Search Results

Search found 9015 results on 361 pages for 'wireless range'.

Page 289/361 | < Previous Page | 285 286 287 288 289 290 291 292 293 294 295 296  | Next Page >

• generate random characters in c

  - by Nick

  I'm new to programming in C and have been given the task of creating a 2D array that stores random letters from A-Z using the random () function. I know how to do random numbers. nextvalue = random ( ) % 10001; but am unsure on how exactly to create a random character. I know that you can use ASCII to create a random character using the range 65 - 90 in the ASCII table. Can anyone help me come up with a solution? I would greatly appreciate it.

  Read the article

• SVN user guidelines

  - by Oliver Moran

  I have been tasked with writing a set of user guidelines for SVN for developers in my company. The guidelines are to be solely from a user perspective (e.g. commit comments, when to commit) and not from an administrative perspective (e.g. when to tag, how to structure). An administrative guideline will be written in a separate document. We are an app development house involved also in embedded development. So our developers range from HTML5 and Flash to Java and C. Some of our coding involves forking very large (millions of files) code bases. Other parts involve us engaging in ground-up development. Are there any best practices for use of SVN from a user (i.e. grunt developer) perspective?

  Read the article

• Python performance profiling (file close)

  - by user1853986

  First of all thanks for your attention. My question is how to reduce the execution time of my code. Here is the relevant code. The below code is called in iteration from the main. def call_prism(prism_input_file,random_length): prism_output_file = "path.txt" cmd = "prism %s -simpath %d %s" % (prism_input_file,random_length,prism_output_file) p = os.popen(cmd) p.close() return prism_output_file def main(prism_input_file, number_of_strings): ... for n in range(number_of_strings): prism_output_file = call_prism(prism_input_file,z[n]) ... return I used statistics from the "profile statistics browser" when I profiled my code. The "file close" system command took the maximum time (14.546 seconds). The call_prism routine is called 10 times. But the number_of_strings is usually in thousands, so, my program takes lot of time to complete. Let me know if you need more information. By the way I tried with subprocess, too. Thanks.

  Read the article

• How to move many files in multiple different directories (on Linux)

  - by user1335982

  My problem is that I have too many files in single directory. I cannot "ls" the directory, cos is too large. I need to move all files in better directory structure. I'm using the last 3 digits from ID as folders in reverse way. For example ID 2018972 will gotta go in /2/7/9/img_2018972.jpg. I've created the directories, but now I need help with bash script. I know the IDs, there are in range 1,300,000 - 2,000,000. But I can't handle regular expressions. I wan't to move all files like this: /images/folder/img_2018972.jpg -> /images/2/7/9/img_2018972.jpg I will appreciate any help on this subject. Thanks!

  Read the article

• Is it possible to scroll in isearch mode?

  - by Leo Alekseyev

  Is there a way to scroll through a document without exiting isearch mode? I have isearch-allow-scroll set to t, but that limits my scroll range to make sure the current isearch match is visible in the buffer. Ideally, I would like to be able to scroll with the mousewheel, having all the isearch matches highlighted as I scroll. I am aware of M-x occur, but a lot of the time simply being able to scroll in isearch mode would be more efficient (in addition, M-x occur does not play well with folding mode).

  Read the article

• Efficient mapping for a particular finite integer set

  - by R..

  I'm looking for a small, fast (in both directions) bijective mapping between the following list of integers and a subset of the range 0-127: 0x200C, 0x200D, 0x200E, 0x200F, 0x2013, 0x2014, 0x2015, 0x2017, 0x2018, 0x2019, 0x201A, 0x201C, 0x201D, 0x201E, 0x2020, 0x2021, 0x2022, 0x2026, 0x2030, 0x2039, 0x203A, 0x20AA, 0x20AB, 0x20AC, 0x20AF, 0x2116, 0x2122 One obvious solution is: y = x>>2 & 0x40 | x & 0x3f; x = 0x2000 | y<<2 & 0x100 | y & 0x3f; Edit: I was missing some of the values, particularly 0x20Ax, which don't work with the above. Another obvious solution is a lookup table, but without making it unnecessarily large, a lookup table would require some bit rearrangement anyway and I suspect the whole task can be better accomplished with simple bit rearrangement. For the curious, those magic numbers are the only "large" Unicode codepoints that appear in legacy ISO-8859 and Windows codepages.

  Read the article

• How to stable_sort without copying?

