Input: The program should prompt the user to enter the name of two binary files.
ID: 3540527 • Letter: I
Question
Input: The program should prompt the user to enter the name of two binary files. Each
file contains a series of double-precision values; one represents a series of resistance
values, while the other contains the corresponding voltage drop across those resistors.
Note that:
-If the user enters the name of a file that cannot be opened, print an error
message and repeat the prompt for the name.
- You may assume that each input file holds the same number of values, and that
number will be no more than 20.
- After reading each file name, the program should read the contents of the file into
an array that stores these values. Look at the output test files on the course web
page (r1v1_out.txt, r2v2_out.txt, r3v3_out.txt) to see a list of the
values in each input file.
- If an error occurs when reading a file, print an error message and exit the
program.
- Note that reaching the end of the file without reading the maximum
amount of data is not an error. If you attempt to read 10 values and only
get 5, for example, the remainder of the program should work strictly with
those 5 values.
The program should also prompt for the name of a file to store your output, which is
described below.
Output: After reading the input files, your program should print the following
information:
- A table of the resistance/voltage pairs read from the input files.
- Each quantity should be shown using 2 decimal places.
- You may assume the maximum resistance is 99,999.99 ohms.
- You may assume the minimum and maximum voltages are -99.99 and
99.99 volts, respectively.
- A separate table showing the minimum, maximum, and average values for three
quantities: the voltage drops, current flow, and power consumption across all
resistors. Note that:
- Voltage should be printed using 2 decimal places; current and power
should be printed using 4.
-You should calculate the current and power for each pair of R/V values
and store each number in an appropriate array. For example, if the
resistance, voltage, and current values are stored in arrays res[],
voltage[], and current[], then current[0] is based on res[0]
and voltage[0].
-To calculate current, use the equation I (current) = V / R
- To calculate power, use the equation P = V * I
- After filling the current and power arrays, you can find the minimum,
maximum, and average value in each array before printing.
I don't understand how to work with a program that uses files such as open and closing files.
test files to use : http://tinyurl.com/kzkyc6r
Example of Output:
Explanation / Answer
#include <stdlib.h>
#include <stdio.h>
int main()
{
FILE *rfile,*vfile;
char Rfile[100];
char Vfile[100];
char output[100];
do{
printf("Enter name of file containing resistance values: ");
scanf("%s",Rfile);
rfile = fopen(Rfile,"rb");
if(!rfile)
printf("Wrong filename or file does not exist. Please enter again ");
else
break;
}while(1);
do{
printf("Enter name of file containing voltage drop values: ");
scanf("%s",Vfile);
vfile = fopen(Vfile,"rb");
if(!vfile)
printf("Wrong filename or file does not exist. Please enter again ");
else
break;
}while(1);
int size = 0;
double res[20];
double voltage[20];
double current[20];
double power[20];
double minres = 99999.99, maxres=0;
double minvol = 99.99, maxvol=-99.99;
double maxcur = maxvol/minres;
double mincur = -maxcur;
double maxpower = maxvol * maxcur;
double minpower = minvol * mincur;
double sumvol=0,sumcur=0,sumpow=0;
while( fread(&res[size],sizeof(double),1,rfile) && size<20)
{
if(!fread(&voltage[size],sizeof(double),1,vfile))
{
printf("Error occurred - VFile does not have corresponding value ");
return 0;
}
current[size] = voltage[size]/res[size];
power[size] = voltage[size] * current[size];
sumvol += voltage[size];
sumcur += current[size];
sumpow += power[size];
size++;
}
printf("Enter name of output file: ");
scanf("%s",output);
FILE *op = fopen(output,"w");
fprintf(op," R (ohms) V (volts) ");
int i;
for(i=0;i<size;i++)
{
fprintf(op,"RV pair %3d: %8.2lf %8.2lf ",i,res[i],voltage[i]);
if( voltage[i] > maxvol )
maxvol = voltage[i];
if( voltage[i] < minvol )
minvol = voltage[i];
if( current[i] > maxcur)
maxcur = current[i];
if( current[i] < mincur)
mincur = current[i];
if( power[i] > maxpower)
maxpower = power[i];
if( power[i] < minpower)
minpower = power[i];
}
fprintf(op," ");
fprintf(op," Voltage Current Power ");
fprintf(op,"MIN %8.2lf %8.4lf %8.4lf ",minvol,mincur,minpower);
fprintf(op,"MAX %8.2lf %8.4lf %8.4lf ",maxvol,maxcur,maxpower);
fprintf(op,"AVG %8.2lf %8.4lf %8.4lf ",sumvol/size,sumcur/size,sumpow/size);
return 0;
}