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  • Issue reading in a cell from Excel with Apache POI

    - by Nick
    I am trying to use Apache POI to read in old (pre-2007 and XLS) Excel files. My program goes to the end of the rows and iterates back up until it finds something that's not either null or empty. Then it iterates back up a few times and grabs those cells. This program works just fine reading in XLSX and XLS files made in Office 2010. I get the following error message: Exception in thread "main" java.lang.NumberFormatException: empty String at sun.misc.FloatingDecimal.readJavaFormatString(Unknown Source) at java.lang.Double.parseDouble(Unknown Source) at the line: num = Double.parseDouble(str); from the code: str = cell.toString(); if (str != "" || str != null) { System.out.println("Cell is a string"); num = Double.parseDouble(str); } else { System.out.println("Cell is numeric."); num = cell.getNumericCellValue(); } where the cell is the last cell in the document that's not empty or null. When I try to print the first cell that's not empty or null, it prints nothing, so I think I'm not accessing it correctly.

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  • How do I implement configurations and settings?

    - by Malvolio
    I'm writing a system that is deployed in several places and each site needs its own configurations and settings. A "configuration" is a named value that is necessary to a particular site (e.g., the database URL, S3 bucket name); every configuration is necessary, there is not usually a default, and it's typically string-valued. A setting is a named value but it just tweaks the behavior of the system; it's often numeric or Boolean, and there's usually some default. So far, I've been using property files or thing like them, but it's a terrible solution. Several times, a developer has added a requirement for a configuration but not added the value to file for the live configuration, so the new release passed all the tests, then failed when released to live. Better, of course, for every file to be compiled — so if there's a missing configuration, or one of the wrong type, it won't get past the compiler — and inject the site-specific class into the build for each site. As a bones, a Scala file can easy model more complex values, especially lists, but also maps and tuples. The downside is, the files are sometimes maintained by people who aren't developers, so it has to be pretty self-explanatory, which was the advantage of property files. (Someone explain XML configurations to me: all the complexity of a compilable file but the run-time risk of a property file.) What I'm looking for is an easy pattern for defining a group required names and allowable values. Any suggestions?

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  • Technique for selectively formatting data in a PowerShell pipeline and output as HTML

    - by halr9000
    Say that you want to do some fancy formatting of some tabular output from powershell, and the destination is to be html (either for a webserver, or to be sent in an email). Let's say for example that you want certain numeric values to have a different background color. Whatever. I can think of two solid programmatic ways to accomplish this: output XML and transform with XSLT, or output HTML and decorate with CSS. XSLT is probably the harder of the two (I say that because I don't know it), but from what little I recall, it has the benefit of bring able to embed the selection criteria (xpath?) for aforementioned fancy formatting. CSS on the other hand needs a helping hand. If you wanted a certain cell to be treated specially, then you would need to distinguish it from its siblings with a class, id, or something along those lines. PowerShell doesn't really have a way to do that natively, so that would mean parsing the HTML as it leaves convertto-html and adding, for example, a "emphasis" class: <td class="emphasis">32MB</td> I don't like the idea of the required text parsing, especially given that I would rather be able to somehow emphasize what needs emphasizing in Powershell before it hits HTML. Is XSLT the best way? Have suggestions for how to markup the HTML after it leaves convertto-html or ideas of a different way?

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  • Why doesn't java.lang.Number implement Comparable?

    - by Julien Chastang
    Does anyone know why java.lang.Number does not implement Comparable? This means that you cannot sort Numbers with Collections.sort which seems to me a little strange. Post discussion update: Thanks for all the helpful responses. I ended up doing some more research about this topic. The simplest explanation for why java.lang.Number does not implement Comparable is rooted in mutability concerns. For a bit of review, java.lang.Number is the abstract super-type of AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, Double, Float, Integer, Long and Short. On that list, AtomicInteger and AtomicLong to do not implement Comparable. Digging around, I discovered that it is not a good practice to implement Comparable on mutable types because the objects can change during or after comparison rendering the result of the comparison useless. Both AtomicLong and AtomicInteger are mutable. The API designers had the forethought to not have Number implement Comparable because it would have constrained implementation of future subtypes. Indeed, AtomicLong and AtomicInteger were added in Java 1.5 long after java.lang.Number was initially implemented. Apart from mutability, there are probably other considerations here too. A compareTo implementation in Number would have to promote all numeric values to BigDecimal because it is capable of accommodating all the Number sub-types. The implication of that promotion in terms of mathematics and performance is a bit unclear to me, but my intuition finds that solution kludgy.

