Search Results

Search found 1806 results on 73 pages for 'numeric precision'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 9/73 | < Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >

  • Multi-Precision Arithmetic on MIPS

    - by Rob
    Hi, I am just trying to implement multi-precision arithmetic on native MIPS. Assume that one 64-bit integer is in register $12 and $13 and another is in registers $14 and $15. The sum is to be placed in registers $10 and $11. The most significant word of the 64-bit integer is found in the even-numbered registers, and the least significant word is found in the odd-numbered registers. On the internet, it said, this is the shortest possible implementation. addu $11, $13, $15 # add least significant word sltu $10, $11, $15 # set carry-in bit addu $10, $10, $12 # add in first most significant word addu $10, $10, $14 # add in second most significant word I just wanna double check that I understand correctly. The sltu checks if the sum of the two least significant words is smaller or equal than one of the operands. If this is the case, than did a carry occur, is this right? To check if there occured a carry when adding the two most significant words and store the result in $9 I have to do: sltu $9, $10, $12 # set carry-in bit Does this make any sense?

    Read the article

  • Retain numerical precision in an R data frame?

    - by David
    When I create a dataframe from numeric vectors, R seems to truncate the value below the precision that I require in my analysis: data.frame(x=0.99999996) returns 1 (see update 1) I am stuck when fitting spline(x,y) and two of the x values are set to 1 due to rounding while y changes. I could hack around this but I would prefer to use a standard solution if available. example Here is an example data set d <- data.frame(x = c(0.668732936336141, 0.95351462456867, 0.994620622127435, 0.999602102672081, 0.999987126195509, 0.999999955814133, 0.999999999999966), y = c(38.3026509783688, 11.5895099585560, 10.0443344234229, 9.86152339768516, 9.84461434575695, 9.81648333804257, 9.83306725758297)) The following solution works, but I would prefer something that is less subjective: plot(d$x, d$y, ylim=c(0,50)) lines(spline(d$x, d$y),col='grey') #bad fit lines(spline(d[-c(4:6),]$x, d[-c(4:6),]$y),col='red') #reasonable fit Update 1 Since posting this question, I realize that this will return 1 even though the data frame still contains the original value, e.g. > dput(data.frame(x=0.99999999996)) returns structure(list(x = 0.99999999996), .Names = "x", row.names = c(NA, -1L), class = "data.frame") Update 2 After using dput to post this example data set, and some pointers from Dirk, I can see that the problem is not in the truncation of the x values but the limits of the numerical errors in the model that I have used to calculate y. This justifies dropping a few of the equivalent data points (as in the example red line).

    Read the article

  • Fastest way to remove non-numeric characters from a VARCHAR in SQL Server

    - by Dan Herbert
    I'm writing an import utility that is using phone numbers as a unique key within the import. I need to check that the phone number does not already exist in my DB. The problem is that phone numbers in the DB could have things like dashes and parenthesis and possibly other things. I wrote a function to remove these things, the problem is that it is slow and with thousands of records in my DB and thousands of records to import at once, this process can be unacceptably slow. I've already made the phone number column an index. I tried using the script from this post: http://stackoverflow.com/questions/52315/t-sql-trim-nbsp-and-other-non-alphanumeric-characters But that didn't speed it up any. Is there a faster way to remove non-numeric characters? Something that can perform well when 10,000 to 100,000 records have to be compared. Whatever is done needs to perform fast. Update Given what people responded with, I think I'm going to have to clean the fields before I run the import utility. To answer the question of what I'm writing the import utility in, it is a C# app. I'm comparing BIGINT to BIGINT now, with no need to alter DB data and I'm still taking a performance hit with a very small set of data (about 2000 records). Could comparing BIGINT to BIGINT be slowing things down? I've optimized the code side of my app as much as I can (removed regexes, removed unneccessary DB calls). Although I can't isolate SQL as the source of the problem anymore, I still feel like it is.

