Search Results

Search found 2558 results on 103 pages for 'significant digits'.

Page 16/103 | < Previous Page | 12 13 14 15 16 17 18 19 20 21 22 23  | Next Page >

  • Encoding / Error Correction Challenge

    - by emi1faber
    Is it mathematically feasible to encode and initial 4 byte message into 8 bytes and if one of the 8 bytes is completely dropped and another is wrong to reconstruct the initial 4 byte message? There would be no way to retransmit nor would the location of the dropped byte be known. If one uses Reed Solomon error correction with 4 "parity" bytes tacked on to the end of the 4 "data" bytes, such as DDDDPPPP, and you end up with DDDEPPP (where E is an error) and a parity byte has been dropped, I don't believe there's a way to reconstruct the initial message (although correct me if I am wrong)... What about multiplying (or performing another mathematical operation) the initial 4 byte message by a constant, then utilizing properties of an inverse mathematical operation to determine what byte was dropped. Or, impose some constraints on the structure of the message so every other byte needs to be odd and the others need to be even. Alternatively, instead of bytes, it could also be 4 decimal digits encoded in some fashion into 8 decimal digits where errors could be detected & corrected under the same circumstances mentioned above - no retransmission and the location of the dropped byte is not known. I'm looking for any crazy ideas anyone might have... Any ideas out there?

    Read the article

  • sed/awk or other: one-liner to increment a number by 1 keeping spacing characters

    - by WizardOfOdds
    EDIT: I don't know in advance at which "column" my digits are going to be and I'd like to have a one-liner. Apparently sed doesn't do arithmetic, so maybe a one-liner solution based on awk? I've got a string: (notice the spacing) eh oh 37 and I want it to become: eh oh 36 (so I want to keep the spacing) Using awk I don't find how to do it, so far I have: echo "eh oh 37" | awk '$3>=0&&$3<=99 {$3--} {print}' But this gives: eh oh 36 (the spacing characters where lost, because the field separator is ' ') Is there a way to ask awk something like "print the output using the exact same field separators as the input had"? Then I tried yet something else, using awk's sub(..,..) method: ' sub(/[0-9][0-9]/, ...) {print}' but no cigar yet: I don't know how to reference the regexp and do arithmetic on it in the second argument (which I left with '...' for now). Then I tried with sed, but got stuck after this: echo "eh oh 37" | sed -e 's/\([0-9][0-9]\)/.../' Can I do arithmetic from sed using a reference to the matching digits and have the output not modify the number of spacing characters? Note that it's related to my question concerning Emacs and how to apply this to some (big) Emacs region (using a replace region with Emacs's shell-command-on-region) but it's not an identical question: this one is specifically about how to "keep spaces" when working with awk/sed/etc.

    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

  • Endianness inside CPU registers

    - by Abhishek Tamhane
    I need help understanding endianness inside CPU registers of x86 processors. I wrote this small assembly program: section .data section .bss section .text global _start _start: nop mov eax, 0x78FF5ABC mov ebx,'WXYZ' nop ; GDB breakpoint here. mov eax, 1 mov ebx, 0 int 0x80 I ran this program in GDB with a breakpoint on line number 10 (commented in the source above). At this breakpoint, info registers shows the value of eax=0x78ff5abc and ebx=0x5a595857. Since the ASCII codes for W, X, Y, Z are 57, 58, 59, 5A respectively; and intel is little endian, 0x5a595857 seems like the correct byte order (least significant byte first). Why isn't then the output for eax register 0xbc5aff78 (least significant byte of the number 0x78ff5abc first) instead of 0x78ff5abc?

