Search Results

Search found 1348 results on 54 pages for 'floating accuracy'.

Page 13/54 | < Previous Page | 9 10 11 12 13 14 15 16 17 18 19 20  | Next Page >

  • Inaccurate Logarithm in Python

    - by Avihu Turzion
    I work daily with Python 2.4 at my company. I used the versatile logarithm function 'log' from the standard math library, and when I entered log(2**31, 2) it returned 31.000000000000004, which struck me as a bit odd. I did the same thing with other powers of 2, and it worked perfectly. I ran 'log10(2**31) / log10(2)' and I got a round 31.0 I tried running the same original function in Python 3.0.1, assuming that it was fixed in a more advanced version. Why does this happen? Is it possible that there are some inaccuracies in mathematical functions in Python?

    Read the article

  • x86-64 long double precision

    - by aaa
    hello. What is the actual precision of long double on Intel 64-bit platforms? is it 80 bits padded to 128 or actual 128 bit? if former, besides going gmp, is there another option to achieve true 128 precision?

    Read the article

  • Contact form contents spilling out of container div on window resize.

    - by Alex C
    I'm trying to get my contact form to not spill its contents out of the parent div when I resize the viewport. How can I go about doing this? I have used float clearing to prevent this as I understood it was supposed to be used, but it isn't working. What should I do to fix this? here is the page in question. also I have a similar problem with the header.. the menu drops below the header text if I make the browser window smaller. Thanks for any help you all have to offer. http://countercharge.net/catsite/index.php?P=contact

    Read the article

  • Reducing decimal places in Delphi

    - by Hendriksen123
    I am storing a list of numbers (as Double) in a text file, then reading them out again. When I read them out of the text file however, the numbers are placed into the text box as 1.59993499 for example, instead of 1.6. AssignFile(Pipe, 'EconomicData.data'); Reset(Pipe); For i := 1 to 15 Do ReadLn(Pipe, SavedValue[i]); CloseFile(Pipe); Edit1.Text := FloatToStr(SavedValue[1]); The text in Edit1.text, from the code above, would be 1.59999... instead of the 1.6 in the text file. How can i make it so the text box displays the original value (1.6)?

    Read the article

  • Faster float to int conversion in Python

    - by culebrón
    Here's a piece of code that takes most time in my program, according to timeit statistics. It's a dirty function to convert floats in [-1.0, 1.0] interval into unsigned integer [0, 2**32]. How can I accelerate floatToInt? piece = [] rng = range(32) for i in rng: piece.append(1.0/2**i) def floatToInt(x): n = x + 1.0 res = 0 for i in rng: if n >= piece[i]: res += 2**(31-i) n -= piece[i] return res

    Read the article

  • negative precision values in ostream

    - by daz-fuller
    This is more of a question of curiosity but does anyone know how negative precision values are handled in C++? For example: double pi = 3.14159265; cout.precision(-10); cout.setf(ios::fixed, ios::floatfield); cout << pi << endl; I've tried this out and using GCC and it seems that the precision value is ignored but I was curious if there is some official line on what happens in this situation.

    Read the article

  • jQuery: Combining "filterable portfolio" and Masonry layout

    - by katharina
    Hi, I'm trying to combine the "filterable portfolio" (http://net.tutsplus.com/tutorials/javascript-ajax/creating-a-filterable-portfolio-with-jquery/) with the Masonry layout ... so I want my items to readjust with masonery after I filtered them, but they stay in the position where masonery put them... here's my very rough first website draft: http://waynetest.kilu.de/lula/ (work obviously in progress..;)) Is there a possibility to combine both js-scripts? thanks a lot, katharina

    Read the article

  • Dynamic margin (or simulation of margin) between left floated divs

    - by BugBusterX
    I have a number of divs floated left. When browser is resized they move down or up based on how many can fit on the line. I was wondering if there is a way to dynamically (with css) have those divs align (or have margin) in a way, that they would always fill the entire screen space by having their marhin resize? In other words margin between them would resize while browser is resized, but as soon as another div can fit it will be added in the line, or if minimum margin is reached and passed another div goes to next line while margins expand again. Here's an example how it is now, resize the wondow to see he leftover space that I want to "fill" <html> <head> <style> .test { float:left; width: 100px; height:100px; background-color: grey; margin: 0 10px 10px 0; } </style> </head> <body> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> <div class="test"></div> </body> </html>

    Read the article

  • Can bad stuff happen when dividing 1/a very small float?

