When I try to compile this code:
#include <math.h>
int main (void) {
double x, y;
x = 2;
y = sqrt(x);
return 0;
}
With the command:
$ gcc test.c
I got this message:
/tmp/cc5QZmCN.o: In function 'main':
test.c:(.text+0x16): undefined reference to 'sqrt'
collect2: error: ld returned 1 exit status
I tried this on a fresh jessie install. I have the same problem on wheezy.
Code:
#include <iostream>
using namespace std;
[code]...
i want to know how to access setdest function in ns2
View 1 Replies View Relatedit possible to access main program function from dynamicallyinked library in c language?For example:main.c:
Code:
#include<stdio.h>
void func()
[code]...
Code:
Why are basic math problems returning 0? I know that Integers can only hold whole numbers, and it had the exact same problem when I used floats. I am using GCC 4.4.4.
I've started programming in c recently . following are the details about scene:
* vim is editor and program is compiled in gcc whenever a program involving math function appears it gives error i.though math.h is included in header file compiler complains about it it gives error of unrecognized function that math function like sqrt, etc question is how to connect math.h to a program.
Here is my situation:I have a series of .plt files that are geared for a device that has it's xy origin at the lower left of the paper however some devices use the center of the paper as it's origin in a piped shell script how can I convert this file to a center origin plot file?Here are some knowns: the existing file always Lower Left 0.0 the existing file max xy is the page upper right x.x the desired output file must have it's 0.0 at the exact center of page (page size will vary). Ideas: Based on the sample files included maybe use PU and PD as the triggers for inputs to be calculated as any other commands have nothing to do with coordinates.
View 14 Replies View RelatedI wrote a perl script to feed information to our load balancer:
Code:
#!/usr/bin/perl
#
use strict;
#use warnings;
#
#
use Net::SSH::Perl;
my $user="bluethundr";
my $pass="secret";
my $dir="$ENV{HOME}/data";
open (LBVSERVERS), '<', "$dir/lb-vserver" or die "Couldn't open file: $!";
open (CSVSERVERS), '<', "$dir/cs-vserver" or die "Couldn't open file: $!";
my $ssh = Net::SSH::Perl->new("10.50.0.1");
$ssh->login("$user", "$pass");
print " .....
I need to be able to install the Math::Pari CPAN module in order to accomodate the Net::SSH CPAN module. The prereqs are installed:
Code:
cpan> install Net::FTP
Net::FTP is up to date.
cpan> install LWP::UserAgent
LWP::UserAgent is up to date.
But when I either try to install or force install Math::Pari this is what I get:
Code:
cpan> install Math::Pari
Running install for module Math::Pari
Running make for I/IL/ILYAZ/modules/Math-Pari-2.01080604.tar.gz
Checksum for /home/bluethundr/.cpan/sources/authors/id/I/IL/ILYAZ/modules/Math-Pari-2.01080604.tar.gz ok
Math-Pari-2.01080604/ .....
CPAN.pm: Going to build I/IL/ILYAZ/modules/Math-Pari-2.01080604.tar.gz
Did not find GP/PARI build directory around.
Do you want to me to fetch GP/PARI automatically?
(If you do not, you will need to fetch it manually, and/or direct me to the directory with GP/PARI source via the command-line option paridir=/dir)
Make sure you have a large scrollback buffer to see the messages, or 'tee' the STDOUT/STDERR to a file.
Fetch? (y/n, press Enter) y
Getting GP/PARI from ftp://megrez.math.u-bordeaux.fr/pub/pari/unix/
Cannot list (Failed to establish connection.
): at utils/Math/PariBuild.pm line 319, <STDIN> line 1.
Can't fetch file with Net::FTP, now trying with LWP::UserAgent...
You do not have LWP::UserAgent and/or HTML::LinkExtor installed, cannot download, exiting...
I am trying to map the coordinates of a grid.
Code:
R=7 # number of rows (lines)
C=6 # number of columns
X=200 # initial horizontal location
Y=100 # initial vertical location
[code]....
I am doing some Linux kernel programming for my research project. I need to record the timestamp (by using cpuid and rdtsc) when an interrupt handler (top half) is first invoked. Due to the time critical nature of the problem itself, I have to do the timestamping inside the interrupt handler itself (the first operation when the handler is called). However, I understand that tasks that are not so time critical should be deferred to a tasklet function (bottom half) for processing because other interrupts are disabled in a (top-half) interrupt handler. I am currently out of idea on how I can pass the timestamp information that I have obtained in the interrupt handler to the corresponding tasklet function.
View 2 Replies View RelatedI'm looking for a way to launch "TRIM" commands to a SSD drive myself, from a c++ code I'm going to write, for flash erasing an SSD drive (and not to wait for others things that "should do it automatically in some circumstances if this or this, this and this have been enabled and [..]" but will never tell me if it worked or not
I know there is thousands of complicated ways to test and check if it worked, and also software that needs money to do so, that's why I just want to call myself the TRIM functions and read the return value (like true or false) in order to know if it worked !
Where I can find the c++ call that could permit me to do so ? I heard about the GLibC that gives a way to access every user space function related to Linux Kernel (poll, select and others) as standard c++ functions, I suppose that, if there is a way, it will be on the GLibC but how to find it ?
I'm using ubuntu 9.04;Is there a complete library for C++ programming in ubuntu like "MSDN"?!hen using "Vim", I want to access a function's complete definition such as it's header file, library description and parameters, etc.Is it necessary to install something from repository to obtain such a documentation? And what would be the command to access a function's description in "vim"?