    Read the article

  • Need help with an AJAX workflow

    - by Anders
    Sorry I couldn't be more descriptive with the title, I will elaborate fully below: I have a web application that I want to implement some AJAX functionality into. Currently, it is running ASP.NET 3.5 with VB.NET codebehind. My current "problem" is I want to dynamically be able to populate a DIV when a user clicks an item on a list. The list item currently contains a HttpUtility.UrlEncode() (ASP.NET) string of the content that should appear in the DIV. Example: <li onclick="setFAQ('The+maximum+number+of+digits+a+patient+account+number+can+contain+is+ten+(10).');"> What is the maximum number of digits a patient account number can contain?</li> I can decode the string partially with the JavaScript function unescape() but it does not fully decode the string. I would much rather pass the JavaScript function the faq ID then somehow pull the information from the database where it originates. I am 99% sure it is impossible to call an ASP function from within a JavaScript function, so I am kind of stumped. I am kind of new to AJAX/ASP.NET so this is a learning experience for me.

    Read the article

  • C++ long long manipulation

    - by Krakkos
    Given 2 32bit ints iMSB and iLSB int iMSB = 12345678; // Most Significant Bits of file size in Bytes int iLSB = 87654321; // Least Significant Bits of file size in Bytes the long long form would be... // Always positive so use 31 bts long long full_size = ((long long)iMSB << 31); full_size += (long long)(iLSB); Now.. I don't need that much precision (that exact number of bytes), so, how can I convert the file size to MiBytes to 3 decimal places and convert to a string... tried this... long double file_size_megs = file_size_bytes / (1024 * 1024); char strNumber[20]; sprintf(strNumber, "%ld", file_size_megs); ... but dosen't seem to work. i.e. 1234567899878Bytes = 1177375.698MiB ??

    Read the article

  • silverlight for .NET / CLR based numerical computing on osx

    - by Jonathan Shore
    I'm interested in using F# for numerical work, but my platforms are not windows based. Mono still has a significant performance penalty for programs that generate a significant amount of short-lived objects (as would be typical for functional languages). Silverlight is available on OSX. I had seen some reference indicating that assemblies compiled in the usual way could not be referenced, but not clear on the details. I'm not interested in UIs, but wondering whether could use the VM bundled with silverlight effectively for execution? I would want to be able to reference a large library of numerical models I already have in java (cross-compiled via IKVM to .NET assemblies) and a new codebase written in F#. My hope would be that the silverlight VM on OSX has good performance and can reference external assemblies and native libraries. Is this doable?

    Read the article

  • compact Number formatting behavior in Java (automatically switch between decimal and scientific notation)

    - by kostmo
    I am looking for a way to format a floating point number dynamically in either standard decimal format or scientific notation, depending on the value of the number. For moderate magnitudes, the number should be formatted as a decimal with trailing zeros suppressed. If the floating point number is equal to an integral value, the decimal point should also be suppressed. For extreme magnitudes (very small or very large), the number should be expressed in scientific notation. Alternately stated, if the number of characters in the expression as standard decimal notation exceeds a certain threshold, switch to scientific notation. I should have control over the maximum number of digits of precision, but I don't want trailing zeros appended to express the minimum precision; all trailing zeros should be suppressed. Basically, it should optimize for compactness and readability. 2.80000 - 2.8 765.000000 - 765 0.0073943162953 - 0.00739432 (limit digits of precision—to 6 in this case) 0.0000073943162953 - 7.39432E-6 (switch to scientific notation if the magnitude is small enough—less than 1E-5 in this case) 7394316295300000 - 7.39432E+6 (switch to scientific notation if the magnitude is large enough—for example, when greater than 1E+10) 0.0000073900000000 - 7.39E-6 (strip trailing zeros from significand in scientific notation) 0.000007299998344 - 7.3E-6 (rounding from the 6-digit precision limit causes this number to have trailing zeros which are stripped) Here's what I've found so far: The .toString() method of the Number class does most of what I want, except it doesn't upconvert to integer representation when possible, and it will not express large integral magnitudes in scientific notation. Also, I'm not sure how to adjust the precision. The "%G" format string to the String.format(...) function allows me to express numbers in scientific notation with adjustable precision, but does not strip trailing zeros. I'm wondering if there's already some library function out there that meets these criteria. I guess the only stumbling block for writing this myself is having to strip the trailing zeros from the significand in scientific notation produced by %G.