    Read the article

  • Grouping Collection seperating numeric 5 from String "5"

    - by invertedSpear
    BackGround: I have an advanced data grid. The data provider for this ADG is an ArrayCollection. There is a grouping collection on an ID field of this AC. Example of a couple items within this AC the AC var name is "arcTemplates": (mx.collections::ArrayCollection)#0 filterFunction = (null) length = 69 list = (mx.collections::ArrayList)#1 length = 69 source = (Array)#2 [0] (Object)#3 abbreviation = "sore-throat" insertDate = "11/16/2009" name = "sore throat" templateID = 234 templateType = "New Problem" templateTypeID = 1 [32] (Object)#35 abbreviation = 123 insertDate = "03/08/2010" name = 123 templateID = 297 templateType = "New Problem" templateTypeID = 1 [55] (Object)#58 abbreviation = 1234 insertDate = "11/16/2009" name = 1234 templateID = 227 templateType = "Exam" templateTypeID = 5 [56] (Object)#59 abbreviation = "breast only" insertDate = "03/15/2005" name = "breast exam" templateID = 195 templateType = "Exam" templateTypeID = 5 Example of Flex code leading to the Grouping: <mx:AdvancedDataGrid displayItemsExpanded="true" id="gridTemplates"> <mx:dataProvider> <mx:GroupingCollection id="gc" source="{arcTemplates}"> <mx:Grouping > <mx:GroupingField name="templateTypeID" compareFunction="gcSort"> GC sort function: public function gcSort(a:Object, b:Object):int{ return ObjectUtil.stringCompare(String(a.templateTypeID + a.name).toLowerCase(), String(b.templateTypeID + b.name).toLowerCase()); } Problem: In my AC example there are a few items, items 0, 32 and 56 properly sort and group to their templateTypeID, but item 55 does something weird. It seems to sort/group on the numeric 5 instead of the string "5". Gets stranger. If I change the name property to contain text (so 1234x) it then correctly sorts/groups to the string "5" Question: What is going on here and how do I fix it?

    Read the article

  • Regex for removing certain variable numeric values from some text

    - by stephemurdoch
    I want to substitute all 4 instances of the number 300 from the code below, with 470. <div> <object width="300" height="300"> <embed src="link-removed" width="300" height="300"></embed> </object> <p> <a href="another-link">link</a> </p> </div> The width and height of the code being pasted might not always be 300 by 300. So I figure I probably need a regular expression that subs any numeric value that follows the strings "width=" and "height=", whilst remembering to account for the quotations marks that surround the number. Can anyone tell me if that's the best way, and if so, what would be the best regex? In case it matters, the code being pasted is stored as "text" in the db rather than as a string, as it's quite lengthy (i've removed a few hundred chars from what you see pasted here)...

    Read the article

  • how to determine if a character vector is a valid numeric or integer vector

    - by Andrew Barr
    I am trying to turn a nested list structure into a dataframe. The list looks similar to the following (it is serialized data from parsed JSON read in using the httr package). myList <- list(object1 = list(w=1, x=list(y=0.1, z="cat")), object2 = list(w=2, x=list(y=0.2, z="dog"))) unlist(myList) does a great job of recursively flattening the list, and I can then use lapply to flatten all the objects nicely. flatList <- lapply(myList, FUN= function(object) {return(as.data.frame(rbind(unlist(object))))}) And finally, I can button it up using plyr::rbind.fill myDF <- do.call(plyr::rbind.fill, flatList) str(myDF) #'data.frame': 2 obs. of 3 variables: #$ w : Factor w/ 2 levels "1","2": 1 2 #$ x.y: Factor w/ 2 levels "0.1","0.2": 1 2 #$ x.z: Factor w/ 2 levels "cat","dog": 1 2 The problem is that w and x.y are now being interpreted as character vectors, which by default get parsed as factors in the dataframe. I believe that unlist() is the culprit, but I can't figure out another way to recursively flatten the list structure. A workaround would be to post-process the dataframe, and assign data types then. What is the best way to determine if a vector is a valid numeric or integer vector?