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  • How do I send floats in window messages.

    - by yngvedh
    Hi, What is the best way to send a float in a windows message using c++ casting operators? The reason I ask is that the approach which first occurred to me did not work. For the record I'm using the standard win32 function to send messages: PostWindowMessage(UINT nMsg, WPARAM wParam, LPARAM lParam) What does not work: Using static_cast<WPARAM>() does not work since WPARAM is typedef'ed to UINT_PTR and will do a numeric conversion from float to int, effectively truncating the value of the float. Using reinterpret_cast<WPARAM>() does not work since it is meant for use with pointers and fails with a compilation error. I can think of two workarounds at the moment: Using reinterpret_cast in conjunction with the address of operator: float f = 42.0f; ::PostWindowMessage(WM_SOME_MESSAGE, *reinterpret_cast<WPARAM*>(&f), 0); Using an union: union { WPARAM wParam, float f }; f = 42.0f; ::PostWindowMessage(WM_SOME_MESSAGE, wParam, 0); Which of these are preffered? Are there any other more elegant way of accomplishing this?

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  • Getting batch_action functionality in Symfony 1.0

    - by Alex Ciminian
    I'm currently working on a web app written in Symfony. I'm supposed to add an "export to CSV" feature in the backend/administration part of the app for some modules. In the list view, there should be an "Export" button which should provide the user with a csv file of the elements that are displayed (considering filtering criteria). I've created a method in the actions class of the module that takes a comma separated list of ids and generates the CSV, but I'm not really sure how to add the link to it in the view. The problem is that the view doesn't exist anywhere, it's generated on the fly from the data in the generator.yml configuration file. I've posted the relevant part of the file below. I'm new to Symfony, so any help would be appreciated :). Thanks, Alex Update list: display: [id, =name, indemn, _status, _participants, _approved_, created_at] title: Lista actiuni object_actions: _edit: ~ _delete: ~ actions: _create: ~ export_csv: name: Export to CSV action: CSVExport params: id=csvActionSubmit filters: [name, county_id, _status_filter, activity_id] fields: id: name: Nr. crt. ... Thanks to your advice, I've managed to add a button that is linked to my action. The problem is that I also need to send some parameters to the action, because I may not want all the elements - filters may have been used. Unfortunately, the project is using Symfony 1.0, which doesn't support batch_actions. Currently, I'm working around this with Javascript (I parse the DOM to get the numeric ids (from the display table) and then build the link for the button. I really think there could be a better way for this.

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  • Median calculation in ActionScript 3

    - by Gabor Kako
    I have a number array and I'd like to calculate the median. When the array is odd, the calculation is OK, when it's even strange number comes up. private var numbers:String = "2,5,3,4,6,1"; private var array:Array = numbers.split(","); private function getMedian(array:Array):Number { var sortnums:Array = array.sort(Array.NUMERIC); var length:Number = sortnums.length; var mid1:Number; var mid2:Number; var median:Number; if(length % 2 == 0){ mid1 = length / 2; trace("mid1: "+mid1); mid2= ((length - 1) / 2)-0.5; trace("mid2: "+mid2); trace ("mid1: "+sortnums[mid1]+", mid2: "+sortnums[mid2]); median = (sortnums[mid1] + sortnums[mid2]) / 2; }else{ mid1 = (length / 2)-0.5 median = sortnums[mid1] } trace (median); return median; } The result is 21.5, but should be 3.5 mid1 and mid2 are a position in the array. Could somebody help?

