How can I take the average of only certain rows and columns of a 2D array?
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I have to take the average of only the test grades and put them into the last column but I have no idea how to do it. I have the function for the 2D array that takes in a filename that contains the grades but the first column is the student id so I don't need to take the average of that.
This is the code I have for the 2D array function.
#define x 10
#define y 6
void getData(float arr1[x][y])
FILE* graFile;
float arr2[x][y];
char userIn[50];
printf("Enter the text filename: ");
scanf("%s", userIn);
graFile = fopen(userIn, "r");
int studentId, test1, test2, test3, test4;
for(int i = 0; i < x; i++)
if(graFile != NULL)
fscanf(graFile, "%d%d%d%d%d", &studentId, &test1, &test2, &test3, &test4);
arr2[i][0] = studentId;
arr2[i][1] = test1;
arr2[i][2] = test2;
arr2[i][3] = test3;
arr2[i][4] = test4;
else
printf("nThis file does not exist.");
return;
printf("n %11s%11s%11s%11s%11s%11s", "Student Id","Test 1","Test 2","Test 3","Test 4","Finaln");
printf("*********************************************************************n");
for(int i = 0; i < x; i++)
for(int j = 0; j < y; j++)
printf("%11.0f", arr2[i][j]);
printf("n");
printf("*********************************************************************n");
fclose(graFile);
return;
That gives me this output
Enter the text filename: grades.txt
Student Id Test 1 Test 2 Test 3 Test 4 Final
*********************************************************************
6814 85 86 92 88 0
7234 76 81 84 78 0
6465 87 54 68 72 0
7899 92 90 88 86 0
9901 45 78 79 80 0
8234 77 87 84 98 0
7934 76 91 84 65 0
7284 56 81 87 98 0
7654 76 87 84 88 0
3534 86 81 84 73 0
*********************************************************************
Now I just need to create a new function that averages the test grades from this array and put it into the last column but I'm having trouble doing that. I appreciate any help I can get.
c arrays function average
asked Nov 11 at 2:47
Angie
12
add a comment |
up vote
0
down vote
favorite
I have to take the average of only the test grades and put them into the last column but I have no idea how to do it. I have the function for the 2D array that takes in a filename that contains the grades but the first column is the student id so I don't need to take the average of that.
This is the code I have for the 2D array function.
#define x 10
#define y 6
void getData(float arr1[x][y])
FILE* graFile;
float arr2[x][y];
char userIn[50];
printf("Enter the text filename: ");
scanf("%s", userIn);
graFile = fopen(userIn, "r");
int studentId, test1, test2, test3, test4;
for(int i = 0; i < x; i++)
if(graFile != NULL)
fscanf(graFile, "%d%d%d%d%d", &studentId, &test1, &test2, &test3, &test4);
arr2[i][0] = studentId;
arr2[i][1] = test1;
arr2[i][2] = test2;
arr2[i][3] = test3;
arr2[i][4] = test4;
else
printf("nThis file does not exist.");
return;
printf("n %11s%11s%11s%11s%11s%11s", "Student Id","Test 1","Test 2","Test 3","Test 4","Finaln");
printf("*********************************************************************n");
for(int i = 0; i < x; i++)
for(int j = 0; j < y; j++)
printf("%11.0f", arr2[i][j]);
printf("n");
printf("*********************************************************************n");
fclose(graFile);
return;
That gives me this output
Enter the text filename: grades.txt
Student Id Test 1 Test 2 Test 3 Test 4 Final
*********************************************************************
6814 85 86 92 88 0
7234 76 81 84 78 0
6465 87 54 68 72 0
7899 92 90 88 86 0
9901 45 78 79 80 0
8234 77 87 84 98 0
7934 76 91 84 65 0
7284 56 81 87 98 0
7654 76 87 84 88 0
3534 86 81 84 73 0
*********************************************************************
Now I just need to create a new function that averages the test grades from this array and put it into the last column but I'm having trouble doing that. I appreciate any help I can get.
c arrays function average
asked Nov 11 at 2:47
Angie
12
arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
Yes, exactly that.
– Angie
Nov 11 at 3:24
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
I have to take the average of only the test grades and put them into the last column but I have no idea how to do it. I have the function for the 2D array that takes in a filename that contains the grades but the first column is the student id so I don't need to take the average of that.
This is the code I have for the 2D array function.
#define x 10
#define y 6
void getData(float arr1[x][y])
FILE* graFile;
float arr2[x][y];
char userIn[50];
printf("Enter the text filename: ");
scanf("%s", userIn);
graFile = fopen(userIn, "r");
int studentId, test1, test2, test3, test4;
for(int i = 0; i < x; i++)
if(graFile != NULL)
fscanf(graFile, "%d%d%d%d%d", &studentId, &test1, &test2, &test3, &test4);
arr2[i][0] = studentId;
arr2[i][1] = test1;
arr2[i][2] = test2;
arr2[i][3] = test3;
arr2[i][4] = test4;
else
printf("nThis file does not exist.");
return;
printf("n %11s%11s%11s%11s%11s%11s", "Student Id","Test 1","Test 2","Test 3","Test 4","Finaln");
printf("*********************************************************************n");
for(int i = 0; i < x; i++)
for(int j = 0; j < y; j++)
printf("%11.0f", arr2[i][j]);
printf("n");
printf("*********************************************************************n");
fclose(graFile);
return;
That gives me this output
Enter the text filename: grades.txt
Student Id Test 1 Test 2 Test 3 Test 4 Final
*********************************************************************
6814 85 86 92 88 0
7234 76 81 84 78 0
6465 87 54 68 72 0
7899 92 90 88 86 0
9901 45 78 79 80 0
8234 77 87 84 98 0
7934 76 91 84 65 0
7284 56 81 87 98 0
7654 76 87 84 88 0
3534 86 81 84 73 0
*********************************************************************
Now I just need to create a new function that averages the test grades from this array and put it into the last column but I'm having trouble doing that. I appreciate any help I can get.
c arrays function average
asked Nov 11 at 2:47
Angie
12
I have to take the average of only the test grades and put them into the last column but I have no idea how to do it. I have the function for the 2D array that takes in a filename that contains the grades but the first column is the student id so I don't need to take the average of that.
This is the code I have for the 2D array function.
#define x 10
#define y 6
void getData(float arr1[x][y])
FILE* graFile;
float arr2[x][y];
char userIn[50];
printf("Enter the text filename: ");
scanf("%s", userIn);
graFile = fopen(userIn, "r");
int studentId, test1, test2, test3, test4;
for(int i = 0; i < x; i++)
if(graFile != NULL)
fscanf(graFile, "%d%d%d%d%d", &studentId, &test1, &test2, &test3, &test4);
arr2[i][0] = studentId;
arr2[i][1] = test1;
arr2[i][2] = test2;
arr2[i][3] = test3;
arr2[i][4] = test4;
else
printf("nThis file does not exist.");
return;
printf("n %11s%11s%11s%11s%11s%11s", "Student Id","Test 1","Test 2","Test 3","Test 4","Finaln");
printf("*********************************************************************n");
for(int i = 0; i < x; i++)
for(int j = 0; j < y; j++)
printf("%11.0f", arr2[i][j]);
printf("n");
printf("*********************************************************************n");
fclose(graFile);
return;
That gives me this output
Enter the text filename: grades.txt
Student Id Test 1 Test 2 Test 3 Test 4 Final
*********************************************************************
6814 85 86 92 88 0
7234 76 81 84 78 0
6465 87 54 68 72 0
7899 92 90 88 86 0
9901 45 78 79 80 0
8234 77 87 84 98 0
7934 76 91 84 65 0
7284 56 81 87 98 0
7654 76 87 84 88 0
3534 86 81 84 73 0
*********************************************************************
Now I just need to create a new function that averages the test grades from this array and put it into the last column but I'm having trouble doing that. I appreciate any help I can get.
c arrays function average
c arrays function average
asked Nov 11 at 2:47
Angie
12
asked Nov 11 at 2:47
Angie
12
asked Nov 11 at 2:47
Angie
12
asked Nov 11 at 2:47
Angie
12
asked Nov 11 at 2:47
Angie
12
12
arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
Yes, exactly that.
– Angie
Nov 11 at 3:24
add a comment |
arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
Yes, exactly that.
– Angie
Nov 11 at 3:24
arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
Yes, exactly that.
– Angie
Nov 11 at 3:24
Yes, exactly that.
– Angie
Nov 11 at 3:24
add a comment |
1 Answer
1
active
oldest
votes
up vote
0
down vote
void setAverage(float arr[y], int x)
for(int i = 0; i < x; i++)
arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4]) / 4;
answered Nov 11 at 3:47
rainhaven
1403
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
void setAverage(float arr[y], int x)
for(int i = 0; i < x; i++)
arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4]) / 4;
answered Nov 11 at 3:47
rainhaven
1403
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
add a comment |
up vote
0
down vote
void setAverage(float arr[y], int x)
for(int i = 0; i < x; i++)
arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4]) / 4;
answered Nov 11 at 3:47
rainhaven
1403
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
add a comment |
up vote
0
down vote
up vote
0
down vote
void setAverage(float arr[y], int x)
for(int i = 0; i < x; i++)
arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4]) / 4;
answered Nov 11 at 3:47
rainhaven
1403
void setAverage(float arr[y], int x)
for(int i = 0; i < x; i++)
arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4]) / 4;
answered Nov 11 at 3:47
rainhaven
1403
answered Nov 11 at 3:47
rainhaven
1403
answered Nov 11 at 3:47
rainhaven
1403
answered Nov 11 at 3:47
rainhaven
1403
1403
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
add a comment |
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
Thank you so much! Quick question though, where would I add my printf statement at?
– Angie
Nov 11 at 4:08
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
You can use printf as in your original code.
– rainhaven
Nov 11 at 4:38
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
While this might answer the authors question, it lacks some explaining words and/or links to documentation. Raw code snippets are not very helpful without some phrases around them. You may also find how to write a good answer very helpful. Please edit your answer.
– hellow
Nov 11 at 7:21
add a comment |
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arr2[i][5] = (test1 + test2 + test 3 + test4) / 4;
– rainhaven
Nov 11 at 3:04
Besides the obvious answer above, your program has several issues: 1. if(graFile != NULL) needs to be outside the for loop, not inside. 2. return value of fscanf needs to be checked; unless you're absolutely sure the file always contains at least x rows and the format is always consistent with your fscanf.
– rainhaven
Nov 11 at 3:07
Do you know how I could do that in a function of its own? The file only contains that amount of rows because this is a project for school so it will never be modified. So once I put the if condition outside the loop will my code be okay?
– Angie
Nov 11 at 3:11
A function take a float[x][y] as parameter, where the 1st column is student id, 2-5 columns are scores, the function saves the average to the last (6th) column. Is this you need?
– rainhaven
Nov 11 at 3:21
Yes, exactly that.
– Angie
Nov 11 at 3:24