I'm trying to analyze Population Dynamics. I found some articles and read them but what kind of model i need to use. I tried Forest Fire model but i failed in modificating.
#include <stdio.h>
#include <stdlib.h>
#define MaxPopulation 10000
#define MaxChildren 10
#define maxAge 70
#define ranf() ((double) random()/(double)RAND_MAX)
I need to run a public domain code in Molecular Dynamics. I have a Knoppix 7.2 system with Geany and gcc 4.7.2-5 and g++ 4:4.7.2-1 .
I need to compile this code and create a binary but can't.
The output:
gcc -o md md.c
/tmp/ccODg4eA.o: In function `compute':
md.c:(.text+0x718): undefined reference to `sin'
md.c:(.text+0x72a): undefined reference to `pow'
md.c:(.text+0x794): undefined reference to `sin'
/tmp/ccODg4eA.o: In function `dist':
md.c:(.text+0x8f9): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
note that since this is a Public Domain code, I have not altered it. The main code:
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <math.h>
#include <string.h>
int main ( int argc, char *argv[] );
void compute ( int np, int nd, double pos[], double vel[],
double mass, double f[], double *pot, double *kin );
[code]....
I'm new to C++ and am trying to create a program to solve the problem as described in this image: [URL] .....
Here's my code. It fails to execute the main part of the problem (years, population of A & B) but works well in recognizing errors (if PopA >PopB or if growth rate of PopA<PopB)
Code:
#include <iostream>
#include <iomanip>
#include <string>
using namespace std;
int main() {
string city1, city2;
[Code] .....
I'm supposed to store the value of a countrys population. Then gather out the percentage that countrys population holds when compared with the global population.
Anyway here's the code:
Code:
#include <iostream>
long swe_pop = 9644864;
int main ()
[Code] .....
The result I'm getting is 0%.
I was under the impression that long (or long long) integers could hold high values. And that I could then divide these and answer with a float type value. Giving space for the decimals.
Write a program that will predict the size of a population of organisms. The program should ask the user for the starting number of organisms, their average daily population increase (as a percentage), and the number of days they will multiply. A loop should display the size of the population for each day.
Input Validation: Do not accept a number less than 2 for the starting size of the population. Do not accept a negative number for average daily population increase. Do not accept a number less than 1 for the number of days they will multiply.
My code works fine just up until the end.
#include <iostream>
using namespace std;
int main() {
int organisms = 0, growthRate, rate, days, amount = 0;
//int x; //for loop
[Code] .....
Am I doing this correctly? My assignment is pretty much to answer certain codes manually.
int i = 0;
while (i < 7 )
{
cout << 2 * i;
++i;
}
Does this code read as
2 * 0 = 0
2 * 1 = 2
2 * 3 = 6
2 * 4 = 8
2 * 5 = 10
2 * 6 = 12
How about the ++i part?
Write a class called MyTriangle, which models a triangle with 3 vertices, is designed as follows. It contains:
1. The MyTriangle class uses three MyPoint instances as the three vertices.
2. Three private instance variables v1, v2, v3 (instances of MyPoint), for the three vertices.
3. A constructor that constructs a MyTriangle with three points v1=(x1, y1), v2=(x2, y2), v3=(x3, y3).
4. An overloaded constructor that constructs MyTriangle given three instances of MyPoint.
5. A toString() function that returns a string description of the instance in the format "Triangle @ (x1, y1), (x2, y2), (x3, y3)".
6. A getPerimeter() function that returns the length of the perimeter in double. You should use the distance() method of MyPoint to compute the perimeter.
7. Also write a test program (called main.cpp) to test all the functions defined in the class (example of a triangle: (-2, 1), (1, 3) and (3, -3)).
class MyTriangle {
MyPoint v1;
MyPoint v2;
MyPoint v3;
public:
MyTriangle(int x1,int y1,int x2,int y2,int x3,int y3) {
[Code] .....
I would like to write a program that can analyze png files to assess whether they have any rotational symmetry.
I am aware that opencv can be used to do certain image recognition tasks, would it be appropriate for what i'm trying to do?
This program must work in linux.
I have to analyze and elaborate datas from particle energy measurements. I have a file txt like this
1 126 17 20 23 32 39 55 68 81 98 111 129 141 151 164 170 182 180 183 187 187 181 186 178 174 175 172 163 159 155 147 140 138 128 122 105 100 99 87 80 66 59 55 48 42 40 33 31 25 25 22 19 19 18 15 15 16 15 16 15 13 13 14 14 14 14 13 13 14 14 13 15 15 14 15 14 14 13 12 13 14 13 14 14 14 13 14 14 13 12 13 13 13 13 14 13 13 13 13 14 14 14 13 13 14 14 14 12 12 13 12 13 11 12 13 12 13 14 12 12 12 11 13 12 13 13 15
2 124 20 34 9 34 51 50 61 76 71 69 95 99 108 103 101 95 89 117 98 107 76 86 66 97 97 80 17 54 45 44 39 40 18 13 29 20 16 15 15 16 14 15 16 16 15 15 14 13 12 14 14 14 12 14 13 12 15 12 12 14 14 11 12 12 14 12 12 13 12 12 13 12 12 12 13 12 13 13 13 12 14 12 12 13 10 12 13 12 13 13 13 12 12 12 13 12 12 13 12 10 15 13 13 12 14 12 12 14 12 12 13 13 13 12 12 12 11 11 13 14 12 12 12 13
The first two numbers are the Particle ID and its Energy, the rest of numbers are the loss of energy(different in number for every particle).