    Read the article

  • error: expected ',' or '...' before numeric constant

    - by goldfrapp04
    Just a Qt Gui Application with QDialog as the Base Class, the simplest type you can expect. I've programmed on Qt for several times but this is the first time I meet this problem... I've added minimal code to the program, and here's the code in dialog.h (which is mostly automatically generated) #ifndef DIALOG_H #define DIALOG_H #include <QDialog> #include <QPixmap> #include "bmp.h" namespace Ui { class Dialog; } class Dialog : public QDialog { Q_OBJECT public: explicit Dialog(QWidget *parent = 0); ~Dialog(); private slots: void on_openButton_clicked(); private: Ui::Dialog *ui; BMP srcImage; QImage compressedImage[3]; }; #endif // DIALOG_H While I edit, the "public:" is underlined and says "unexpected token '('". When I try to build the program, it says in the line "Q_OBJECT", "error: expected ',' or '...' before numeric constant". I'm sure I've defined nothing related to it (to be exact, I defined an N and an n in file bmp.h, both are int). Any idea of what's wrong here? Thanks.

    Read the article

  • Random Alpha numeric generator

    - by AAA
    Hi, I want to give our users in the database a unique alpha-numeric id. I am using the code below, will this always generate a unique id? Below is the old and updated version of the code: New php: // Generate Guid function NewGuid() { $s = strtoupper(md5(uniqid("something",true))); $guidText = substr($s,0,8) . '-' . substr($s,8,4) . '-' . substr($s,12,4). '-' . substr($s,16,4). '-' . substr($s,20); return $guidText; } // End Generate Guid $Guid = NewGuid(); echo $Guid; echo "<br><br><br>"; Old PHP: // Generate Guid function NewGuid() { $s = strtoupper(md5(uniqid("something",true))); $guidText = substr($s,0,8) . '-' . substr($s,8,4) . '-' . substr($s,12,4). '-' . substr($s,16,4). '-' . substr($s,20); return $guidText; } // End Generate Guid $Guid = NewGuid(); echo $Guid; echo "<br><br><br>"; Will this first code guarantee uniqueness?