  - by Mehrdad

  Why does stable_sort need a copy constructor? (swap should suffice, right?) Or rather, how do I stable_sort a range without copying any elements? #include <algorithm> class Person { Person(Person const &); // Disable copying public: Person() : age(0) { } int age; void swap(Person &other) { using std::swap; swap(this->age, other.age); } friend void swap(Person &a, Person &b) { a.swap(b); } bool operator <(Person const &other) const { return this->age < other.age; } }; int main() { static size_t const n = 10; Person people[n]; std::stable_sort(people, people + n); }

  Read the article

• Ruby (with Rails) convert a string of time into seconds?

  - by Ryan

  So, I've got a string of time... something along the lines of '4 hours' '48 hours' '3 days' '15 minutes' I would like to convert those all into seconds. For '4 hours', this works fine Time.parse('4 hours').to_i - Time.prase('0 hours').to_i => 14400 # 4 hours in seconds, yay However, this doesn't work for 48 hours (outside of range error). It also does not work for 3 days (no information error), etc. Is there a simple way to convert these strings into seconds?

  Read the article

• Are there any real life uses for the Java byte primitive type?

  - by Thorbjørn Ravn Andersen

  For some inexplicable reason the byte primitive type is signed in Java. This mean that valid values are -128..127 instead of the usual 0..255 range representing 8 significant bits in a byte (without a sign bit). This mean that all byte manipulation code usually does integer calculations and end up masking out the last 8 bits. I was wondering if there is any real life scenario where the Java byte primitive type fits perfectly or if it is simply a completely useless design decision? EDIT: The sole actual use case was a single-byte placeholder for native code. In other words, not to be manipulated as a byte inside Java code.

  Read the article

• Help with implementing a function to change size of dynamic array

  - by iRobot

  I'm trying to write a function that will change the size of a dynamic array to a new size. In my header file, I have: Image **images; //pointer to a dynamic array of image pointers int maximum; //size I want to do this by allocating a new array and copying the values over without changing their indices. If there are non-null pointers outside the range newmax, then we cant do this. So heres what I have: There are no compilation or runtime errors. However, I find that the new array isnt getting sized right. When I run the following test case: I should get an index out of bounds error, but instead the system lets it slide. Can anyone see the mistake? I've looked for hours but cant find anything.

  Read the article

• Why can't I project ToString() in VB?

  - by Martinho Fernandes

  If you try to compile the query below in Visual Basic .NET, it fails. From x In {1, 2} Select x.ToString() The error given by the compiler is: Range variable name cannot match the name of a member of the 'Object' class. There is nothing wrong with the equivalent C# query, though: from x in new[]{1, 2} select x.ToString() This does not happen with the ToString overload that takes a format (it is a member of Int32, not Object). It does happen with other members of Object, as long as they don't take an argument: with GetType and GetHashCode it fails; with Equals(object) it compiles. Why is this restriction in place, and what alternatives can I use?

  Read the article

• How to pass multiple params to function in python?

  - by user1322731

  I am implementing 8bit adder in python. Here is the adder function definition: def add8(a0,a1,a2,a3,a4,a5,a6,a7,b0,b1,b2,b3,b4,b5,b6,b7,c0): All function parameters are boolean. I have implemented function that converts int into binary: def intTObin8(num): bits = [False]*8 i = 7 while num >= 1: if num % 2 == 1: bits[i] = True else: bits[i] = False i = i - 1 num /= 2 print bits return [bits[x] for x in range(0,8)] I want this function to return 8 bits. And to use this two functions as follows: add8(intTObin8(1),intTObin8(1),0) So the question is: How to pass 8 parameters using one function?

  Read the article

• compare date split across colums

  - by alex-tech

  Greetings. I am querying tables from Microsoft SQL 2008 which have date split across 3 columns: day, month and year. Unfortunately, I do not have control over this because data is coming in to the database daily from a 3rd party source in that format. I need to add between to a where clause so user can pull records within a range. Would be easy enough if date was in a single column but finding it nearly impossible when its split across three columns. To display the date, I am doing a CAST( CAST(year as varchar(4)) + '-' + CAST(month as varchar(2)) + '-' + CAST(day as varchar(2)) as date) AS "date"` in a select. I tried to put it as a parameter for datediff function or just the regular between but get no results. Thanks for any help.

