Adding elements to an array within a for loop - c

Question

I would like to fill an array by looping through an for loop.
Let's say I have:
int8 myArray[30] = {0}; // Declaring and initializing an array which contains maximum 30 elements
Adding elements to an array within a for loop:
for (i = 0; i<5; i++)
{
myArray[0+(i*5)] = getNumberfromFunction1();
myArray[1+(i*5)] = getNumberfromFunction2();
myArray[2+(i*5)] = getNumberfromFunction3();
myArray[3+(i*5)] = getNumberfromFunction4();
myArray[4+(i*5)] = getNumberfromFunction5();
myArray[5+(i*5)] = getNumberfromFunction6();
}
Each Element of the loop shall be filled like:
myArray[0] = getNumberfromFunction1();
myArray[1] = getNumberFromFunction2();
...
...
myArray[5] = getNumberFromFunction6();
myArray[6] = getNumberFromFunction1();
....
....
The first turn with i=0 I, the index is correct:
myArray[0] = ..
myArray[1] = ..
..
..
myArray[5] = ..
The problem starts when i = 1:
Than I will have instead of myArray[6], myArray[5].
The first index in the foor loop will be always overwritten by the last index of the foor loop.
Any suggestions how to handle this?

Answer 1

In each run of your for loop, your are adding six values to the array! Thus, on each subsequent run, your should increment the "offset" count by i*6 (not i*5, as you have done):
for (i = 0; i<5; i++)
{
myArray[0+(i*6)] = getNumberfromFunction1();
myArray[1+(i*6)] = getNumberfromFunction2();
myArray[2+(i*6)] = getNumberfromFunction3();
myArray[3+(i*6)] = getNumberfromFunction4();
myArray[4+(i*6)] = getNumberfromFunction5();
myArray[5+(i*6)] = getNumberfromFunction6();
}
Try this.

Answer 2

You could multiply i by 6 instead of 5.

Answer 3

You are simulating a two-dimensional array on the top of a single dimensional array in C (However, both are laid out contiguously in memory).
You can achieve the same thing by having a two-dimensional array like this:
int array[5][6];
for (row = 0; row < 5; row++) {
for (col = 0; col < 6; col++)
array[row][col] = myFunc();
}
Or if you want to do it in your way, then you need to update your number from 5 to 6 as you are trying to have an array with 5 rows and 6 columns. See this answer to know how multi-dimensional arrays formatted in memory.
for (i = 0; i < 5; i++) {
myArray[0+(i*6)] = getNumberfromFunction1();
myArray[1+(i*6)] = getNumberfromFunction2();
myArray[2+(i*6)] = getNumberfromFunction3();
myArray[3+(i*6)] = getNumberfromFunction4();
myArray[4+(i*6)] = getNumberfromFunction5();
myArray[5+(i*6)] = getNumberfromFunction6();
}