Else texts = texts & parts & posts(j) End If End If y = y - datas * 10 ^ j Next If (conds = False) Then value(1) = "Satu " End If texts = texts & value(y) fyis = texts End Function but when I return to Excel and type '=fyi(500,"USD") it return to #name? please do me favor to inform me how to solve Rgds, Sugih

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