    Read the article

  • MIPS: removing non alpha-numeric characters from a string

    - by Kron
    I'm in the process of writing a program in MIPS that will determine whether or not a user entered string is a palindrome. It has three subroutines which are under construction. Here is the main block of code, subroutines to follow with relevant info: .data Buffer: .asciiz " " # 80 bytes in Buffer intro: .asciiz "Hello, please enter a string of up to 80 characters. I will then tell you if that string was a palindrome!" .text main: li $v0, 4 # print_string call number la $a0, intro # pointer to string in memory syscall li $v0, 8 #syscall code for reading string la $a0, Buffer #save read string into buffer li $a1, 80 #string is 80 bytes long syscall li $s0, 0 #i = 0 li $t0, 80 #max for i to reach la $a0, Buffer jal stripNonAlpha li $v0, 4 # print_string call number la $a0, Buffer # pointer to string in memory syscall li $s0, 0 jal findEnd jal toUpperCase li $v0, 4 # print_string call number la $a0, Buffer # pointer to string in memory syscall Firstly, it's supposed to remove all non alpha-numeric characters from the string before hand, but when it encounters a character designated for removal, all characters after that are removed. stripNonAlpha: beq $s0, $t0, stripEnd #if i = 80 end add $t4, $s0, $a0 #address of Buffer[i] in $t4 lb $s1, 0($t4) #load value of Buffer[i] addi $s0, $s0, 1 #i = i + 1 slti $t1, $s1, 48 #if ascii code is less than 48 bne $t1, $zero, strip #remove ascii character slti $t1, $s1, 58 #if ascii code is greater than 57 #and slti $t2, $s1, 65 #if ascii code is less than 65 slt $t3, $t1, $t2 bne $t3, $zero, strip #remove ascii character slti $t1, $s1, 91 #if ascii code is greater than 90 #and slti $t2, $s1, 97 #if ascii code is less than 97 slt $t3, $t1, $t2 bne $t3, $zero, strip #remove ascii character slti $t1, $s1, 123 #if ascii character is greater than 122 beq $t1, $zero, strip #remove ascii character j stripNonAlpha #go to stripNonAlpha strip: #add $t5, $s0, $a0 #address of Buffer[i] in $t5 sb $0, 0($t4) #Buffer[i] = 0 #addi $s0, $s0, 1 #i = i + 1 j stripNonAlpha #go to stripNonAlpha stripEnd: la $a0, Buffer #save modified string into buffer jr $ra #return Secondly, it is supposed to convert all lowercase characters to uppercase. toUpperCase: beq $s0, $s2, upperEnd add $t4, $s0, $a0 lb $s1, 0($t4) addi $s1, $s1, 1 slti $t1, $s1, 97 #beq $t1, $zero, upper slti $t2, $s1, 123 slt $t3, $t1, $t2 bne $t1, $zero, upper j toUpperCase upper: add $t5, $s0, $a0 addi $t6, $t6, -32 sb $t6, 0($t5) j toUpperCase upperEnd: la $a0, Buffer jr $ra The final subroutine, which checks if the string is a palindrome isn't anywhere near complete at the moment. I'm having trouble finding the end of the string because I'm not sure what PC-SPIM uses as the carriage return character. Any help is appreciated, I have the feeling most of my problems result from something silly and stupid so feel free to point out anything, no matter how small.

    Read the article

  • J2ME TextField Exception

    - by Bob
    When I instantiate a textField, I have a number in it that I want to be the default text. The problem is, I can't seem to be able to place that value into the textfield without getting an error. The strange thing about it is that the same TextField is what I use to set the value of the variable containing the number. TextField myTF = new TextField("Number", value, 10, TextField.NUMERIC); When I run this code, I receive an exception stating that value doesn't match the constraints of TextField.NUMERIC. However, when I check the vale of the value of the variable, I get the following output: value = 1234567890 value.length() = 10 The value is set by the same TextField, saved to the phone that I am working on, and when loaded from the phone's settings, throws an exception.

    Read the article

  • Unique Alpha numeric generator

    - by AAA
    Hi, I want to give our users in the database a unique alpha-numeric id. I am using the code below, will this always generate a unique id? Below is the updated version of the code: old php: // Generate Guid function NewGuid() { $s = strtoupper(md5(uniqid(rand(),true))); $guidText = substr($s,0,8) . '-' . substr($s,8,4) . '-' . substr($s,12,4). '-' . substr($s,16,4). '-' . substr($s,20); return $guidText; } // End Generate Guid $Guid = NewGuid(); echo $Guid; echo "<br><br><br>"; New PHP: // Generate Guid function NewGuid() { $s = strtoupper(uniqid("something",true)); $guidText = substr($s,0,8) . '-' . substr($s,8,4) . '-' . substr($s,12,4). '-' . substr($s,16,4). '-' . substr($s,20); return $guidText; } // End Generate Guid $Guid = NewGuid(); echo $Guid; echo "<br><br><br>"; Will the second (new php) code guarantee 100% uniqueness. Final code: PHP // Generate Guid function NewGuid() { $s = strtoupper(uniqid(rand(),true)); $guidText = substr($s,0,8) . '-' . substr($s,8,4) . '-' . substr($s,12,4). '-' . substr($s,16,4). '-' . substr($s,20); return $guidText; } // End Generate Guid $Guid = NewGuid(); echo $Guid; $alphabet = '123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ'; function base_encode($num, $alphabet) { $base_count = strlen($alphabet); $encoded = ''; while ($num >= $base_count) { $div = $num/$base_count; $mod = ($num-($base_count*intval($div))); $encoded = $alphabet[$mod] . $encoded; $num = intval($div); } if ($num) $encoded = $alphabet[$num] . $encoded; return $encoded; } function base_decode($num, $alphabet) { $decoded = 0; $multi = 1; while (strlen($num) > 0) { $digit = $num[strlen($num)-1]; $decoded += $multi * strpos($alphabet, $digit); $multi = $multi * strlen($alphabet); $num = substr($num, 0, -1); } return $decoded; } echo base_encode($Guid, $alphabet); } So for more stronger uniqueness, i am using the $Guid as the key generator. That should be ok right?