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  • Help with MySQL query... Need help ordering a group of rows

    - by user156814
    I can tell it best by explaining the query I have, and what I need. I need to be able to get a group of items from the database, grouped by category, manufacturer, and year made. The groupings need to be sorted based on total amount of items within the group. This part is done with the query below. Secondly, I need to be able to show an image of the most expensive item out of the group, which is why I use MAX(items.current_price). I thought MAX() gets the ENTIRE row corresponding to the largest column value. I was wrong, as MAX only gets the numeric value of the largest price. So the query doesnt work well for that. SELECT items.id, items.year, items.manufacturer, COUNT(items.id) AS total, MAX(items.current_price) AS price, items.gallery_url, FROM ebay AS items WHERE items.primary_category_id = 213 AND items.year <> '' AND items.manufacturer <> '' AND items.bad_item <> 1 GROUP BY items.primary_category_id, items.manufacturer, items.year ORDER BY total DESC, price ASC LIMIT 10 if that doesnt explain it well, the results should be something like this id 10548 year 1989 manufacturer bowman total 451 price 8500.00 (The price of the most expensive item in the table/ not the price of item 10548) gallery_url http://ebay.xxxxx (The image of item 10548) A little help please. Thanks

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  • Optimizing this "Boundarize" method for Numerics in Ruby

    - by mstksg
    I'm extending Numerics with a method I call "Boundarize" for lack of better name; I'm sure there are actually real names for this. But its basic purpose is to reset a given point to be within a boundary. That is, "wrapping" a point around the boundary; if the area is betweeon 0 and 100, if the point goes to -1, -1.boundarize(0,100) = 99 (going one too far to the negative "wraps" the point around to one from the max). 102.boundarize(0,100) = 2 It's a very simple function to implement; when the number is below the minimum, simply add (max-min) until it's in the boundary. If the number is above the maximum, simply subtract (max-min) until it's in the boundary. One thing I also need to account for is that, there are cases where I don't want to include the minimum in the range, and cases where I don't want to include the maximum in the range. This is specified as an argument. However, I fear that my current implementation is horribly, terribly, grossly inefficient. And because every time something moves on the screen, it has to re-run this, this is one of the bottlenecks of my application. Anyone have any ideas? module Boundarizer def boundarize min=0,max=1,allow_min=true,allow_max=false raise "Improper boundaries #{min}/#{max}" if min >= max new_num = self if allow_min while new_num < min new_num += (max-min) end else while new_num <= min new_num += (max-min) end end if allow_max while new_num > max new_num -= (max-min) end else while new_num >= max new_num -= (max-min) end end return new_num end end class Numeric include Boundarizer end

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  • Help! Getting an error copying the data from one column to the same column in a similar recordset..

    - by Mike D
    I have a routine which reads one recordset, and adds/updates rows in a similar recordset. The routine starts off by copying the columns to a new recordset: Here's the code for creating the new recordset.. For X = 1 To aRS.Fields.Count mRS.Fields.Append aRS.Fields(X - 1).Name, aRS.Fields(X - 1).Type, aRS.Fields(X - _ 1).DefinedSize, aRS.Fields(X - 1).Attributes Next X Pretty straight forward. Notice the copying of the name, Type, DefinedSize & Attributes... Further down in the code, (and there's nothing that modifies any of the columns between.. ) I'm copying the values of a row to a row in the new recordset as such: For C = 1 To aRS.Fields.Count mRS.Fields(C - 1) = aRS.Fields(C - 1) Next C When it gets to the last column which is a numeric, it craps with the "Mutliple-Step Operation Generated an error" message. I know that MS says this is an error generated by the provider, which in this case is ADO 2.8. There is no open connect to the DB at this point in time either. I'm pulling what little hair I have left over this one... (and I don't really care at this point that the column index is 'X' in one loop & 'C' in the other... I'll change it later when I get the real problem fixed...)

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  • Passing list of values to django view via jQuery ajax call

    - by finspin
    I'm trying to pass a list of numeric values (ids) from one web page to another with jQuery ajax call. I can't figure out how to pass and read all the values in the list. I can successfully post and read 1 value but not multiple values. Here is what I have so far: jQuery: var postUrl = "http://localhost:8000/ingredients/"; $('li').click(function(){ values = [1, 2]; $.ajax({ url: postUrl, type: 'POST', data: {'terid': values}, traditional: true, dataType: 'html', success: function(result){ $('#ingredients').append(result); } }); }); /ingredients/ view: def ingredients(request): if request.is_ajax(): ourid = request.POST.get('terid', False) ingredients = Ingredience.objects.filter(food__id__in=ourid) t = get_template('ingredients.html') html = t.render(Context({'ingredients': ingredients,})) return HttpResponse(html) else: html = '<p>This is not ajax</p>' return HttpResponse(html) With Firebug I can see that POST contains both ids but probably in the wrong format (terid=1&terid=2). So my ingredients view picks up only terid=2. What am I doing wrong? EDIT: To clarify, I need the ourid variable pass values [1, 2] to the filter in the ingredients view.