  Read the article

• Problems with sys.stdout.write() with time.sleep() in a function

  - by philipjkim

  What I wanted is printing out 5 dots that a dot printed per a second using time.sleep(), but the result was 5 dots were printed at once after 5 seconds delay. Tried both print and sys.stdout.write, same result. Thanks for any advices. import time import sys def wait_for(n): """Wait for {n} seconds. {n} should be an integer greater than 0.""" if not isinstance(n, int): print 'n in wait_for(n) should be an integer.' return elif n < 1: print 'n in wait_for(n) should be greater than 0.' return for i in range(0, n): sys.stdout.write('.') time.sleep(1) sys.stdout.write('\n') def main(): wait_for(5) # FIXME: doesn't work as expected if __name__ == '__main__': try: main() except KeyboardInterrupt: print '\nAborted.'

  Read the article

• Gradient boosting predictions in low-latency production environments?

  - by lockedoff

  Can anyone recommend a strategy for making predictions using a gradient boosting model in the <10-15ms range (the faster the better)? I have been using R's gbm package, but the first prediction takes ~50ms (subsequent vectorized predictions average to 1ms, so there appears to be overhead, perhaps in the call to the C++ library). As a guideline, there will be ~10-50 inputs and ~50-500 trees. The task is classification and I need access to predicted probabilities. I know there are a lot of libraries out there, but I've had little luck finding information even on rough prediction times for them. The training will happen offline, so only predictions need to be fast -- also, predictions may come from a piece of code / library that is completely separate from whatever does the training (as long as there is a common format for representing the trees).

  Read the article

• TCP Scanner Python MultiThreaded

  - by user1473508

  I'm trying to build a small tcp scanner for a netmask. The code is as follow: import socket,sys,re,struct from socket import * host = sys.argv[1] def RunScanner(host): s = socket(AF_INET, SOCK_STREAM) s.connect((host,80)) s.settimeout(0.1) String = "GET / HTTP/1.0" s.send(String) data = s.recv(1024) if data: print "host: %s have port 80 open"%(host) Slash = re.search("/", str(host)) if Slash : netR,_,Wholemask = host.partition('/') Wholemask = int(Wholemask) netR = struct.unpack("!L",inet_aton(netR))[0] for host in (inet_ntoa(struct.pack("!L", netR+n)) for n in range(0, 1<<32-Wholemask)): try: print "Doing host",host RunScanner(host) except: pass else: RunScanner(host) To launch : python script.py 10.50.23.0/24 The problem I'm having is that even with a ridiculous low settimeout value set, it takes ages to cover the 255 ip addresses since most of them are not assigned to a machine. How can i make a way faster scanner that wont get stuck if the port is close.MultiThreading ? Thanks !

  Read the article

• jquery UI slider not working in Safari.

  - by Joe

  so i have the below code, which I think is fine: jQuery( function() { jQuery("#slider-vertical").slider( { orientation :"vertical", range :"min", min :0, max :100, value :50, slide : function(event, ui) { jQuery("#amount").val(ui.value); var movie = thisMovie('ClusterFlash'); fromScroll = jQuery("#amount").val(); if (movie) { currentSentiment = ((100 - fromScroll) / 100); movie.sentimentChange(currentSentiment); } } }); }); the 'movie' var above calls the following function, which seems to be where my problem is. function thisMovie(movieName) { if (navigator.appName.indexOf("Microsoft") != -1) { return window[movieName]; } if(document[movieName].length != undefined) { return document[movieName][1]; } return document[movieName]; } Any help would be appreciated. Thank

  Read the article

• Obtaining a timestamp every minute from a database

  - by soumen

  This is my table structure: +------------+-----------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +------------+-----------+------+-----+---------+-------+ | uid | char(255) | NO | MUL | NULL | | | cid | char(255) | NO | MUL | NULL | | | ip_address | char(15) | NO | | NULL | | | user_agent | char(255) | YES | | NULL | | | open_date | datetime | NO | MUL | NULL | | | referrer | char(255) | YES | | NULL | | | environ | text | YES | | NULL | | | country | char(255) | NO | MUL | NULL | | +------------+-----------+------+-----+---------+-------+ I want to get a timestamp every minute within a range. select DATE_ADD(open_date,interval 1 minute) as m from open_track.camp_open where open_date between "2009-05-13 00:00:00" and "2009-05-13 23:59:59" limit 10; outputs +---------------------+ | m | +---------------------+ | 2009-05-13 00:01:01 | | 2009-05-13 00:01:02 | | 2009-05-13 00:01:03 | | 2009-05-13 00:01:03 | | 2009-05-13 00:01:04 | | 2009-05-13 00:01:05 | | 2009-05-13 00:01:06 | | 2009-05-13 00:01:08 | | 2009-05-13 00:01:08 | | 2009-05-13 00:01:09 | +---------------------+ Please advise me.