    Read the article

  • Delphi 2009 - Strip non alpha numeric from string

    - by Brad
    I've got the following code, and need to strip all non alpha numeric characters. It's not working in delphi 2009 ` unit Unit2; //Used information from // http://stackoverflow.com/questions/574603/what-is-the-fastest-way-of-stripping-non-alphanumeric-characters-from-a-string-in interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; Type TExplodeArray = Array Of String; TForm2 = class(TForm) Memo1: TMemo; ListBox1: TListBox; Button1: TButton; procedure Button1Click(Sender: TObject); private { Private declarations } public { Public declarations } Function Explode ( Const cSeparator, vString : String ) : TExplodeArray; Function Implode ( Const cSeparator : String; Const cArray : TExplodeArray ) : String; Function StripHTML ( S : String ) : String; function allwords(data:string):integer; end; var Form2: TForm2; allword, allphrase: TExplodeArray; implementation {$R *.dfm} Function TForm2.StripHTML ( S : String ) : String; Var TagBegin, TagEnd, TagLength : Integer; Begin TagBegin := Pos ( '<', S ); // search position of first < While ( TagBegin > 0 ) Do Begin // while there is a < in S TagEnd := Pos ( '>', S ); // find the matching > TagLength := TagEnd - TagBegin + 1; Delete ( S, TagBegin, TagLength ); // delete the tag TagBegin := Pos ( '<', S ); // search for next < End; Result := S; // give the result End; Function TForm2.Implode ( Const cSeparator : String; Const cArray : TExplodeArray ) : String; Var i : Integer; Begin Result := ''; For i := 0 To Length ( cArray ) - 1 Do Begin Result := Result + cSeparator + cArray [i]; End; System.Delete ( Result, 1, Length ( cSeparator ) ); End; Function TForm2.Explode ( Const cSeparator, vString : String ) : TExplodeArray; Var i : Integer; S : String; Begin S := vString; SetLength ( Result, 0 ); i := 0; While Pos ( cSeparator, S ) 0 Do Begin SetLength ( Result, Length ( Result ) + 1 ); Result[i] := Copy ( S, 1, Pos ( cSeparator, S ) - 1 ); Inc ( i ); S := Copy ( S, Pos ( cSeparator, S ) + Length ( cSeparator ), Length ( S ) ); End; SetLength ( Result, Length ( Result ) + 1 ); Result[i] := Copy ( S, 1, Length ( S ) ); End; //Copied from JclStrings function StrKeepChars(const S: AnsiString; const Chars: TSysCharSet): AnsiString; var Source, Dest: PChar; begin SetLength(Result, Length(S)); UniqueString(Result); Source := PChar(S); Dest := PChar(Result); while (Source < nil) and (Source^ < #0) do begin if Source^ in Chars then begin Dest^ := Source^; Inc(Dest); end; Inc(Source); end; SetLength(Result, (Longint(Dest) - Longint(PChar(Result))) div SizeOf(AnsiChar)); end; function ReplaceNewlines(const AValue: string): string; var SrcPtr, DestPtr: PChar; begin SrcPtr := PChar(AValue); SetLength(Result, Length(AValue)); DestPtr := PChar(Result); while SrcPtr < {greater than less than} #0 do begin if (SrcPtr[0] = #13) and (SrcPtr[1] = #10) then begin DestPtr[0] := '\'; DestPtr[1] := 't'; Inc(SrcPtr); Inc(DestPtr); end else DestPtr[0] := SrcPtr[0]; Inc(SrcPtr); Inc(DestPtr); end; SetLength(Result, DestPtr - PChar(Result)); end; function StripNonAlphaNumeric(const AValue: string): string; var SrcPtr, DestPtr: PChar; begin SrcPtr := PChar(AValue); SetLength(Result, Length(AValue)); DestPtr := PChar(Result); while SrcPtr < #0 do begin if SrcPtr[0] in ['a'..'z', 'A'..'Z', '0'..'9'] then begin DestPtr[0] := SrcPtr[0]; Inc(DestPtr); end; Inc(SrcPtr); end; SetLength(Result, DestPtr - PChar(Result)); end; function TForm2.allwords(data:string):integer; var i:integer; begin listbox1.Items.add(data); data:= StripHTML ( data ); listbox1.Items.add(data); ////////////////////////////////////////////////////////////// data := StrKeepChars(data, ['A'..'Z', 'a'..'z', '0'..'9']); // Strips out everything data comes back blank in Delphi 2009 ////////////////////////////////////////////////////////////// listbox1.Items.add(data); data := stringreplace(data,' ',' ', [rfReplaceAll, rfIgnoreCase] ); //Replace two spaces with one. listbox1.Items.add(data); allword:= explode(' ',data); { // Converting the following PHP code to Delphi $text = ereg_replace("[^[:alnum:]]", " ", $text); while(strpos($text,' ')!==false) $text = ereg_replace(" ", " ", $text); $text=$string=strtolower($text); $text=explode(" ",$text); return count($text); } for I := 0 to Length(allword) - 1 do listbox1.Items.Add(allword[i]); end; procedure TForm2.Button1Click(Sender: TObject); begin //[^[:alnum:]] allwords(memo1.Text); end; end. ` How else would I go about doing this? Thanks

