Question

C Programming

I am trying to also print the frequency and the occurrence of an input text file. I got the occurrence to but cant get the frequency.

Formula for frequency is "Occurrence / total input count", this is the percentage of occurrence.

Can someone please help me to get the frequency to work.

Code:

int freq[26] = {0};

fgets(input1, 10000, (FILE*)MyFile);

for(i=0; i< strlen(input); i++) {

freq[input[i]-'a']++;

count++;

}

printf("Text count = %d", count);

printf("\n");

printf("Frequency of plain text\n");

for(int i=0;i<26;i++){

char temp = 'a' + i;

printf("%c : %d : %f\n",temp,freq[i],(float)(freq[i]/count));

Results:

Text count = 868
Frequency of plain text
a : 64 : 0.000000
b : 11 : 0.000000
c : 37 : 0.000000
d : 31 : 0.000000
e : 109 : 0.000000
f : 15 : 0.000000
g : 13 : 0.000000
h : 30 : 0.000000
i : 68 : 0.000000
j : 2 : 0.000000
k : 6 : 0.000000
l : 37 : 0.000000
m : 18 : 0.000000
n : 61 : 0.000000
o : 56 : 0.000000
p : 21 : 0.000000
q : 3 : 0.000000
r : 54 : 0.000000
s : 64 : 0.000000
t : 77 : 0.000000
u : 44 : 0.000000
v : 12 : 0.000000
w : 11 : 0.000000
x : 1 : 0.000000
y : 22 : 0.000000
z : 1 : 0.000000

Answer 1

• Below is the detailed implementation of the above problem in C with code and output shown.
• For better understanding please read the comments mentioned in the code.
• The mistake in your code in printing the frequency is that the division is not resulting in floating number as the denominator have to be typecasted to float to make the integer division resulting in floating point number, you can see the code below for reference.
• You can print the occurence and frequency as shown in the code and also you can read ultiple lines from your text file from the code below.
• Note: keep the input file(input.txt) and the c file(.c) in the same directory so that the program can read the file.
• CODE:

//include headers
#include<stdio.h>
#include<string.h>

//driver function
int main(){
//file pointer
FILE *MyFile;
//create frequency array
int freq[26] = {0};
//open file in reading mode
MyFile = fopen("input.txt" , "r");
//create a character array of size 10000
char input[10000];
//count stores total input count of letters
int count=0;
//read till EOF(end-of-file)
while(!feof(MyFile)){
//input text
fgets(input, 10000, (FILE*)MyFile);
//iterate through string
for(int i=0; i< strlen(input); i++){
//increment count of alphabets read
if(input[i]<='z' && input[i]>='a')
freq[input[i]-'a']++;
//increment total count
count++;
}
}
//print total text count
printf("Text count = %d", count);
//newline
printf("\n");
//heading
printf("Frequency of plain text\n");
//for all characters from a to z
for(int i=0;i<26;i++){
//current character
char temp = 'a' + i;
//print it's occurrence and frequency
printf("%c : %d : %f\n",temp,freq[i],(freq[i]/(float)count));
}
return 0;
}

• INPUT/OUTPUT:

input file(input.txt)

abcdbdbdbdbdhasuhfsakdjajbfkdjgkjdngsithosietnsnskbsgbnsklgbnskbnslibnsbn
dnfbdsskjdfbsjbskjfbsjk

output

Text count = 97
Frequency of plain text
a : 4 : 0.041237
b : 16 : 0.164948
c : 1 : 0.010309
d : 11 : 0.113402
e : 1 : 0.010309
f : 5 : 0.051546
g : 4 : 0.041237
h : 3 : 0.030928
i : 3 : 0.030928
j : 8 : 0.082474
k : 9 : 0.092784
l : 2 : 0.020619
m : 0 : 0.000000
n : 9 : 0.092784
o : 1 : 0.010309
p : 0 : 0.000000
q : 0 : 0.000000
r : 0 : 0.000000
s : 16 : 0.164948
t : 2 : 0.020619
u : 1 : 0.010309
v : 0 : 0.000000
w : 0 : 0.000000
x : 0 : 0.000000
y : 0 : 0.000000
z : 0 : 0.000000

• Below are the screenshot attached for the code and input/output for better clarity and understanding.

CODE

INPUT/OUTPUT

input.txt

output

So if you still have any doubt regarding this solution please feel free to ask it in the comment section below and if it is helpful then please upvote this solution, THANK YOU.