    Read the article

  • Is there a way to do 'correct' arithmetical rounding in .NET? / C#

    - by Markus
    I'm trying to round a number to it's first decimal place and, considering the different MidpointRounding options, that seems to work well. A problem arises though when that number has sunsequent decimal places that would arithmetically affect the rounding. An example: With 0.1, 0.11..0.19 and 0.141..0.44 it works: Math.Round(0.1, 1) == 0.1 Math.Round(0.11, 1) == 0.1 Math.Round(0.14, 1) == 0.1 Math.Round(0.15, 1) == 0.2 Math.Round(0.141, 1) == 0.1 But with 0.141..0.149 it always returns 0.1, although 0.146..0.149 should round to 0.2: Math.Round(0.145, 1, MidpointRounding.AwayFromZero) == 0.1 Math.Round(0.146, 1, MidpointRounding.AwayFromZero) == 0.1 Math.Round(0.146, 1, MidpointRounding.ToEven) == 0.1 Math.Round(0.146M, 1, MidpointRounding.ToEven) == 0.1M Math.Round(0.146M, 1, MidpointRounding.AwayFromZero) == 0.1M I tried to come up with a function that addresses this problem, and it works well for this case, but of course it glamorously fails if you try to round i.e. 0.144449 to it's first decimal digit (which should be 0.2, but results 0.1.) (That doesn't work with Math.Round() either.) private double round(double value, int digit) { // basically the old "add 0.5, then truncate to integer" trick double fix = 0.5D/( Math.Pow(10D, digit+1) )*( value = 0 ? 1D : -1D ); double fixedValue = value + fix; // 'truncate to integer' - shift left, round, shift right return Math.Round(fixedValue * Math.Pow(10D, digit)) / Math.Pow(10D, digit); } I assume a solution would be to enumerate all digits, find the first value larger than 4 and then round up, or else round down. Problem 1: That seems idiotic, Problem 2: I have no idea how to enumerate the digits without a gazillion of multiplications and subtractios. Long story short: What is the best way to do that?

    Read the article

  • Radix Sort in Python [on hold]

    - by Steven Ramsey
    I could use some help. How would you write a program in python that implements a radix sort? Here is some info: A radix sort for base 10 integers is a based on sorting punch cards, but it turns out the sort is very ecient. The sort utilizes a main bin and 10 digit bins. Each bin acts like a queue and maintains its values in the order they arrive. The algorithm begins by placing each number in the main bin. Then it considers the ones digit for each value. The rst value is removed and placed in the digit bin corresponding to the ones digit. For example, 534 is placed in digit bin 4 and 662 is placed in the digit bin 2. Once all the values in the main bin are placed in the corresponding digit bin for ones, the values are collected from bin 0 to bin 9 (in that order) and placed back in the main bin. The process continues with the tens digit, the hundreds, and so on. After the last digit is processed, the main bin contains the values in order. Use randint, found in random, to create random integers from 1 to 100000. Use a list comphrension to create a list of varying sizes (10, 100, 1000, 10000, etc.). To use indexing to access the digits rst convert the integer to a string. For this sort to work, all numbers must have the same number of digits. To zero pad integers with leading zeros, use the string method str.zfill(). Once main bin is sorted, convert the strings back to integers. I'm not sure how to start this, Any help is appreciated. Thank you.

    Read the article

  • JQuery Validate: only takes the first addMethod?

