Homework Number 6

/*  This program determines the distance between two points    */
/*  that are specified with latitude and longitude values      */
/*  that are in the Northern Hemisphere.                       */
#include <stdio.h>
#include <math.h>
#define PI 3.141593
int main(void)
{
/*  Declare variables and function prototype.  */
double lat1, long1, lat2, long2;
char again = 'y',lat1_d, long1_d, lat2_d, long2_d;
double gc_distance(double lat1,double long1,
double lat2,double long2);


/*  Get locations of two points.  */
while (again == 'y'){
printf("Enter latitude (N/S)and longitude (E/W) ");
printf("for location 1: \n");
scanf("%lf %s %lf %s",&lat1, &lat1_d, &long1, &long1_d);
if (lat1_d == 's'||'S'){
 lat1 = -lat1;
}
if (long1_d == 'w'||'W'){
 long1 = -long1;
}
printf("Enter latitude (N/S) and longitude (E/W) ");
printf("for location 2: \n");
scanf("%lf %s %lf %s",&lat2, &lat2_d, &long2, &long2_d);
if (lat2_d == 's'||'S'){
 lat2 = -lat2;
}
if (long2_d == 'w'||'W'){
 long2 = -long2;
}
/*  Print great circle distance.  */
printf("Great Circle Distance: %.0f miles \n",
gc_distance(lat1,long1,lat2,long2));
printf("Again? (y/n)");
scanf(" %s", &again);
/*  Exit program.  */
}
return 0;
}
/*–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––*/
/*  This function computes the distance between two            */
/*  points using great circle distances.                       */
double gc_distance(double lat1,double long1,
double lat2,double long2)
{
/*  Declare variables.  */
double angle(double x1, double y1, double z1, double x2, double y2,double z2);
double rho, phi, theta, gamma, dot, dist1, dist2,x1, y1, z1, x2, y2, z2;
/*  Convert latitude,longitude to rectangular coordinates.  */
rho = 3960;
phi = (90 - lat1)*(PI/180.0);
theta = (360 - long1)*(PI/180.0);
x1 = rho*sin(phi)*cos(theta);
y1 = rho*sin(phi)*sin(theta);
z1 = rho*cos(phi);
phi = (90 - lat2)*(PI/180.0);
theta = (360 - long2)*(PI/180.0);
x2 = rho*sin(phi)*cos(theta);
y2 = rho*sin(phi)*sin(theta);
z2 = rho*cos(phi);
/*  Compute angle between vectors.  */
gamma = angle(x1, y1, z1, x2, y2, z2);
/*  Compute and return great circle distance.  */
return gamma*rho;
}
double angle(double x1, double y1, double z1, double x2, double y2, double z2){
double cos_gamma, gamma;
cos_gamma = ((x1*x2) + (y1*y2) + (z1*z2))/(sqrt(x1*x1 + y1*y1 + z1*z1)*sqrt(x2*x2 + y2*y2 + z2*z2));
gamma = acos(cos_gamma);
return gamma;
}


ARDUINO PIR AND PHOTO SENSOR SKETCH
const int LED=8;//The LED is connected to pin 9
const int PIR=2;//The PIR is connected to pin 2
const int photo = 0;
int val = 0;
int counts = 0;
void setup()
{
 pinMode(LED, OUTPUT);
 pinMode(PIR, INPUT);
 pinMode(photo, INPUT);
 Serial.begin(9600);
}
void loop()
{
 Serial.println(analogRead(photo));
 if (digitalRead(PIR) == LOW && analogRead(photo) >= 135)
 {
  digitalWrite(LED, LOW);
 }
 if (digitalRead(PIR) == HIGH && analogRead(photo) >= 135){
  digitalWrite(LED, HIGH);
  counts = counts+1;

 }
 if (digitalRead(PIR) == LOW && analogRead(photo) <= 135){
  int steps = 0;
  while (steps < counts){
    digitalWrite(LED, HIGH);
    delay(100);
    digitalWrite(LED, LOW);
    delay(100);
  }
 }
}

Comments

Post a Comment

Popular posts from this blog

Seismic Code

/* determines the times of possible seismic events. */ #include <stdio.h> #define FILENAME "seismic1.txt" #define MAX_SIZE 1000 float THRESHOLD = 0; int x = 0; int main(void) { /* Declare variables and function prototypes. */ while(THRESHOLD <=2 1){ printf("Enter Threshold: \n"); scanf(" %f ", &THRESHOLD); printf("Threshold: %f \n", THRESHOLD); } int k, npts, short_window, long_window; double sensor[MAX_SIZE], time_incr, short_power, long_power, ratio; FILE *file_ptr; double power_w(double *ptr,int n); /* Read sensor data file. */ file_ptr = fopen(FILENAME,"r"); if (file_ptr == NULL) printf("Error opening input file. \n"); else { fscanf(file_ptr,"%d %lf",&npts,&time_incr); if (npts > MAX_SIZE) printf("Data file too large for array. \n"); else { /* Read data into an array. */ for (k=0; k<=npts-1; k++) fscanf(file_ptr,"%l...
Read more

Strings

#include <stdio.h> #include <string.h> int main(void) { /* Declare and initialize variables. */ int count=0; int choice = 0; int l_l, l_s; char long_str[80]; char short_str[79]; char *ptr1=long_str, *ptr2=short_str; while (choice != 1 && choice != 2){ printf( "1. read from file \n OR 2. input longstring "); scanf(" %i", &choice); } printf(" \n"); if( choice == 1) { FILE *file; file = fopen("longstring.txt", "r"); if(file){ fgets(long_str, 80, file); } fclose(file); } if (choice == 2){ printf("Print the long string: \t"); scanf("%s", &long_str); } printf("Print short string: \t"); scanf("%s", &short_str); l_l = strlen(long_str); l_s = strlen(short_str); printf("Original Long String: "); for (int i =0;i<=l_l; i++){ printf("%c", long_str[i]); if(((int)long_str[i]) < 97){ long_str[i] = (cha...
Read more

BMP180 Code + Library to SD card

#include <Wire.h> #include <SD.h> #include "BMP180Lib.c" #define BMP180_ADDRESS 0x77 // I2C address of BMP180 // Read 1 byte from the BMP180 at 'address' // Add these to the top of your program const float p0 = 101325; // Pressure at sea level (Pa) float altitude; const int CS_PIN =10; char bmp180Read(unsigned char address) {  unsigned char data;  Wire.beginTransmission(BMP180_ADDRESS);  Wire.write(address);  Wire.endTransmission();  Wire.requestFrom(BMP180_ADDRESS, 1);  while(!Wire.available())  ;  return Wire.read(); } // Read 2 bytes from the BMP180 // First byte will be from 'address' // Second byte will be from 'address'+1 int bmp180ReadInt(unsigned char address) {  unsigned char msb, lsb;  Wire.beginTransmission(BMP180_ADDRESS);  Wire.write(address);  Wire.endTransmission();  Wire.requestFrom(BMP180_ADDRESS, 2);  while(Wire.available()<2)  ;  msb = Wire....
Read more