    - by Jeremybub
    If I want to check that positive float A is less than the inverse square of another positive float B (in C99), could something go wrong if B is very small? I could imagine checking it like if(A<1/(B*B)) but if B is small enough, would this possibly result in infinity? If that were to happen, would the code still work correctly in all situations? in a similar vein, I might do if(1/A>B*B) Which might be slightly better because B*B might be zero if B is small (is this true?) Finally, a solution that I can't imagine being wrong is if(sqrt(1/A)>B) Which I don't think would ever result in zero division, but still might be problematic if A is close to zero. So basically, my questions are Can 1/X ever be infinity if X is greater than zero (but small)? Can X*X ever be zero if X is greater than zero? Will comparisons with infinity work the way I would expect them to?

    Read the article

  • C/C++ - Convert 24-bit signed integer to float

    - by e-t172
    I'm programming in C++. I need to convert a 24-bit signed integer (stored in a 3-byte array) to float (normalizing to [-1.0,1.0]). The platform is MSVC++ on x86 (which means the input is little-endian). I tried this: float convert(const unsigned char* src) { int i = src[2]; i = (i << 8) | src[1]; i = (i << 8) | src[0]; const float Q = 2.0 / ((1 << 24) - 1.0); return (i + 0.5) * Q; } I'm not entirely sure, but it seems the results I'm getting from this code are incorrect. So, is my code wrong and if so, why?

    Read the article

  • How do calculators work with precision?

    - by zoul
    Hello! I wonder how calculators work with precision. For example the value of sin(M_PI) is not exactly zero when computed in double precision: #include <math.h> #include <stdio.h> int main() { double x = sin(M_PI); printf("%.20f\n", x); // 0.00000000000000012246 return 0; } Now I would certainly want to print zero when user enters sin(p). I can easily round somewhere on 1e–15 to make this particular case work, but that’s a hack, not a solution. When I start to round like this and the user enters something like 1e–20, they get a zero back (because of the rounding). The same thing happens when the user enters 1/10 and hits the = key repeatedly — when he reaches the rounding treshold, he gets zero. And yet some calculators return plain zero for sin(p) and at the same time they can work with expressions such as (1e–20)/10 comfortably. Where’s the trick?

    Read the article

  • How to mark empty in a single element in a float array

    - by Vineeth Mohan
    I have a large float (primitive) array and not every element in the array is filled. How can i mark a particular element as EMPTY. I understand this can be achieved by some special symbols but still i would like to know the standard way. Even if i am using some special symbol , how will i handle a situation where the actual data item is the value of special symbol. In short my question is how to implement the NULL feature in a primitive type array in java. PS - The reason why i am not using Float object is to achieve a high memory and speed performance. Thanks Vineeth

    Read the article

  • Why might different computers calculate different arithmetic results in VB.NET?

    - by Eyal
    I have some software written in VB.NET that performs a lot of calculations, mostly extracting jpegs to bitmaps and computing calculations on the pixels like convolutions and matrix multiplication. Different computers are giving me different results despite having identical inputs. What might be the reason? Edit: I can't provide the algorithm because it's proprietary but I can provide all the relevant operations: ULong \ ULong (Turuncating division) Bitmap.Load("filename.bmp') (Load a bitmap into memory) Bitmap.GetPixel(Integer, Integer) (Get a pixel's brightness) Double + Double Double * Double Math.Sqrt(Double) Math.PI Math.Cos(Double) ULong - ULong ULong * ULong ULong << ULong List.OrderBy(Of Double)(Func) Hmm... Is it possible that OrderBy is using a non-stable QuickSort and that QuickSort is using a random pivot? Edit: Just tested, nope. The sort is stable.

    Read the article

  • Adding a div layer on top of a jquery carousel. Tough one.