I have to elaborate 1000 events like this and to create a function able to read every line and to count the number of the loss energy measurement.
I use ifstream to read a file text, but my problem is: my program how to understand that it's passing to the new line? I have to divided every events in Arrays of different length, so i have to count each data for every particle and then create the array.
The instruction EOF it's not good...
I would like to create program which will analyse bitmap so would need good concept to save data. I am interested about the theory and I realize that i must to think this carefully because bad concept could create insufficient memory or inefficient program. Basically I want my program work with HSV or HSL model so I would need to convert the bitmap to HSL, but I am not sure if I should convert it first and then analyse all pixels or should I start to analyse the bitmap and make the conversion to HSL during it. But my main question is what method to choose to save the data in memory.
Even that I would start with very small, it should work also with bigger image like image having 1200 or even 4200 px on height. So the program should first analyse all columns of pixels in the image so for example 1200x800 px image has 1200 columns. So I would like to know if is it possible to create such object which would have such structure like this
Obj->basicColumnData->black->columns[name]->group
and in the place of columns should be placed data for every column. I would look for groups of pixels in the column, so in the result the column x could bear e.g. 500 groups of information and every group should contain the range of pixels e.g. group 1 should contain y value from 0 to 20, group 2 should contain value from 25-27 and so on. So I would create 1200 columns bear many of groups. This would be contained in "black" or "white" member to contain the data. This is just simplified idea, but the whole object should contain next data not just basicColumnData... So there should be another members bearing information calculated from the selected data.
So my question is what kind of method of saving data use for this? Should I use heap and dynamic allocated memory or should I create custom class, which will define every member, but these members will have to be dynamic memory? With the dynamic memory is there problem that there could be not enough memory to create such big object?
how to put together a basic ray tracer which can model spheres and planes. I have an example ray tracer which I am currently pulling apart and sifting through line by line to try and understand exactly how it works. I have come to a point in the code which I am having trouble explaining adequately. It's a method of the Plane class, which is a class defining the planes in the scene. The method is called findIntersection and I believe its purpose is to return the distance between the origin of the ray and the point of intersection, it looks like this
double findIntersection(Ray ray){
Vector ray_direction=ray.getDirection();
double a = ray_direction.DotProduct(normal);
if(a==0){
return -1;
}
else{
double b=normal.DotProduct(ray.getStart()+((normal*distance).Inverse()));
return -1*b/a;
}
}
The method accepts arguments of type Ray which is a class defining rays, rays are constructed from this class by supplying two vectors, a starting vector and a direction vector, the Ray class has a method function getDirection which is used in the first line of the findIntersection function which clearly just returns the direction vector. The DotProduct method being accessed belongs to the Vector class and is a standard method for finding the dot product of two vectors. "normal" is a variable of type Vector and is used in the construction of an instance of the Plane class, along with a distance from the centre of the scene and a colour. Also, in the line double b=normal.DotProduct(ray.getStart()+((normal*distance).Inverse())); the plus sign between the two vectors is an overloaded operator which adds the two vectors in the usual mathematical way, I overloaded it for neatness.
The trouble I'm having is working out what the variables a and b are doing, what they mean geometrically and how they correspond to getting the distance between ray origin and point of intersection. Clearly if the dot product of the normal with the ray equals zero then the ray is parallel to the plane and so there is no intersection but what is a's role in the return statement.
I need to create a if else statement to check multiple model numbers (200+)... How can i build this? I basically want the user to enter their model number and if its on the list they get a approved or denied message.
So far I have this, the "if(model == 9002||1002)" doesnt seem right, it needs to basically check 200+ model numbers... am I even on the right track?
Code:
#include <iostream>
using namespace std;
int main(){
int model;
cout << "Enter model" << endl;
[Code] .....
I have done a test, I have edited with the WordPad in Windows on my Local Webserver a file banana.h which contains a list of float arrays in order to extract one array and create a text file named ObjVerts.txt I have done a lot of search in the Web in order to find a small piece of code that can read the text file and convert it to a float array GLfloat, but I did not find any. I have found a lot of piece of code that read the file and make a NSData but many of the code seem to not work. It seem that the last statement return nothing!
NSURL *myurl = [NSURL URLWithString:@"http://localhost/ObjVerts.txt"];
//NSString *mystring = [NSString stringWithContentsOfURL:myurl];
NSData *mydata = [NSData dataWithContentsOfURL:myurl];
The project is "Design and write a program to model the operation of incoming flights computer screen that is normally found at a typical small airport like Moshoeshoe I airport (if they do have one). The following provides the information that needs to be displayed about each flight:
• Airline - [string of maximum length 15] Name of the airline, eg. FlySAA
• Flight Number - [string of maximum length 5] eg. 04120
• Origin - [string of maximum length 25] Place where the flight originated from eg. Johannesburg
• Date/Time - [integers: Hour, Minute, Day, Month, Year] Arrival time of the flight
• Status - [string of maximum length 15] Whether the flight is "OnTime" or "Delayed"