    Read the article

  • When must arbitrary precision arithmetic functions be used in PHP?

    - by Tjorriemorrie
    My colleague uses the Binary Calculator functions in bandwidth calculations; as much as terrabytes, and with percentage splitting on allocation. His usage of these functions appears correct in order not to lose a byte; although he seems to be using them now for everything. The manual only says: For arbitrary precision mathematics PHP offers the Binary Calculator which supports numbers of any size and precision, represented as strings. How much is any size? Is it really necessary? How big is the default float in PHP? Are there any good advice regarding this or things to keep in mind?

    Read the article

  • C#: Accessing a Dictionary.Keys Key through a numeric index

    - by Michael Stum
    I'm using a Dictionary<string, int> where the int is a count of the key. Now, I need to access the last-inserted Key inside the Dictionary, but i do not know the name of it. The obvious attempt: int LastCount = mydict[mydict.keys[mydict.keys.Count]]; does not work, because Dictionary.Keys does not implement a []-indexer. I just wonder if there is any similar class? I thought about using a Stack, but that only stores a string. I could now create my own struct and then use a Stack<MyStruct>, but I wonder if there is another alternative, essentially a Dictionary that implements an []-indexer on the Keys?

    Read the article

  • Read half precision float (float16 IEEE 754r) binary data in matlab

    - by Michael
    you have been a great help last time, i hope you can give me some advise this time, too. I read a binary file into matlab with bit16 (format = bitn) and i get a string of ones and zeros. bin = '1 00011 1111111111' (16 bits: 1. sign, 2-6. exponent, 7-16. mantissa) According to ftp://www.fox-toolkit.org/pub/fasthalffloatconversion.pdf it can be 'converted' like out = (-1)^bin(1) * 2^(bin(2:6)-15) * 1.bin(7:16) [are exponent and mantissa still binary?] Can someone help me out and tell me how to deal with the 'eeeee' and '1.mmmmmmmmmm' as mentioned in the pdf, please. Thanks a lot! Michael

    Read the article

  • How to compare two times in milliseconds precision?