    - by wilwaldon
    Hey everyone, I have a tough one, well it's tough for me because I'm kinda new to the whole jQuery carousel thing, never built one before this project. Here's my problem. If you go to the TEST SITE you will see a scroller with a blue background about half way down the page. If you mouse onto the "data analytics" slide you should see a black box fade in. Here is my dilemma. I want that black box to be a menu that's connected to the data analytics slide. I've done a mock up for you so you can see what I'm talking about. Here is my scroller code. I'm using jCarousel. <div class="carousel"> <ul> <li> <div id="homeslide1"> testers sdfasdfasdfas asdftjhs iasndkad kasdnf <a href="#" id="#homeslide1-toggle">Close this</a> </div> <a href="#" id="homeslide1-show"><img src="<?php bloginfo('template_url'); ?>/images/home_data_analytics.jpg" width="200" height="94" /></a> </li> <li><img src="<?php bloginfo('template_url'); ?>/images/home_oem_partnerships.jpg" width="200" height="94" /></li> <li><img src="<?php bloginfo('template_url'); ?>/images/home_reporting.jpg" width="200" height="92" /></li> <li><img src="<?php bloginfo('template_url'); ?>/images/home_returning_lost_customers.jpg" width="200" height="92" /></li> <li><img src="<?php bloginfo('template_url'); ?>/images/home_sales.jpg" width="200" height="92" /></li> <li><img src="<?php bloginfo('template_url'); ?>/images/home_service_retention.jpg" width="200" height="92" /></li> </ul> Here is my scroller css /*HOMEPAGE SCROLLER*/ .carousel {!important padding:10px; width: 890px; margin: 0px 0px 0px 26px;} .carousel ul li element.style{height: 94px;} .carousel ul{width: 200px; padding: 5px;} .carouselitem{height: 94px;} .prev{background: url(images/home_left_scroll.png); height: 94px; width: 16px; text-indent: -999px; outline: none; cursor:pointer; float: left;} .next{background: url(images/home_right_scroll.png); height: 94px; width: 16px; text-indent: -999px; outline: none; cursor:pointer; float: right;} .carousel ul li{ padding: 0px 3px 0px 3px; margin: 0px; height:!important 94px; } .home_right_arrow{ width: 16px; float: right;} .home_left_arrow{ width: 16px; float: left;} .homeslide1{ width: 200px; height: 94px;} I've tried all sorts of z-index tricks but can't seem to figure it out on my own. If you solve this riddle I'll buy you a beer if we ever meet up. I'll also give you a high five through the internet. Is there a simple way to do this via jQuery? If so could you point me in the right direction? Thanks so much.

    Read the article

  • How can you transform a set of numbers into mostly whole ones?

    - by Alice
    Small amount of background: I am working on a converter that bridges between a map maker (Tiled) that outputs in XML, and an engine (Angel2D) that inputs lua tables. Most of this is straight forward However, Tiled outputs in pixel offsets (integers of absolute values), while Angel2D inputs OpenGL units (floats of relative values); a conversion factor between these two is needed (for example, 32px = 1gu). Since OpenGL units are abstract, and the camera can zoom in or out if the objects are too small or big, the actual conversion factor isn't important; I could use a random number, and the user would merely have to zoom in or out. But it would be best if the conversion factor was selected such that most numbers outputted were small and whole (or fractions of small whole numbers), because that makes it easier to work with (and the whole point of the OpenGL units is that they are easy to work with). How would I find such a conversion factor reliably? My first attempt was to use the smallest number given; this resulted in no fractions below 1, but often lead to lots of decimal places where the factors didn't line up. Then I tried the mode of the sequence, which lead to the largest number of 1's possible, but often lead to very long floats for background images. My current approach gets the GCD of the whole sequence, which, when it works, works great, but can easily be thrown off course by a single bad apple. Note that while I could easily just pass the numbers I am given along, or pick some fixed factor, or use one of the conversions I specified above, I am looking for a method to reliably scale this list of integers to small, whole numbers or simple fractions, because this would most likely be unsurprising to the end user; this is not a one off conversion. The end users tend to use 1.0 as their "base" for manipulations (because it's simple and obvious), so it would make more sense for the sizes of entities to cluster around this.