View 1 Replies View RelatedI want to declare a function in a function, but had no success till now, see the error code below and visit the project at sourceforge
[Code]...
I looked on the net for such function or example and didin't find anything, thus after having made one i guess it would be legitimate to drop it to see what others thinks of it.
#!/bin/bash
addelementtoarray()
{
local arrayname=$1
[code]....
fit a surface i.e. W(x,y) using svdfit() provided by "Numerical Recipes in C". svdfit() is written for curve fitting and not for surface fitting.But one can use svdfit(), as claimed by authors of NR book, to do surface fitting. On page 680 of NR book, authors have given a hint on how to use svdfit() for fitting a surface. But I have not understood it.This link may be helpful (Chapter 15 th is relevant here.):[URL]This is my problem:
Code:
I have a set of 100 numbers. I want to fit a 2-Dimensional function W(x,y) to these numbers.
[code]....
As per my knowledge, one can use systemcall to call the driver functions for example using open, close... Now is there any way to call driver functions directly from application without using system call?
View 4 Replies View RelatedI have a MySQL database running on my local server, which I currently access via laptop, desktop using HTML/PHP.I want to re-write in HTML5, I have gone through a couple of HTML5 tutorials but cannot figure out the database interface. The best match I can find is Server-Sent Events, is this the best way forward? What about writing to the database? I have found several suggestions using Web SQL database but I don't think this is suitable as my database is also accessed from Python code on the server.
View 5 Replies View RelatedI just built a VMWare VM from the Fedora 13 DVD - 64 bit. It now wants to do 385 updates so I let it download all of the rpms. As it starts to do the install I get a Transaction Error to the effect
Quote:
Test Transaction Errors: installing package kernel-2.6.34.6-47.fc13.x86_64 needs 8MB on the /boot filesystem
System monitor shows that I have 19.7 MiB available on /boot - so what is going on?
I have a question about calling an asm function from C....It doesn't work unless I create an asm variable to hold the value of the function in....Why?Here's the code that doesn't work...
asmfile.s - version one Code: .section .data
mydata: .ascii "this is the message!
.equ mylen, . - mydata
[code]...
I want to use backtrace() function to debug a crash issue. I tried this sample code to see how backtrace works. backtrace() function always returns 0 with the below code. Is there any kernel configuration that needs to be set for proper working of backtrace?
#include <execinfo.h>
#include <stdio.h>
#include <stdlib.h>
/* Obtain a backtrace and print it to stdout. */
void
print_trace (void)
[Code]...
Can you offer me the code about fmod() in C. I want to know how this function work, i am very interested in it because i have no idea to implement it, i want to know... how to write the function... not 'how to use the function' can anyone post the source codes of this function here?
View 6 Replies View Relatedi have an open source application that was developed in C++ (it uses objects and namespaces all over the place). I also have another application that was developed in C. Now i am trying to insert the code made in C into C++ application, but when i do that , i get this error on compilation of the source code:
Code:
error: 'mpi_init_vars' was not declared in this scope the function mpi_init_vars() is not part of object oriented programming and it doesn't belong to any scope, it was compiled into an object file and i am linking it with all objects of C++ application.
How can invoke the C function from C++ object oriented code?
I am trying to build a function inside a script.
Code:
#!/bin/sh
#System commands and other configurable.
IPT=/sbin/iptables
IP6T=/sbin/ip6tables
IPST=/usr/sbin/ipset
MODP=/sbin/modprobe
GET=/usr/bin/wget
INT_NET=192.168.1.0/24 .....
I can find lots of tutorials in how to use if, then, else. However, how do I define a variable inside the function?
SEE>>
Code:
for c in $ISO
Also, am I using the 'test' command correctly( -/+ week as valid test)?
I am doing a web site program and what I need is to call a C program in the PHP cloud.Do u think it would be possible? The web site would get the user input from PHP UI and pass to the C program , the C program would process the function with the user input and output the a PHP page.
View 2 Replies View RelatedI ask if a c++/c function is able to know its name from inside itself:
example:
Code:
int funct1(int a,b)
{
printf("%s ",funct_name());
}
or with a trick.
Code:
#!/bin/ksh
(...)
# FILL UP PARTITION
diskfillerfunction () {
[Code]....
Test 15: fill up partition /usr/bin/time: cannot run diskfillerfunction: No such file or directory
I am obviously omitting (...) a lot of the code, but the relevant part is all there. How do I 'time' a function?
I wrote a spinner in Perl and when I did a spinner in shell I could just run the subroutine in the background.
[code]...
In Perl, how do you run a function in a background and get the PID for that? I know PID in Perl is $$
I know what is the functionality of the sleep() method.
for(i = 0; i < length; i++){
sleep(1000);
printf("%c
", message[i]);
}
Result :every print of the message will be takes 1000sec of gap but i want to know why wee need to use the Sleep function. where exactly it is useful
On this link [URL]4 a return type is defined
Code:
return ((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG);
What is the above function returning.I am not clear with definition of what is being returned in the above code.
i want to compile function c in java and compile library is success.. when i call the library in java and error is :
Exception in thread "main" java.lang.UnsatisfiedLinkError: no libfunc.so in java.library.path
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1689)
at java.lang.Runtime.loadLibrary0(Runtime.java:823)
at java.lang.System.loadLibrary(System.java:1028)
[Code]....