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  • JavaScript: why `null == 0` is false?

    - by lemonedo
    I had to write a routine that increments the value of a variable by 1 if it is a number, or assigns 0 to the variable if it is not a number. The variable can be incremented by the expression, or be assigned null. No other write access to the variable is allowed. So, the variable can be in three states: it is 0, a positive integer, or null. My first implementation was: v >= 0 ? v += 1 : v = 0 (Yes, I admit that v === null ? v = 0 : v += 1 is the exact solution, but I wanted to be concise then.) It failed since null >= 0 is true. I was confused, since if a value is not a number, an numeric expression involving it must be false always. Then I found that null is like 0, since null + 1 == 1, 1 / null == Infinity, Math.pow(2.718281828, null) == 1, ... Strangely enough, however, null == 0 is evaluated to false. I guess null is the only value that makes the following expression false: (v == 0) === (v >= 0 && v <= 0) So why null is so special in JavaScript?

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  • Missing tables on Scaffold Dynamic Data page

    - by Ben Amada
    I created a Linq-to-SQL DBML for the first time. I dragged and dropped all my tables over to the designer. The tables all appear in the designer.cs file. In Global.asax, I also have model.RegisterContext() with the ScaffoldAllTables = true option. The routes are also setup. I can pull up the Scaffolding page, but there's at least one table that is missing that I'm trying to get to show up. This missing table has a relationship with a child table that references it. The child table appears. When viewing data for the child table, the column that references the missing/parent table shows the numeric PK int value, rather than showing the "name". So instead of showing "Cars" it shows 1, and instead of showing "Planes" it shows 2, etc. There's another table in the DB that has the same type of structure as the missing table, and it is correctly appearing in the scaffolded tables. For this missing table, I've tried explicitly adding the ScaffoldTable attribute to no avail. Does anyone know what would cause a table like this to not appear in the list Scaffolded tables? Thanks very much.

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  • What is the nicest way to parse this in C++ ?

    - by ereOn
    Hi, In my program, I have a list of "server address" in the following format: host[:port] The brackets here, indicate that the port is optional. host can be a hostname, an IPv4 or IPv6 address. port, if present can be a numeric port number or a service string (like: "http" or "ssh"). If port is present and host is an IPv6 address, host must be in "bracket-enclosed" notation (Example: [::1]) Here are some valid examples: localhost localhost:11211 127.0.0.1:http [::1]:11211 ::1 [::1] And an invalid example: ::1:80 // Invalid: Is this the IPv6 address ::1:80 and a default port, or the IPv6 address ::1 and the port 80 ? ::1:http // This is not ambigous, but for simplicity sake, let's consider this is forbidden as well. My goal is to separate such entries in two parts (obviously host and port). I don't care if either the host or port are invalid as long as they don't contain a : (290.234.34.34.5 is ok for host, it will be rejected in the next process); I just want to separate the two parts, or if there is no port part, to know it somehow. I tried to do something with std::stringstream but everything I come up to seems hacky and not really elegant. How would you do this in C++ ? I don't mind answers in C but C++ is prefered. Any boost solution is welcome as well. Thank you.