    - by Neuquino
    Hi, I need to add multiple custom validations to one form. I have 2 definitions of addMethod. But it only takes the first one... here is the code. $(document).ready(function() { $.validator.addMethod("badSelectionB",function(){ var comboValues = []; for(var i=0;i<6;i++){ var id="comision_B_"+(i+1); var comboValue=document.getElementById(id).value; if($.inArray(comboValue,comboValues) != 0){ comboValues.push(comboValue); }else{ return false; } } return true; },"Seleccione una única prioridad por comisión."); $.validator.addMethod("badSelectionA",function(){ var comboValues = []; for(var i=0;i<6;i++){ var id="comision_A_"+(i+1); var comboValue=document.getElementById(id).value; if($.inArray(comboValue,comboValues) != 0){ comboValues.push(comboValue); }else{ return false; } } return true; },"Seleccione una única prioridad por comisión."); $("#inscripcionForm").validate( { rules : { nombre : "required", apellido : "required", dni : { required: true, digits: true, }, mail : { required : true, email : true, }, comision_A_6: { badSelectionA:true, }, comision_B_6: { badSelectionB: true, } }, messages : { nombre : "Ingrese su nombre.", apellido : "Ingrese su apellido.", dni : { required: "Ingrese su dni.", digits: "Ingrese solo números.", }, mail : { required : "Ingrese su correo electrónico.", email: "El correo electrónico ingresado no es válido." } }, }); }); Do you have any clue of what is happening? Thanks in advance,

    Read the article

  • Calculate the digital root of a number

    - by Gregory Higley
    A digital root, according to Wikipedia, is "the number obtained by adding all the digits, then adding the digits of that number, and then continuing until a single-digit number is reached." For instance, the digital root of 99 is 9, because 9 + 9 = 18 and 1 + 8 = 9. My Haskell solution -- and I'm no expert -- is as follows. digitalRoot n | n < 10 = n | otherwise = digitalRoot . sum . map (\c -> read [c]) . show $ n As a language junky, I'm interested in seeing solutions in as many languages as possible, both to learn about those languages and possibly to learn new ways of using languages I already know. (And I know at least a bit of quite a few.) I'm particularly interested in the tightest, most elegant solutions in Haskell and REBOL, my two principal "hobby" languages, but any ol' language will do. (I pay the bills with unrelated projects in Objective C and C#.) Here's my (verbose) REBOL solution: digital-root: func [n [integer!] /local added expanded] [ either n < 10 [ n ][ expanded: copy [] foreach c to-string n [ append expanded to-integer to-string c ] added: 0 foreach e expanded [ added: added + e ] digital-root added ] ] EDIT: As some have pointed out either directly or indirectly, there's a quick one-line expression that can calculate this. You can find it in several of the answers below and in the linked Wikipedia page. (I've awarded Varun the answer, as the first to point it out.) Wish I'd known about that before, but we can still bend our brains with this question by avoiding solutions that involve that expression, if you're so inclined. If not, Crackoverflow has no shortage of questions to answer. :)

    Read the article

  • Binary files printing and desired precision

    - by yCalleecharan
    Hi, I'm printing a variable say z1 which is a 1-D array containing floating point numbers to a text file so that I can import into Matlab or GNUPlot for plotting. I've heard that binary files (.dat) are smaller than .txt files. The definition that I currently use for printing to a .txt file is: void create_out_file(const char *file_name, const long double *z1, size_t z_size){ FILE *out; size_t i; if((out = _fsopen(file_name, "w+", _SH_DENYWR)) == NULL){ fprintf(stderr, "***> Open error on output file %s", file_name); exit(-1); } for(i = 0; i < z_size; i++) fprintf(out, "%.16Le\n", z1[i]); fclose(out); } I have three questions: Are binary files really more compact than text files?; If yes, I would like to know how to modify the above code so that I can print the values of the array z1 to a binary file. I've read that fprintf has to be replaced with fwrite. My output file say dodo.dat should contain the values of array z1 with one floating number per line. I have %.16Le up in my code but I think that %.15Le is right as I have 15 precision digits with long double. I have put a dot (.) in the width position as I believe that this allows expansion to an arbitrary field to hold the desired number. Am I right? As an example with %.16Le, I can have an output like 1.0047914240730432e-002 which gives me 16 precision digits and the width of the field has the right width to display the number correctly. Is placing a dot (.) in the width position instead of a width value a good practice? Thanks a lot...

