To implement a programmatic solution (ie simulation) of a real life process- the obtaining, processing, and display of your status in the course.

In addition to the new skills required on previous projects, to successfully accomplish/perform this project, the listed resources/experiences need to be consulted/achieved:

• you can calculate percentages
• ability to open and access data from files
• using loops to automate a process
• using functions to organize your code

Throughout the semester, you've been accumulating points for your class participation, journal, and projects.

This information has been accessible via the status tool.

The task at hand can benefit from loop and array assistance.

For instance, taking the number input and processing it so each digit occupies its own array element would facilate your efforts in the overall task– a process strongly resembling some of the work you had to do in the mbe1 project to get your input ready for the multiply by 11 activity.

As indicated, this task shares many attributes with the mbe1 project; in fact, the mental math process itself may be slightly simpler. That affords us the opportunity to introduce and learn about further programming optimizations, without the concurrent burden of new concepts.

Specifically, we will look at modularizing aspects of our solution, using functions, to make for a cleaner, more organized codebase.

We've been using functions all along (everytime you use fprintf() or fscanf(), for instance), but the value is not just in using pre-existing ones, but also in making our own to use.

Like variables, functions need to be declared.

We can declare them at various scopes (file/global, block/local)… if you wish for the function to be accessible by all functions within a program, you will want to declare it with a global scope.

If a particular function is only to be used by a specific function, and no others, you can opt to declare it local scope (ie within the function that will be calling it).

A function is basically a module or subroutine. It is a mini-program, focusing on the performing of a particular process.

Like a program, it takes input, does processing, and provides output.

Unlike a program, its input may not come from the keyboard, but instead from particular variables, and may not send output to the screen, but instead channel output in a way that it can be stored into a variable.

This distinctions aside, a function can in many ways be viewed as a micro- or sub-program/routine. We use functions to assist us in making our code more readable/organized/navigable.

Keeping everything in ONE file, ONE big function in that one file, is rather monolithic. In time, with sufficiently large programs, such an arrangement would become a tad unwieldy. So functions help to keep our focus short yet attentive.

To create a function we must first declare (or prototype) it. This needs to happen BEFORE said function is ever used (just as with variables- you must declare a variable before it is first used, otherwise the compiler yells).

A function, in many ways, is like a programmable variable (or is a variable with programming attached).

As such, it has a return value of a type (the function's output), a name, and parameters (input).

We see this with main()… here are two variations of a main() function declaration (technically also the start of the definition as well, in the case of main()):

int main()

In this example, we see the declaration of main() where it has a return value of int, meaning, upon completion, main() will return a value corresponding with an int data type (also in main()'s case, being the first function run, we tend to return a status code to the operating system– 0 for success, non-zero for some sort of error or deferred success).

main(), in this case, takes no parameters (just an empty set of parenthesis)… due to this, we refer to this function as a parameterless function. A function without parameters. Without input.

Now: this is technically a different form of input and output than you are used to. Input doesn't ALWAYS have to come from the keyboard, nor does output ALWAYS have to go to the screen. Input instead is desired informating being acquired for the process at hand, and output is the byproduct of performing the operation. Sometimes this means keyboard input and screen output- but not always.

Additionally, with or without parameters, we can always perform additional input (and output) within a given function, through the use of various input and output methods (like fprintf()/fscanf()).

int main(int argc, char **argv)

In this case, our main() function actually takes parameters- two, in fact:

1. an integer, we are calling argc
2. a double pointer, we are calling argv

This function takes two parameters, two pieces of input, available to us in the form of variables, by those names, of those types. We make use of them as we need to in accomplishing the program at hand.

So, when we wish to create functions of our own, we need:

• the return type
• the function name
• 0 or more parameters, identifying their order and type

For example, let us make a sum() function. Here would be a likely prototype (we'd place it above main()):

int sum(int *, int);

A function prototype (vs. its definition) will have a terminating semi-colon, as you see above.

In our case, our sum() function has the following:

• a return type of int (particular variable name doesn't matter, type does)
• the function's name (sum)
• a comma-separated list of types corresponding to the parameters (again, variable names do not matter, but the type is important).

Our sum() function will take an integer array (denoted by the int pointer above), and a size (the second, regular int).

Now, parameter order very much matters. In our case, an “int *” came first, followed by an “int”… we need to be mindful of this order to successfully call and use the function.

To successfully complete this project, the following criteria must be met:

• Code must compile cleanly (no warnings or errors)
  • Use the -Wall flag when compiling.
• Output must be correct, and resemble the form given in the sample output above.
• Code must be nicely and consistently indented (you may use the indent tool)
• Code must utilize the algorithm presented above
• Code must be commented
  • have a properly filled-out comment banner at the top
  • have at least 20% of your program consist of //-style descriptive comments
• Track/version the source code in a repository
• Submit a copy of your source code to me using the submit tool.

To submit this program to me using the submit tool, run the following command at your lab46 prompt:

$ submit cprog gfo0 gfo0.c
Submitting cprog project "gfo0":
    -> gfo0.c(OK)

SUCCESSFULLY SUBMITTED

You should get some sort of confirmation indicating successful submission if all went according to plan. If not, check for typos and or locational mismatches.

Throughout the semester, your class-related activities have been numerically captured and made available to you via the status tool.

Now that we are at the end, and your programming skillset is significantly expanded, I would like you to write a program to take this data and calculate your grade (reflective of currently recorded data).

I've designed a tool that will take all your status data and 'flatten' it… converting all the necessary data into one stream of values. To obtain this data, simply run the flattenstatus command and the file status.flat will be created in your current working directory.

For example:

lab46:~/src/cprog/eoce/0x4$ flattenstatus
lab46:~/src/cprog/eoce/0x4$ cat status.flat
-1 0 1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 1 1 1 1 -2 1 1 1 0 1 0 1 0 1 0 0 1 -3 11 13 6 9 4 9 5 9 6 9 19 20 6 0 18 20 -4
lab46:~/src/cprog/eoce/0x4$ 

Your program needs to do the following:

• check for and open the status.flat file
  • if error occurs, display message and exit
• reading one integer at a time, load the values into an array according to their category
• there will be three categories (arrays), each one identified by a header/sentinel value:
  • -1 indicates the start of participation data (28% of grade)
  • -2 indicates end of participation data / start of journal data (36% of grade)
  • -3 indicates end of journal data / start of project data (36% of grade)
  • -4 indicates end of project data (and end of data stream)
• once loaded into their arrays, calculate the grade component
• tally up all three, and print out the results

Final program output should resemble the following:

lab46:~/src/cprog/eoce/0x4$ ./0x4
Participation Component: 20 / 28
Journal Component:       20 / 36
Projects Component:      30 / 36
Total:                   70 /100
lab46:~/src/cprog/eoce/0x4$