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  • jQuery form zip code to state function

    - by Dakota R.
    I'm trying to convert a preexisting javascript function into a jQuery function. The function comes from http://javascript.internet.com/forms/zip-to-state.html and aims to convert a user-entered zip code into a state. I'm using jQuery 1.3.2, with all the necessary plugins, but I'm not very familiar with jQuery syntax and how to convert this from plain ol' Javascript syntax. The setState function takes two parameters, the zip code element and the state element, so I'm trying to do something like this: $('$zip_code').change( function () { setState($(this), $('#state')); }); Any thoughts on this syntax? Thanks, Dakota function getState(zip) { if ((parseInt(zipString.substr(zip / 4, 1), 16) & Math.pow(2, zip % 4)) && (zip.length == 5)) for (var i = 0; i < stateRange.length; i += 7) if (zip <= 1 * stateRange.substr(i, 5)) return stateRange.substr(i + 5, 2); return null; } function setState(txtZip, optionBox) { if (txtZip.value.length != 5 || isNaN(txtZip.value / 4)) { optionBox.options[0].selected = true; alert("Please enter a 5 digit, numeric zip code."); return; } var state = getState(txtZip.value); for (var i = 0; i < optionBox.options.length; i++) if (optionBox.options[i].value == state) return optionBox.options[i].selected = true; for (var i = 0; i < optionBox.options.length; i++) if (optionBox.options[i].value == "XX") return optionBox.options[i].selected = true; }

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  • Check if date is allowed weekday in php?

    - by moogeek
    Hello! I'm stuck with a problem how to check if a specific date is within allowed weekdays array in php. For example, function dateIsAllowedWeekday($_date,$_allowed) { if ((isDate($_date)) && (($_allowed!="null") && ($_allowed!=null))){ $allowed_weekdays=json_decode($_allowed); $weekdays=array(); foreach($allowed_weekdays as $wd){ $weekday=date("l",date("w",strtotime($wd))); array_push($weekdays,$weekday); } if(in_array(date("l",strtotime($_date)),$weekdays)){return TRUE;} else {return FALSE;} } else {return FALSE;} } ///////////////////////////// $date="21.05.2010"; $wd="[0,1,2]"; if(dateIsAllowedWeekday($date,$wd)){echo "$date is within $wd weekday values!";} else{echo "$date isn't within $wd weekday values!"} I have input dates formatted as "d.m.Y" and an array returned from database with weekday numbers (formatted as 'Numeric representation of the day of the week') like [0,1,2] - (Sunday,Monday,Tuesday). The returned string from database can be "null", so i check it too. Them, the isDate function checks whether date is a date and it is ok. I want to check if my date, for example 21.05.2010 is an allowed weekday in this array. My function always returns TRUE and somehow weekday is always 'Thursday' and i don't know why... Is there any other ways to check this or what can be my error in the code above? thx

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  • Do I need to Salt and Hash a randomly generated token?

    - by wag2639
    I'm using Adam Griffiths's Authentication Library for CodeIgniter and I'm tweaking the usermodel. I came across a generate function that he uses to generate tokens. His preferred approach is to reference a value from random.org but I considered that superfluous. I'm using his fall back approach of randomly generating a 20 character long string: $length = 20; $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; $token = ''; for ($i = 0; $i < $length; $i++) { $token .= $characters[mt_rand(0, strlen($characters)-1)]; } He then hashes this token using a salt (I'm combing code from different functions) sha1($this->CI->config->item('encryption_key').$str); I was wondering if theres any reason to to run the token through the salted hash? I've read that simply randomly generating strings was a naive way of making random passwords but is the sh1 hash and salt necessary? Note: I got my encryption_key from https://www.grc.com/passwords.htm (63 random alpha-numeric)

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  • How can I solve the Log Pile wooden puzzle with a computer program?

    - by craig1410
    Can anyone suggest how to solve the Log Pile wooden puzzle using a computer program? See here to visualise the puzzle: http://www.puzzlethis.co.uk/products/madcow/the_log_pile.htm The picture only shows some of the pieces. The full set of 10 pieces are configured as follows with 1 representing a peg, -1 representing a hole and 0 representing neither a peg nor a hole. -1,1,0,-1,0 1,0,1,0,0 1,-1,1,0,0 -1,-1,0,0,-1 -1,1,0,1,0 0,1,0,0,1 1,0,-1,0,-1 0,-1,0,1,0 0,0,-1,1,-1 1,0,-1,0,0 The pieces can be interlocked in two layers of 5 pieces each with the top layer at 90 degrees to the bottom layer as shown in the above link. I have already created a solution to this problem myself using Java but I feel that it was a clumsy solution and I am interested to see some more sophisticated solutions. Feel free to either suggest a general approach or to provide a working program in the language of your choice. My approach was to use the numeric notation above to create an array of "Logs". I then used a combination/permutation generator to try all possible arrangements of the Logs until a solution was found where all the intersections equated to zero (ie. Peg to Hole, Hole to Peg or Blank to Blank). I used some speed-ups to detect the first failed intersection for a given permutation and move on to the next permutation. I hope you find this as interesting as I have. Thanks, Craig.