    Read the article

  • Storing script files outside web root

    - by memilanuk
    I've seen recommendations to store some or all php include files some place other than in the web document root directory (username/public_html in my case) for the specific reason of protecting php files with sensitive information (like database connection and login info) in the event that the web server hiccups and stops protecting php files and they become 'visible' to outsiders who know where to look. It seems somewhat paranoid to me, but I'm guessing people have gotten burned badly on this before so I'm willing to go along. The suggestion usually takes the form of having the include files in something like '../include_files/' so its not directly in the document root and not directly accessible to outsiders through the web server. My question is this: is there a significant difference in security between that way and just putting your 'include_files' directory under the document root and sticking an .htaccess file in there (with the appropriate entries)? Would putting an .htaccess file in '../include_files/' make any significant improvement there? TIA, Monte

    Read the article

  • substitution cypher with different alphabet length

    - by seanizer
    I would like to implement a simple substitution cypher to mask private ids in URLs I know how my IDs will look like (combination of upperchase ascii, digits and underscore), and they will be rather long, as they are composed keys. I would like to use a longer alphabet to shorten the resulting codes (I'd like to use upper and lower case ascii letters, digits and nothing else). So my incoming alphabet would be [A-Z0-9_] (37 chars) and my outgoing alphabet would be [A-Za-z0-9] (62 chars) so a compression of almost 50% would be available. let's say my URLs look like this: /my/page/GFZHFFFZFZTFZTF_24_F34 and I want them to look like this instead: /my/page/Ft32zfegZFV5 Obviously both arrays would be shuffled to bring some random order in. This does not have to be secure. if someone figures it out: fine, but I don't want the scheme to be obvious. My desired solution would be to convert the string to an integer representation of radix 37, convert the radix to 62 and use the second alphabet to write out that number. is there any sample code available that does something similar? Integer.parseInt ( http://java.sun.com/javase/6/docs/api/java/lang/Integer.html#parseInt%28java.lang.String,%20int%29 ) has some similar logic, but it is hard-coded to use standard digit behavior Any hints? I am using java to implement this but code or pseudo-code in any other language is of course also helpful

    Read the article

  • How would I find all sets of N single-digit, non-repeating numbers that add up to a given sum in PHP

    - by TerranRich
    Let's say I want to find all sets of 5 single-digit, non-repeating numbers that add up to 30... I'd end up with [9,8,7,5,1], [9,8,7,4,2], [9,8,6,4,3], [9,8,6,5,2], [9,7,6,5,3], and [8,7,6,5,4]. Each of those sets contains 5 non-repeating digits that add up to 30, the given sum. Any help would be greatly appreciated. Even just a starting point for me to use would be awesome. I came up with one method, which seems like a long way of going about it: get all unique 5-digit numbers (12345, 12346, 12347, etc.), add up the digits, and see if it equals the given sum (e.g. 30). If it does, add it to the list of possible matching sets. I'm doing this for a personal project, which will help me in solving Kakuro puzzles without actually solving the whole thing at once. Yeah, it may be cheating, but it's... it's not THAT bad... :P

    Read the article

  • need help with Java solution /newbie

    - by Racket
    Hi, I'm new to programming in general so i'm trying to be as specific as possible in this question. There's this book that i'm doing some exercises on. I managed to do more than half of what they say, but it's just one input that I have been struggling to find out. I'll write the question and thereafter my code, "Write an application that creates and prints a random phone number of the form XXX-XXX-XXXX. Include the dashes in the output. Do not let the first three digits contain an 8 or 9 (but don't be more restrictive than that), and make sure that the second set of three digits is not greater than 742. Hint: Think through the easiest way to construct the phone number. Each diigit does not have to be determined separately." OK, the highlighted sentence is what i'm looking at. Here's my code: import java.util.Random; public class PP33 { public static void main (String[] args) { Random rand = new Random(); int num1, num2, num3; num1 = rand.nextInt(900) + 100; num2 = rand.nextInt(643) + 100; num3 = rand.nextInt(9000) + 1000; System.out.println(num1+"-"+num2+"-"+num3); } } How am I suppose to do this? I'm on chapter 3 so we have not yet discussed if statements etcetera, but Aliases, String class, Packages, Import declaration, Random Class, Math Class, Formatting output (decimal- & numberFormat), Printf, Enumeration & Wrapper classes + autoboxing. So consider answer the question based only on these assumptions, please. The code doesn't have any errors. Thank you!