    Read the article

  • Problem using the find function in MATLAB

    - by Peter Etchells
    I have two arrays of data that I'm trying to amalgamate. One contains actual latencies from an experiment in the first column (e.g. 0.345, 0.455... never more than 3 decimal places), along with other data from that experiment. The other contains what is effectively a 'look up' list of latencies ranging from 0.001 to 0.500 in 0.001 increments, along with other pieces of data. Both data sets are X-by-Y doubles. What I'm trying to do is something like... for i = 1:length(actual_latency) row = find(predicted_data(:,1) == actual_latency(i)) full_set(i,1:4) = [actual_latency(i) other_info(i) predicted_info(row,2) ... predicted_info(row,3)]; end ...in order to find the relevant row in predicted_data where the look up latency corresponds to the actual latency. I then use this to created an amalgamated data set, full_set. I figured this would be really simple, but the find function keeps failing by throwing up an empty matrix when looking for an actual latency that I know is in predicted_data(:,1) (as I've double-checked during debugging). Moreover, if I replace find with a for loop to do the same job, I get a similar error. It doesn't appear to be systematic - using different participant data sets throws it up in different places. Furthermore, during debugging mode, if I use find to try and find a hard-coded value of actual_latency, it doesn't always work. Sometimes yes, sometimes no. I'm really scratching my head over this, so if anyone has any ideas about what might be going on, I'd be really grateful.

    Read the article

  • Swap bits in c++ for a double

    - by hidayat
    Im trying to change from big endian to little endian on a double. One way to go is to use double val, tmp = 5.55; ((unsigned int *)&val)[0] = ntohl(((unsigned int *)&tmp)[1]); ((unsigned int *)&val)[1] = ntohl(((unsigned int *)&tmp)[0]); But then I get a warning: "dereferencing type-punned pointer will break strict-aliasing rules" and I dont want to turn this warning off. Another way to go is: #define ntohll(x) ( ( (uint64_t)(ntohl( (uint32_t)((x << 32) >> 32) )) << 32) | ntohl( ((uint32_t)(x >> 32)) ) ) val = (double)bswap_64(unsigned long long(tmp)); //or val = (double)ntohll(unsigned long long(tmp)); But then a lose the decimals. Anyone know a good way to swap the bits on a double without using a for loop?

    Read the article

  • PHP math gets crazy, need explanation, my brain is melting

    - by derei
    I know that playing with php float can give strange results if you try to add "goats + apples", but please take a look to the following case: $val = 1232.81; $p1 = 1217.16; $p2 = 15.65; $sum = $p1 + $p2; $dif = $val - $sum; echo $dif; It will give you -2.2737367544323E-13 ... yeah, ALMOST zero, but then why it doesn't say 0 ? This freaks me out big time. Please, I need some valid explanation.

    Read the article

  • Doing arithmetic with up to two decimal places in Python?

    - by user248237
    I have two floats in Python that I'd like to subtract, i.e. v1 = float(value1) v2 = float(value2) diff = v1 - v2 I want "diff" to be computed up to two decimal places, that is compute it using %.2f of v1 and %.2f of v2. How can I do this? I know how to print v1 and v2 up to two decimals, but not how to do arithmetic like that. The particular issue I am trying to avoid is this. Suppose that: v1 = 0.982769777778 v2 = 0.985980444444 diff = v1 - v2 and then I print to file the following: myfile.write("%.2f\t%.2f\t%.2f\n" %(v1, v2, diff)) then I will get the output: 0.98 0.99 0.00, suggesting that there's no difference between v1 and v2, even though the printed result suggests there's a 0.01 difference. How can I get around this? thanks.

    Read the article

  • Float Conversion Issue

    - by user1407570
    I have an issue after converted a float from a string, the result of my operation is null The NSLogs give the right value but vitesseMoyenne is equal to null -(void)setVitesseMoyenne:(float)uneDistanceTotale:(NSString*)unTempsTotal { //float tempEnFloat = [unTempsTotal floatValue]; NSLog(@"%@",unTempsTotal); float calculVitesseMoyenne = uneDistanceTotale / [unTempsTotal floatValue]; NSLog(@"%f",calculVitesseMoyenne); vitesseMoyenne = [NSString stringWithFormat:@"%f", calculVitesseMoyenne]; } Can you see what is wrong ?

    Read the article

  • Is it possible to read Fortran formatted data in Python?

    - by Werner
    I get output files from very old Fortran programs, which look like: 0.81667E+00 -0.12650E+01 -0.69389E-03 0.94381E+00 -0.11985E+01 -0.11502E+00 0.96064E+00 -0.11333E+01 -0.17616E+00 0.10202E+01 -0.12435E+01 -0.93917E-01 0.10026E+01 -0.10904E+01 -0.15108E+00 0.90516E+00 -0.11030E+01 -0.19139E+00 0.98624E+00 -0.11598E+01 -0.22970E+00 Is it possible to read this in Python and convert the numbers to "normal" floats?

    Read the article

< Previous Page | 9 10 11 12 13 14 15 16 17 18 19 20  | Next Page >