  Read the article

• C# chart control Performance with large amounts of data

  - by user3642115

  I am using a chart control with a range bar graph to basically make a gantt chart for lots of people and lots of projects, say about 1000 total series. The issue that I am running in to is that once I have all my data added to the chart, which takes some time but that is to be expected, and I go to scroll down on my graph it freezes the whole application and takes a while before it unfreezes and scrolls down. Is there any way to improve the performance of this? I tried adding the graph to a panel and growing the graph size dynamically and then scrolling down from the panel but that cause a whole plethora of other issues. Any tips for speeding this up? I don't think it is my code as it has already finished running when this issue happens. Thanks.

  Read the article

• Do something when phone reaches a set of location?

  - by Pentium10

  I have a list of coordinates in the database identified as POI. For a city could be 100 records. I would like to get notified when the phone gets in 150 meters range of one of the location. The location coordinates too has an error/radius, usually 10 to 100meters. Since I don't find it good to add each location(could be hundreds) for a trigger, how can I optimize the wake-up code? Also do I have options to remove a previously setup notification from the queue?

  Read the article

• Optimal strategy to make a C++ hash table, thread safe

  - by Ajeet

  (I am interested in design of implementation NOT a readymade construct that will do it all.) Suppose we have a class HashTable (not hash-map implemented as a tree but hash-table) and say there are eight threads. Suppose read to write ratio is about 100:1 or even better 1000:1. Case A) Only one thread is a writer and others including writer can read from HashTable(they may simply iterate over entire hash table) Case B) All threads are identical and all could read/write. Can someone suggest best strategy to make the class thread safe with following consideration 1. Top priority to least lock contention 2. Second priority to least number of locks My understanding so far is thus : One BIG reader-writer lock(semaphore). Specialize the semaphore so that there could be eight instances writer-resource for case B, where each each writer resource locks one row(or range for that matter). (so i guess 1+8 mutexes) Please let me know if I am thinking on the correct line, and how could we improve on this solution.

  Read the article

• Inserting timestamp value in SQL Server

  - by JPro

  I am trying to copy data from my MYSQL table to SQL Server using PHP. I have a TimeStamp value that needs to be copied. While I am trying to copy the fields, it gave an error that timestamp value cannot be inserted. Is there any way to insert the timestamp value? Is it is not possible, then declaring the column as nvarchar will insert the timestamp, but will I be able to search the data in a date range? Can anyone please clarify my doubt? Thanks.

  Read the article

• Scale 2D coordinates and keep their relative euclidean distances intact?

  - by eiaxlid

  I have a set of points like: pointA(3302.34,9392.32), pointB(34322.32,11102.03), etc. I need to scale these so each x- and y-coordinate is in the range (0.0 - 1.0). I tried doing this by first finding the largest x value in the data set (maximum_x_value), and the largest y value in the set (minimum_y_value). I then did the following: pointA.x = (pointA.x - minimum_x_value) / (maximum_x_value - minimum_x_value) pointA.y = (pointA.y - minimum_y_value) / (maximum_y_value - minimum_y_value) This changes the relative distances(?), and therefore makes the data useless for my purposes. Is there a way to scale these coordinates while keeping their relative distances the intact?

  Read the article

• Sort vector<int>(n) in O(n) time using O(m) space?

  - by Adam

  I have a vector<unsigned int> vec of size n. Each element in vec is in the range [0, m], no duplicates, and I want to sort vec. Is it possible to do better than O(n log n) time if you're allowed to use O(m) space? In the average case m is much larger than n, in the worst case m == n. Ideally I want something O(n). I get the feeling that there's a bucket sort-ish way to do this: unsigned int aux[m]; aux[vec[i]] = i; Somehow extract the permutation and permute vec. I'm stuck on how to do 3. In my application m is on the order of 16k. However this sort is in the inner loops and accounts for a significant portion of my runtime.

  Read the article

• Implementing an iterator over binary tree using C++ 11

  - by user1459339

  I would like to create an iterator over the binary tree so as to be able to use range-based for loop. I understand I ought to implement the begin() and end() function first. Begin should probably point to the root. According to the specification, however, the end() functions returns "the element following the last valid element". Which element (node) is that? Would it not be illegal to point to some "invalid" place? The other thing is the operator++. What is the best way to return "next" element in tree? I just need some advice to begin with this programming.

  Read the article

< Previous Page | 285 286 287 288 289 290 291 292 293 294 295 296  | Next Page >