    Read the article

  • jquery calculation sum two different type of item

    - by st4n
    I'm writing a script like the example shown in the demo where All of the "Total" values (Including the "Grand Total") are Automatically Calculated using the calc () method. at this link: But I have some fields in which to apply the equation qty * price, and others where I want to do other operations .. you can tell me how? thank you very much i try with this, but it is a very stupid code .. and the grandTotal .. not sum the two different fields: function recalc() { $("[id^=total_item]").calc("qty * price", { qty: $("input[name^=qty_item_]"), price: $("[id^=price_item_]") }, function (s){ // return the number as a dollar amount return "$" + s.toFixed(2); }, function ($this){ // sum the total of the $("[id^=total_item]") selector var sum = $this.sum(); $("#grandTotal").text( // round the results to 2 digits "$" + sum.toFixed(2) ); }); $("[id^=total_otheritem]").calc("qty1 / price1", { qty1: $("input[name^=qty_other_]"), price1: $("[id^=price_other_]") }, function (s){ // return the number as a dollar amount return "$" + s.toFixed(2); }, function ($this){ var sum = $this.sum(); $("#grandTotal").text( // round the results to 2 digits "$" + sum.toFixed(2) ); }); }

    Read the article

  • How do I make this nested for loop, testing sums of cubes, more efficient?

    - by Brian J. Fink
    I'm trying to iterate through all the combinations of pairs of positive long integers in Java and testing the sum of their cubes to discover if it's a Fibonacci number. I'm currently doing this by using the value of the outer loop variable as the inner loop's upper limit, with the effect being that the outer loop runs a little slower each time. Initially it appeared to run very quickly--I was up to 10 digits within minutes. But now after 2 full days of continuous execution, I'm only somewhere in the middle range of 15 digits. At this rate it may end up taking a whole year just to finish running this program. The code for the program is below: import java.lang.*; import java.math.*; public class FindFib { public static void main(String args[]) { long uLimit=9223372036854775807L; //long maximum value BigDecimal PHI=new BigDecimal(1D+Math.sqrt(5D)/2D); //Golden Ratio for(long a=1;a<=uLimit;a++) //Outer Loop, 1 to maximum for(long b=1;b<=a;b++) //Inner Loop, 1 to current outer { //Cube the numbers and add BigDecimal c=BigDecimal.valueOf(a).pow(3).add(BigDecimal.valueOf(b).pow(3)); System.out.print(c+" "); //Output result //Upper and lower limits of interval for Mobius test: [c*PHI-1/c,c*PHI+1/c] BigDecimal d=c.multiply(PHI).subtract(BigDecimal.ONE.divide(c,BigDecimal.ROUND_HALF_UP)), e=c.multiply(PHI).add(BigDecimal.ONE.divide(c,BigDecimal.ROUND_HALF_UP)); //Mobius test: if integer in interval (floor values unequal) Fibonacci number! if (d.toBigInteger().compareTo(e.toBigInteger())!=0) System.out.println(); //Line feed else System.out.print("\r"); //Carriage return instead } //Display final message System.out.println("\rDone. "); } } Now the use of BigDecimal and BigInteger was delibrate; I need them to get the necessary precision. Is there anything other than my variable types that I could change to gain better efficiency?

    Read the article

  • Standard (cross-platform) way for bit manipulation

    - by Kiril Kirov
    As are are different binary representation of the numbers (for example, take big/little endian), is this cross-platform: some_unsigned_type variable = some_number; // set n-th bit, starting from 1, // right-to-left (least significant-to most significant) variable |= ( 1 << ( n - 1 ) ); // clear the same bit: variable &= ~( 1 << ( n - 1 ) ); In other words, does the compiler always take care of the different binary representation of the unsigned numbers, or it's platform-specific? And what if variable is signed integral type (for example, int) and its value is zero positive negative? What does the Standard say about this? P.S. And, yes, I'm interesting in both - C and C++, please don't tell me they are different languages, because I know this :) I can paste real example, if needed, but the post will become too long

    Read the article

  • What Use are Threads Outside of Parallel Problems on MultiCore Systesm?

