Script started on Tue 16 Apr 2002 10:13:00 AM EDT
king(1)# cat block.c
/* Chapter 2, Exercise #2
*/
#include <stdio.h>
#define G 9.8 /* gravitational acceleration, m/s^2 */

int main(void)
{
  double ma,mb, /* masses, kg */
         mu,    /* coefficient of friction, dimensionless */
         a;     /* acceleration, m/s */

  printf("Give two masses in kg: ");
  scanf("%lf %lf",&ma,&mb);
  printf("Give coefficient of friction for horizontal mass: ");
  scanf("%lf",&mu);
  printf("\nPART A:\n");
  a = (ma-mu*mb)*G/(ma+mb);
  printf("The acceleration of the two masses is %.2lf m/s^2.\n",a);
  printf(
"NOTE: Max coefficient of friction for which block will move is: %.2lf\n",
  ma/mb);
  printf("\nPART B:\n");
  printf("For these same two masses hung over a frictionless pulley,\n");
  printf("the acceleration of the \"a\" mass is %.2lf m/s^2.\n",
         (ma-mb)*G/(ma+mb));
  printf("NOTE: A positive number indicates downward acceleration.\n");
  
  return 0; 
}
king(2)# cc block.c
king(3)# a.out
Give two masses in kg: 5 10
Give coefficient of friction for horizontal mass: .3

PART A:
The acceleration of the two masses is 1.31 m/s^2.
NOTE: Max coefficient of friction for which block will move is: 0.50

PART B:
For these same two masses hung over a frictionless pulley,
the acceleration of the "a" mass is -3.27 m/s^2.
NOTE: A positive number indicates downward acceleration.
king(4)# cat bmi.c
/* Chapter 2, #18, body mass index
*/
#include <stdio.h>
#define POUNDS_TO_KG 0.4536 /* Note specification of units for user input */
#define INCHES_TO_M 0.0254
#define A_F 1.667 /* constants defined for modified BMI (BMI') */
#define A_L 0.833

int main(void)
{
  double weight,height,body_fat,bmi,bmi_1;
  double fat_weight,lean_weight;

/* NOTE: To print the character "%", use %%. This is required because
   a single % is interpreted by C as the start of a conversion specifier. */
  printf("Give weight (pounds), height (inches), body fat (%%): ");
  scanf("%lf %lf %lf",&weight,&height,&body_fat);
/* unit conversions -- note optional use of compound assignment operators */
  weight*=POUNDS_TO_KG;
  height*=INCHES_TO_M;
  body_fat/=100.; /* Convert from percent to fraction. */
  
  bmi=weight/height/height;
  fat_weight=body_fat*weight;
  lean_weight=(1.-body_fat)*weight;
  bmi_1=(A_F*fat_weight+A_L*lean_weight)/height/height;/* or /(height*height) */
  
  printf("BMI = %.1lf, modified BMI = %.1lf\n",bmi,bmi_1);
 
  return 0;
}
king(5)# cc bmi.c
king(6)# a.out
Give weight (pounds), height (inches), body fat (%): 200 75 15
BMI = 25.0, modified BMI = 24.0
king(7)# cat angles.c
#include <stdio.h>
#define FILENAME "angles.dat"
double convert(int deg,int min,int sec);

int main(void)
{
  int deg,min,sec,status;
  double degrees;
  FILE *in;

  in=fopen(FILENAME,"r");
  while (1) {
    status=fscanf(in,"%d:%d:%d",&deg,&min,&sec);
    if (status == EOF) break;
    degrees=convert(deg,min,sec);
    printf("%02i:%02i:%02i = %lf degrees\n",deg,min,sec,degrees);
  }
  return 0;
}
double convert(int deg,int min,int sec) {
  return (double)deg+min/60.+sec/3600.;
}
king(8)# cat angles.dat
30:15:04
09:15:09
king(9)# cc angles.c
king(10)# a.out
30:15:04 = 30.251111 degrees
09:15:09 = 9.252500 degrees
king(11)# cat speed.c
#include <stdio.h>
#define FILENAME "speed.dat"

void main(void)
{
  float time,miles_per_hour,feet_per_second,meters_per_second;
  const float miles_to_meters=5280.*12.*.0254;
  const float hours_to_seconds=3600.;
  const float miles_to_feet=5280.;
  int status;
  FILE *in;

  in=fopen(FILENAME,"r");
  while (1) {
    status=fscanf(in,"%f",&time);
    if (status == EOF) break;
    printf("Time to run one mile (seconds): %.2f\n",time);
    miles_per_hour=hours_to_seconds/time;
    meters_per_second=miles_per_hour*miles_to_meters/hours_to_seconds;
    feet_per_second=miles_per_hour*miles_to_feet/hours_to_seconds;
  printf(
"meters per second = %.2f\nfeet per second = %.2f\nmiles per hour = %.2f\n",
          meters_per_second,feet_per_second,miles_per_hour);
  }
  fclose(in);
}
king(12)# cat speed.dat
240
480
king(13)# cc speed.c
king(14)# a.out
Time to run one mile (seconds): 240.00
meters per second = 6.71
feet per second = 22.00
miles per hour = 15.00
Time to run one mile (seconds): 480.00
meters per second = 3.35
feet per second = 11.00
miles per hour = 7.50
king(15)# exit
king(16)# 
script done on Tue 16 Apr 2002 10:14:16 AM EDT