    - by Marcos Issler
    I have a subtitle text file that works with standart srt format 00:00:00,000 Hour, minutes, seconds, milliseconds. I want to create a timer to update the subtitle screen and check the current time to know what subtitle show on screen. Which is the best to use? NSTimeInterval, NSDate? I think the best is to convert all to times to milliseconds number and compare. But NSTimeInterval works with seconds, not milliseconds. Some clue? Marcos

    Read the article

  • convert integer to a string in a given numeric base in python

    - by Mark Borgerding
    Python allows easy creation of an integer from a string of a given base via int(str,base). I want to perform the inverse: creation of a string from an integer. i.e. I want some function int2base(num,base) such that: int( int2base( X , BASE ) , BASE ) == X the function name/argument order is unimportant For any number X and base BASE that int() will accept. This is an easy function to write -- in fact easier than describing it in this question -- however, I feel like I must be missing something. I know about the functions bin,oct,hex; but I cannot use them for a few reasons: Those functions are not available on older versions of python with which I need compatibility (2.2) I want a general solution that can be called the same way for different bases I want to allow bases other than 2,8,16 Related Python elegant inverse function of int(string,base) Interger to base-x system using recursion in python Base 62 conversion in Python How to convert an integer to the shortest url-safe string in Python?

    Read the article

  • Multiplication algorithm for abritrary precision (bignum) integers.

    - by nn
    Hi, I'm writing a small bignum library for a homework project. I am to implement Karatsuba multiplication, but before that I would like to write a naive multiplication routine. I'm following a guide written by Paul Zimmerman titled "Modern Computer Arithmetic" which is freely available online. On page 4, there is a description of an algorithm titled BasecaseMultiply which performs gradeschool multiplication. I understand step 2, 3, where B^j is a digit shift of 1, j times. But I don't understand step 1 and 3, where we have A*b_j. How is this multiplication meant to be carried out if the bignum multiplication hasn't been defined yet? Would the operation "*" in this algorithm just be the repeated addition method? Here is the parts I have written thus far. I have unit tested them so they appear to be correct for the most part: The structure I use for my bignum is as follows: #define BIGNUM_DIGITS 2048 typedef uint32_t u_hw; // halfword typedef uint64_t u_w; // word typedef struct { unsigned int sign; // 0 or 1 unsigned int n_digits; u_hw digits[BIGNUM_DIGITS]; } bn; Currently available routines: bn *bn_add(bn *a, bn *b); // returns a+b as a newly allocated bn void bn_lshift(bn *b, int d); // shifts d digits to the left, retains sign int bn_cmp(bn *a, bn *b); // returns 1 if a>b, 0 if a=b, -1 if a<b

    Read the article

  • Numeric Order By In Transact SQL (Ordering As String Instead Of Int)