    - by Robert S. Barnes
    Threads make the design, implementation and debugging of a program significantly more difficult. Yet many people seem to think that every task in a program that can be threaded should be threaded, even on a single core system. I can understand threading something like an MPEG2 decoder that's going to run on a multicore cpu ( which I've done ), but what can justify the significant development costs threading entails when you're talking about a single core system or even a multicore system if your task doesn't gain significant performance from a parallel implementation? Or more succinctly, what kinds of non-performance related problems justify threading? Edit Well I just ran across one instance that's not CPU limited but threads make a big difference: TCP, HTTP and the Multi-Threading Sweet Spot Multiple threads are pretty useful when trying to max out your bandwidth to another peer over a high latency network connection. Non-blocking I/O would use significantly less local CPU resources, but would be much more difficult to design and implement.

    Read the article

  • jQuery Validate on form submitted by JavaScript

    - by Daniel
    My form is submitted by a link using JavaScript, but I am also trying to validate the from justing jQuery validate. The validation doesn't work when submitted by the link, but it does if I change the link to a submit button. What am I doing wrong? My form: <form id="findmatch" method="post" action="search"> <div> <label class="formlabel">Match Type <input type="text" name="matchtype" id="matchtype" class="forminput" /> </label> <label class="formlabel">Location (postcode) <input type="text" name="location" id="location" class="forminput" /> </label> <label class="formlabel">Radius (miles) <input type="text" name="Radius" id="Radius" class="forminput" /> </label> <label class="formlabel">Keywords <input type="text" onblur="javascript:usePointFromPostcode(document.getElementById('location').value, showCompleteLatLng)" onchange="javascript:usePointFromPostcode(document.getElementById('location').value, showCompleteLatLng)" name="keywords" id="keywords" class="forminput" /> </label> <input id="lat" class="hidden" name="lat" type="text" value="" /> <input id="lon" class="hidden" name="lon" type="text" value="" /> <a href="javascript:document.getElementById('findmatch').submit();" onmouseover="javascript:usePointFromPostcode(document.getElementById('location').value, showCompleteLatLng)" class="submit">Search</a> </div> </form> And my jQuery is <script type="text/javascript"> $(document).ready(function () { $("#findmatch").validate({ rules: { location: "required", Radius: { required: true, digits: true }, keywords: "required" }, messages: { location: "Please enter your postcode", Radius: { required: "Please enter a radius", digits: "Please only enter numbers" }, keywords: "Please enter the keywords you wish to search for" } }); }); </script>

    Read the article

  • Why is my Android app force closing when I try to check if an EditText has a double

    - by user336861
    Scanner scanner = new Scanner(lapsPerMile_st); if (!scanner.hasNextDouble()) { Context context = getApplicationContext(); String msg = "Please Enter Digits and Decmials Only"; int duration = Toast.LENGTH_LONG; Toast.makeText(context, msg, duration).show(); lapsPerMileEditText.setText(""); return; } else { //Edit box has only digits, Set data and display stats data.setLapsPerMile(Integer.parseInt(lapsPerMile_st)); lapsRunLabel.setVisibility(0); lapsRunTextView.setText(Integer.toString(data.getLapsRun())); milesRunLabel.setVisibility(0); milesRunTextView.setText(Double.toString(data.getLapsRun()/data.getLapsPerMile())); } <EditText android:id="@+id/mileCount" android:layout_width="100dp" android:layout_height="wrap_content" android:layout_marginTop="110dp" android:inputType="numberDecimal" android:maxLength="4" /> For some reason if I enter a non decimal number such as 3, or 5, it works fine but when I enter a floating point such as 3.4 or 5.8 it force closes. I cant seem to figure out whats going on. Any ideas? Thanks

    Read the article

< Previous Page | 12 13 14 15 16 17 18 19 20 21 22 23  | Next Page >