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  • AWK: compare apache dates without using regular expression

    - by smallmeans
    I'm writing a loganalysis application and wanted to grab apache log records between two certain dates. Assume that a date is formated as such: 22/Dec/2009:00:19 (day/month/year:hour:minute) Currently, I'm using a regular expression to replace the month name with its numeric value, remove the separators, so the above date is converted to: 221220090019 making a date comparison trivial.. but.. Running a regex on each record for large files, say, one containing a quarter million records, is extremely costly.. is there any other method not involving regex substitution? Thanks in advance Edit: here's the function doing the convertion/comparison function dateInRange(t, from, to) { sub(/[[]/, "", t); split(t, a, "[/:]"); match("JanFebMarAprMayJunJulAugSepOctNovDec", a[2]); a[2] = sprintf("%02d", (RSTART + 2) / 3); s = a[3] a[2] a[1] a[4] a[5]; return s >= from && s <= to; } "from" and "to" are the intervals in the aforementioned format, and "t" is the raw apache log date/time field (e.g [22/Dec/2009:00:19:36)

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  • Spreadsheet_Excel_Writer data output is damaged

    - by dr3w
    I use Spreadsheet_Excel_Writer to generate .xls file and it works fine until I have to deal with a large amount of data. On certain stage it just writes some nonsense chars and quits filling certain columns. However some columns are field up to the end (generally numeric data) I'm not quite sure how the xls document is formed: row by row, or col by col... Also it is obviously not an error in a string, because when i cut out some data, the error appears a little bit further. I think there is no need in all of my code here are some essentials $filename = 'file.xls'; $workbook = & new Spreadsheet_Excel_Writer(); $workbook->setVersion(8); $contents =& $workbook->addWorksheet('Logistics'); $contents->setInputEncoding('UTF-8'); $workbook->send($filename); //here is the part where I write data down $contents->write(0, 0, 'Field A'); $contents->write(0, 1, 'Field B'); $contents->write(0, 2, 'Field C'); $ROW=1; foreach($ordersArr as $key=>$val){ $contents->write($ROW, 0, $val['a']); $contents->write($ROW, 1, $val['b']); $contents->write($ROW, 2, $val['c']); $ROW++; } $workbook->close();

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  • row number over text column sort

    - by Marty Trenouth
    I'm having problems with dynamic sorting using ROW Number in SQL Server. I have it working but it's throwing errors on non numeric fields. What do I need to change to get sorts with Alpha Working??? ID Description 5 Test 6 Desert 3 A evil Ive got a Sql Prodcedure CREATE PROCEDURE [CRUDS].[MyTable_Search] -- Add the parameters for the stored procedure here -- Full Parameter List @ID int = NULL, @Description nvarchar(256) = NULL, @StartIndex int = 0, @Count int = null, @Order varchar(128) = 'ID asc' AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON; -- Insert statements for procedure here Select * from ( Select ROW_NUMBER() OVER (Order By case when @Order = 'ID asc' then [TableName].ID when @Order = 'Description asc' then [TableName].Description end asc, case when @Order = 'ID desc' then [TableName].ID when @Order = 'Description desc' then [TableName].Description end desc ) as row, [TableName].* from [TableName] where (@ID IS NULL OR [TableName].ID = @ID) AND (@Description IS NULL OR [TableName].Description = @Description) ) as a where row > @StartIndex and (@Count is null or row <= @StartIndex + @Count) order by case when @Order = 'ID asc' then a.ID when @Order = 'Description asc' then a.Description end asc, case when @Order = 'ID desc' then a.ID when @Order = 'Description desc' then a.Description end desc END

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  • C++: defining maximum/minimum limits for a class

    - by Luis
    Basically what the title says... I have created a class that models time slots in a variable-granularity daily schedule (where for example the first time slot is 30 minutes, but the second time slot can be 40 minutes); the first available slot starts at (a value comparable to) 1. What I want to do now is to define somehow the maximum and minimum allowable values that this class takes and I have two practical questions in order to do so: 1.- does it make sense to define absolute minimum and maximum in such a way for a custom class? Or better, does it suffice that a value always compares as lower-than any other possible value of the type, given the class's defined relational operators, to be defined the min? (and analogusly for the max) 2.- assuming the previous question has an answer modeled after "yes" (or "yes but ..."), how do I define such max/min? I know that there is std::numeric_limits<> but from what I read it is intended for "numeric types". Do I interpret that as meaning "represented as a number" or can I make a broader assumption like "represented with numbers" or "having a correspondence to integers"? After all, it would make sense to define the minimum and maximum for a date class, and maybe for a dictionary class, but numeric_limits may not be intended for those uses (I don't have much experience with it). Plus, numeric_limits has a lot of extra members and information that I don't know what to make with. If I don't use numeric_limits, what other well-known / widely-used mechanism does C++ offer to indicate the available range of values for a class?

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  • How does does ifstream eof() work?

    - by Chan
    Hello everyone, #include <vector> #include <list> #include <map> #include <set> #include <deque> #include <stack> #include <bitset> #include <algorithm> #include <functional> #include <numeric> #include <utility> #include <sstream> #include <iostream> #include <iomanip> #include <cstdio> #include <cmath> #include <cstdlib> #include <ctime> #include <cctype> #include <fstream> using namespace std; int main() { fstream inf( "ex.txt", ios::in ); while( !inf.eof() ) { std::cout << inf.get() << "\n"; } inf.close(); inf.clear(); inf.open( "ex.txt", ios::in ); char c; while( inf >> c ) { std::cout << c << "\n"; } return 0; } I'm really confused about eof() function. Suppose my ex.txt's content is: abc It always reads an extra character and show -1. when reading using eof()? But the inf c gave the correct output which was 'abc'? Can anyone help me explain this? Best regards, Chan Nguyen

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  • Problem in DataBinding an Enum using dictionary approach to a combobox in WPF.

    - by Ashish Ashu
    I have a Dictionary which is binded to a combobox. I have used dictionary to provide spaces in enum. public enum Option {Enter_Value, Select_Value}; Dictionary<Option,string> Options; <ComboBox x:Name="optionComboBox" SelectionChanged="optionComboBox_SelectionChanged" SelectedValuePath="Key" DisplayMemberPath="Value" SelectedItem="{Binding Path = SelectedOption}" ItemsSource="{Binding Path = Options}" /> This works fine. My queries: 1. I am not able to set the initial value to a combo box. In above XAML snippet the line SelectedItem="{Binding Path = SelectedOption}" is not working. I have declared SelectOption in my viewmodel. This is of type string and I have intialized this string value in my view model as below: SelectedOption = Options[Options.Enter_Value].ToString(); 2. The combobox is binded to datadictionary which have two options first is "Enter_value" and second is "Select_value" which is actually Option enum. Based on the Option enum value I want to perform different action. For example if option is equal to option.Enter_value then Combo box becomes editable and user can enter the numeric value in it. if option is equal to option.Select_value value then the value comes from the database and the combo box becomes read only and shows the fetched value from the database. Please Help!!

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  • How to refer to enum values inside nhibernate formula mapping specification?

    - by mark
    Dear ladies and sirs. I have two entities types: RunContainer parent entity type Run child entity type Run has a property Status, which is of type RunStatus, like so: public enum RunStatus { Created, Starting, // ... } public class Run { public int ContainerId { get; private set; } // ... public RunStatus Status { get; private set; } } RunContainer has a calculated property ActiveRunCount, like so: public class RunContainer { public int Id { get; private set; } // ... public int ActiveRunCount { get; private set; } } In the mapping for the RunContainer.ActiveRunCount property, I use the formula specification like so: <property name="ActiveRunCount" formula="(select count(r.Id) from Run r where r.ContainerId = Id and r.Status = 1)"/> My problem is that I refer to the RunStatus enum values in the formula by their respective numeric value, rather than the appropriate symbolic name. Can anyone tell me how can I use the symbolic name instead? Thanks.

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