    - by Pyronaut
    I have an issue where I am trying to order a result set by what I believe to be a numberic column in my database. However when I get the result set, It has sorted the column as if it was a string (So alphabetically), instead of sorting it as an int. As an example. I have these numbers, 1 , 2, 3, 4, 5, 10, 11 When I order by in Transact SQL, I get back : 1, 10, 11, 2, 3, 4, 5 I had the same issue with Datagridview's a while back, And the issue was because of the sorting being done as if it was a string. I assume the same thing is happening here. My full SQL code is : SELECT TOP (12) DATEPART(YEAR, [OrderDate]) AS 'Year', DATEPART(MONTH, [OrderDate]) AS 'Month' , COUNT(OrderRef) AS 'OrderCount' FROM [Order] WHERE [Status] LIKE('PaymentReceived') OR [Status] LIKE ('Shipped') GROUP BY DATEPART(MONTH, [OrderDate]), DATEPART(YEAR, [OrderDate]) ORDER BY DATEPART(YEAR, OrderDate) DESC, DATEPART(MONTH, OrderDate) desc DO NOTE The wrong sorting only happens when I cam calling the function from Visual Studio. As in my code is : using (SqlConnection conn = GetConnection()) { string query = @"SELECT TOP (12) DATEPART(YEAR, [OrderDate]) AS 'Year', DATEPART(MONTH, [OrderDate]) AS 'Month' , COUNT(OrderRef) AS 'OrderCount' FROM [Order] WHERE [Status] LIKE('PaymentReceived') OR [Status] LIKE ('Shipped') GROUP BY DATEPART(MONTH, [OrderDate]), DATEPART(YEAR, [OrderDate]) ORDER BY DATEPART(YEAR, OrderDate) DESC, DATEPART(MONTH, OrderDate) desc"; SqlCommand command = new SqlCommand(query, conn); command.CommandType = CommandType.Text; using (SqlDataReader reader = command.ExecuteReader()) etc. When I run the statement in MSSQL server, there is no issues. I am currently using MSSQL 2005 express edition, And Visual Studio 2005. I have tried numerous things that are strewn across the web. Including using Convert() and ABS() to no avail. Any help would be much appreciated.

    Read the article

  • Hashes vs Numeric id's

    - by Karan Bhangui
    When creating a web application that some how displays the display of a unique identifier for a recurring entity (videos on YouTube, or book section on a site like mine), would it be better to use a uniform length identifier like a hash or the unique key of the item in the database (1, 2, 3, etc). Besides revealing a little, what I think is immaterial, information about the internals of your app, why would using a hash be better than just using the unique id? In short: Which is better to use as a publicly displayed unique identifier - a hash value, or a unique key from the database? Edit: I'm opening up this question again because Dmitriy brought up the good point of not tying down the naming to db specific property. Will this sort of tie down prevent me from optimizing/normalizing the database in the future? The platform uses php/python with ISAM /w MySQL.

    Read the article

  • matlab precision determint problem

    - by ldigas
    I have the following program format compact; format short g; clear; clc; L = 140; J = 77; Jm = 10540; G = 0.8*10^8; d = L/3; for i=1:500000 omegan=1.+0.0001*i; a(1,1) = ((omegan^2)*(Jm/(G*J))*d^2)-2; a(1,2) = 2; a(1,3) = 0; a(1,4) = 0; a(2,1) = 1; a(2,2) = ((omegan^2)*(Jm/(G*J))*d^2)-2; a(2,3) = 1; a(2,4) = 0; a(3,1) = 0; a(3,2) = 1; a(3,3) = ((omegan^2)*(Jm/(G*J))*d^2)-2; a(3,4) = 1; a(4,1) = 0; a(4,2) = 0; a(4,3) = 2; a(4,4) = ((omegan^2)*(Jm/(G*J))*d^2)-2; if(abs(det(a))<1E-10) sprintf('omegan= %8.3f det= %8.3f',omegan,det(a)) end end Analytical solution of the above system, and the same program written in fortran gives out values of omegan equal to 16.3818 and 32.7636 (fortran values; analytical differ a little, but they're there somewhere). So, now I'm wondering ... where am I going wrong with this ? Why is matlab not giving the expected results ? (this is probably something terribly simple, but it's giving me headaches)

    Read the article

  • LabVIEW: converting numeric array to string array

    - by JaysonFix
    Using LabVIEW 2009, I have a VI that outputs an array of U64 integers. I'd like the user to be able to perform discrete selection from among the elements of this array. I'm thinking of accomplishing this by programmatically populating a Menu Ring (as shown at http://digital.ni.com/public.nsf/allkb/FB0409491FAB16FA86256D08004FCE7E). However, I apparently need to convert my array of U64 ints to an array of strings, as it is an array of strings that is used to populate the Menu Ring. My question: how can I convert the array of U64 ints to an array of strings?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >