I've just started learning C, and I'm currently trying to create a program to automate a fishing minigame I made for my D&D campaign. In order to do so, I created a CSV containing all the tables I had originally written up. I've been trying a variety of things for about a week now to just simply read the CSV into C so that I can call specific elements at will. I've finally gotten something to very nearly work, but I'm getting a strange problem. Firstly, the CSV is formatted as such:
bluefish,str,2,5
bluefish,str,2,5
bluefish,str,2,5
bluefish,str,2,5
kahawai,dex,2,1000
narrow barred mackerel,str,3,5
It goes on for another 400 lines, but you get the point. My current code looks like the following:
typedef struct{
char name[50];
char contest[5];
int modifier;
int value;
} fts_t;
/*Checking for the file and opening it*/
FILE *tpointer;
tpointer = fopen("fishing_tables.csv", "r");
printf("Accessing Fishing Tables...\n");
if(tpointer == NULL){
printf("Error: Missing fishing_tables.csv");
return 0;
} else{
printf("Success! Importing Data...\n");
}
/*Creating a struct array and initializing variables*/
fts_t ft[400];
char buffer[1024];
int count = 0;
char name[100];
char contest[3];
int modifier;
int value;
while(fgets(buffer, 1024, tpointer)){
sscanf(buffer, " %[^,],%[^,],%d,%d", name, contest, &modifier, &value);
strcpy(ft[count].name, name);
strcpy(ft[count].contest, contest);
ft[count].modifier = modifier;
ft[count].value = value;
printf("%s\t%s\t%d\t%d\n", ft[count].name, ft[count].contest, ft[count].modifier, ft[count].value);
count++;
}
So, following above, I'm having it print out the elements of the struct at each count as it loops, just to check that it's creating the struct correctly. The problem comes in that the output looks like this:
dex 2 15
dex 2 15
dex 2 15
dex 2 15
dex 2 15
next 0 0 0
next 0 0 0
next 0 0 0
next 0 0 0
next 0 0 0
Now, hilariously, the rows beginning with "next" are the only rows printing correctly. I have these added in for some extra shenanigans in the context of the minigame, but what's important is that those are correct. However, in every other row, the name variable is not being read, and I'm really lost as to why, when the "next" rows are functioning fine. I've checked the actual variable itself, and it appears there's some sort of problem in my sscanf statement.
Any help is appreciated.
Related
I am kind of new to c programming but I want to create a c function that can read contents of a text file line by line separated by the tab delimiter(\t) and store them into a data structure, then after clear the file but have still failed. My code is
struct Busy_list{
int client_socket;
char JOB[1024];
int characters;
int No_jobs;
int IsReplace;
int Priority;
};
char** PriorityEvaluator(int client_socket){
struct Busy_list Array;
FILE *Ufptr;
Ufptr = fopen("Unsorted_busy_list.txt","r+");
for(int i;!EOF;i++){
fscanf(Ufptr, "%d\t%s\t%d\t%d\t%d\n",&Array.client_socket,&Array.JOB,&Array.characters,&Array.No_jobs,&Array.IsReplace);
}
fclose(Ufptr);
}
My Unsorted_busy_list file contains
/*
4 double fish 4 1 0
5 double praise 6 2 0
5 replace peter 2-o,4-o 5 2 1
*/
Try to replace your for loop with a while loop like this:
while((fscanf(Ufptr, "%d\t%s\t%d\t%d\t%d\n",&Arguments...)) != EOF){
}
I'm a beginner at C programming and I would appreciate some help in order to understand the problem.
Alright so, I have a data file (input.dat) with data like this: (first line) 0 2 3 4 5; (second line) 1 2 3 5 4, (third line and so on...). I'm required to read the data one line at a time until the end of file and print it. This is what I have done so far:
int main(void)
{
float coeffs[5];
FILE *input; /* File pointer to the input file */
fopen_s(&input, "input.dat", "r"); /* Location of the input file */
int count = 0;
/* Loops to read data set*/
while (fscanf_s(input, "%f %f %f %f %f ", &coeffs[0], &coeffs[1], &coeffs[2], &coeffs[3], &coeffs[4]) != EOF)
{
printf("a=%.4f; b=%.4f; c=%.4f; d=%.4f; e=%.4f\n", coeffs[0], coeffs[1], coeffs[2], coeffs[3], coeffs[4]);
count++;
}
return 0;
}
This is showing all of the lines in the data file at once. But this is not what I want. I need to read one line at a time and perform some calculations and conditions for that one line first before I move to the next line. So how can I do that?
Next problem is, for the first line, I need to implement a loop from -10 to +10 with increment of 2 (to get 11 results in total). For example the program will read the first line, display it on the screen, then for the first value -10, the program will calculate and again display something . Then it will do the same for -8, then for -6 and so on until +10. After the 11 results are displayed, the program will then and ONLY then, move to the second line and so on. Hence for each line in the data file, the program will have 11 results. How can I use the loop function with increment of 2 to achieve these 11 results?
I would appreciate if anyone can provide me a simple layout of the structure of the codes which I've to write. NOTE: The formats are a bit different than other compilers as I must use Microsoft Visual Studio to do it.
Add your calculations to your while loop. You are reading one line at a time anyway.
If you want to loop from -10 to 10 with increments of 2, use a for loop.
for(count = -10; count <= 10; count = count + 2)
{
// Calculations
}
In my class today we were assigned a project that involves reading in a file using the ./a.out"<"filename command. The contents of the file look like this
16915 46.25 32 32
10492 34.05 56 52
10027 98.53 94 44
13926 32.94 19 65
15736 87.67 5 1
16429 31.00 58 25
15123 49.93 65 38
19802 37.89 10 20
-1
but larger
My issue is that any scanf used afterwards is completely ignored and just scans in what looks like garbage when printed out, rather than taking in user input. In my actual program this is causing an issue with a menu that requires input.
How do I get the program to stop reading the file provided by the ./a.out"<"filename command?
also I stop searching at -1 rather than EOF for the sake of not having an extra set of array data starting with -1
ex
-1 0 0 0
in my real program the class size is a constant that is adjustable and is used to calculate class averages, I'd rather not have a set of 0's skewing that data.
#include <stdio.h>
int main(void)
{
int i = 0,j = 1,d,euid[200],num;
int tester = 0;
float hw[200],ex1[200],ex2[200];
while(j)
{
scanf("%d",&tester);
if( tester == -1)
{
j = 0;
}
else
{
euid[i] = tester;
}
scanf("%f",hw+i);
scanf("%f",ex1+i);
scanf("%f",ex2+i);
i++;
}
for(d = 0;d < 50;d++) /*50 because the actual file size contains much more than example*/
{
printf("euid = %d\n",euid[d]);
printf("hw = %f\n",hw[d]);
printf("ex1 = %f\n",ex1[d]);
printf("ex2 = %f\n",ex2[d]);
}
printf("input something user\n");
scanf("%d",&num);
printf("This is what is being printed out -> %d\n",num);
return 0;
}
I'm having the exact same problem. Tried every method I could find to eat the remaining input in the buffer, but it never ends.
Got it to work using fopen and fscanf, but the prof. said he prefers the code using a.out < filename
Turns out this is in fact not possible.
Hello I have file with text:
14
5 4
45 854
14
4
47 5
I need to write a text to a specific line. For example to the line number 4 (Doesn't matter whether I will append the text or rewrite the whole line):
14
5 4
45 854
14 new_text
4
47 5
I have found function fseek(). But in the documentation is written
fseek(file pointer,offset, position);
"Offset specifies the number of positions (bytes) to be moved from the location specified bt the position."
But I do not know the number of bites. I only know the number of lines. How to do that? Thank you
You can't do that, (text) files are not line-addressable.
Also, you can't insert data in the middle of a file.
The best way is to "spool" to a new file, i.e. read the input line by line, and write that to a new file which is the output. You can then easily keep track of which line you're on, and do whatever you want.
I will assume that you are going to be doing this many times for a single file, as such you would be better indexing the position of each newline char, for example you could use a function like this:
long *LinePosFind(int FileDes)
{
long * LinePosArr = malloc(500 * sizeof(long));
char TmpChar;
long LinesRead = 0;
long CharsRead = 0;
while(1 == read(FileDes, &TmpChar, 1))
{
if (!(LinesRead % 500)
{
LinePosArr = realloc(LinePosArr, (LinesRead + 500) * sizeof(long));
}
if (TmpChar == '\n')
{
LinePosArr[LinesRead++] = CharsRead;
}
CharsRead++;
}
return LinePosArr;
}
Then you can save the index of all the newlines for repeated use.
After this you can use it like so:
long *LineIndex = LinePosFind(FileDes);
long FourthLine = LineIndex[3];
Note I have not checked this code, just written from my head so it may need fixes, also, you should add some error checking for the malloc and read and realloc if you are using the code in production.
A text file holds information about a softball team. Each line has data arranged as follows:
4 Jessie Joybat 5 2 1 1
The first item is the player's number, conveniently in the range 0–18. The second item is the player's first name, and the third is the player's last name. Each name is a single word. The next item is the player's official times at bat, followed by the number of hits, walks, and runs batted in (RBIs). The file may contain data for more than one game, so the same player may have more than one line of data, and there may be data for other players between those lines. Write a program that stores the data into an array of structures. The structure should have members to represent the first and last names, the at bats, hits, walks, and RBIs (runs batted in), and the batting average (to be calculated later). You can use the player number as an array index. The program should read to end-of-file, and it should keep cumulative totals for each player.
The world of baseball statistics is an involved one. For example, a walk or reaching base on an error doesn't count as an at-bat but could possibly produce an RBI. But all this program has to do is read and process the data file, as described next, without worrying about how realistic the data is.
The simplest way for the program to proceed is to initialize the structure contents to zeros, read the file data into temporary variables, and then add them to the contents of the corresponding structure. After the program has finished reading the file, it should then calculate the batting average for each player and store it in the corresponding structure member. The batting average is calculated by dividing the cumulative number of hits for a player by the cumulative number of at-bats; it should be a floating-point calculation. The program should then display the cumulative data for each player along with a line showing the combined statistics for the entire team.
team.txt (text file I'm working with):
4 Jessie Joybat 5 2 1 1
4 Jessie Joybat 7 3 5 3
7 Jack Donner 6 3 1 2
11 Martin Garder 4 3 2 1
15 Jaime Curtis 7 4 1 2
2 Curtis Michel 3 2 2 3
9 Gillan Morthim 9 6 6 7
12 Brett Tyler 8 7 4 3
8 Hans Gunner 7 7 2 3
14 Jessie James 11 2 3 4
12 Brett Tyler 4 3 1 3
Since I'm a beginner in C, either I misinterpreted the task from what was asked originally or it's unfairly complex (I believe the former is the case). I'm so lost that I can't think of the way how could I fill in by the criteria of index (player number) every piece of data, keep track of whether he has more than one game, calculate and fetch bat average and then print.
What I have so far is:
#define LGT 30
struct profile {
int pl_num;
char name[LGT];
char lname[LGT];
int atbat[LGT/3];
int hits[LGT/3];
int walks[LGT/3];
int runs[LGT/3];
float batavg;
};
//It's wrong obviously but it's a starting point
int main(void)
{
FILE *flx;
int i,jc,flow=0;
struct profile stat[LGT]={{0}};
if((flx=fopen("team.txt","r"))==NULL) {
fprintf(stderr,"Can't read file team!\n");
exit(1);
}
for( jc = 0; jc < 11; jc++) {
fscanf(flx,"%d",&i);
stat[i].pl_num=i;
fscanf(flx,"%s",&stat[i].name);
fscanf(flx,"%s",&stat[i].lname);
fscanf(flx,"%d",&stat[i].atbat[flow]);
fscanf(flx,"%d",&stat[i].hits[flow]);
fscanf(flx,"%d",&stat[i].walks[flow]);
fscanf(flx,"%d",&stat[i].runs[flow]);
flow++;
}
}
Advice 1: don't declare arrays like atbat[LGT/3].
Advice 2: Instead of multiple fscanf you could read the whole line in a shot.
Advice 3: Since the number of players is limited and the player number has a good range (0-18), using that player number as an index into the struct array is a good idea.
Advice 4: Since you need cumulative data for each player (no need to store his history points), then you don't need arrays of integers, just an integer to represent the total.
So:
#include <stdio.h>
#define PLAYERS_NO 19
typedef struct
{
char name[20+1];
char lastName[25+1];
int atbat;
int hits;
int walks;
int runs;
float batavg;
} Profile;
int main(int argc, char** argv)
{
Profile stats[PLAYERS_NO];
int i;
FILE* dataFile;
int playerNo;
Profile tmpProfile;
int games = 0;
for(i=0; i<PLAYERS_NO; ++i)
{
stats[i].name[0] = '\0';
stats[i].lastName[0] = '\0';
stats[i].atbat = 0;
stats[i].hits = 0;
stats[i].walks = 0;
stats[i].runs = 0;
}
dataFile = fopen("team.txt", "r");
if ( dataFile == NULL )
{
fprintf(stderr, "Can't read file team!\n");
exit(1);
}
for(i=0; i<PLAYERS_NO && !feof(dataFile); ++i, ++games)
{
fscanf(dataFile, "%d", &playerNo);
if ( playerNo <0 || playerNo > PLAYERS_NO )
{
fprintf(stderr, "Player number out of range\n");
continue;
}
fscanf(dataFile, "%s %s %d %d %d %d",
&tmpProfile.name,
&tmpProfile.lastName,
&tmpProfile.atbat,
&tmpProfile.hits,
&tmpProfile.walks,
&tmpProfile.runs);
printf("READ: %d %s %s %d %d %d %d\n",
playerNo,
tmpProfile.name,
tmpProfile.lastName,
tmpProfile.atbat,
tmpProfile.hits,
tmpProfile.walks,
tmpProfile.runs);
strcpy(stats[playerNo].name, tmpProfile.name);
strcpy(stats[playerNo].lastName, tmpProfile.lastName);
stats[playerNo].atbat += tmpProfile.atbat;
stats[playerNo].hits += tmpProfile.hits;
stats[playerNo].walks += tmpProfile.walks;
stats[playerNo].runs += tmpProfile.runs;
}
/* exercise: compute the average */
fclose(dataFile);
for(i=0; i<PLAYERS_NO; ++i)
{
if ( stats[i].name[0] == '\0' )
continue;
printf("%d %s %s %d %d %d %d\n",
i,
stats[i].name,
stats[i].lastName,
stats[i].atbat,
stats[i].hits,
stats[i].walks,
stats[i].runs);
}
return 0;
}
The first rule of programming: Divide and conquer.
So you need to identify individual operations. One such operation is "load one row of input", another is "look up a player". If you have some of those operations (more will come up as you go), you can start building your program:
while( more_input ) {
row = load_one_row()
player = find_player( row.name )
if( !player ) {
player = create_player( row.name )
add_player( player )
}
... do something with row and player ...
}
when you have that, you can start to write all the functions.
An important point here is to write test cases. Start with a simple input and test the code to read a row. Do you get the correct results?
If so, test the code to find/create players.
The test cases make sure that you can forget about code that already works.
Use a framework like Check for this.
If I were doing this, I'd start with a structure that only held one "set" of data, then create an array of those structs:
struct profile {
char name[NAMELEN];
char lname[NAMELEN];
int atbat;
int hits;
int walks;
int runs;
float batavg;
};
Since you're using the player's number as the index into an array, you don't need to store it into the structure too.
I think that will simplify the problem a little bit. You don't need to store multiple data items for a single player -- when you get a duplicate, you just ignore some of the new data (like the names, which should be identical) and sum up the others (e.g., at-bats, hits).