How to access a four dimensional array?
 

Hello,

I have never used multidimensional array for a long time so please consider this as a newbie question. I am editing a program that uses a 4 dimensional array and I think I'm losing track of the indexes.

day = 0 to 30
hour = 0 to 23
channel = 0 to 7
len = 0 to 63

unsigned char idx[day][channel][hour][len];

I have seen that the assignment to a string is

snprintf(idx[day][hour][channel], 64, "%s/%s", dayofmonth, hourofday);

Is this correct?

Because when I access with a day argument, that day value goes into the hour part.

Regards,
archieval

That does not look like a "4-dimensional array". What I see is a simple structure with each entry having the four elements.

For the data ranges you show, a 4-D array would have 31*24*8*1 = 5952 discrete points.

Declaration and usage should be in the same order.

MT

Sorry, I changed len 0 to 63, now it's a four dimensional array?

Regards,
archieval

It should be like this?
snprintf(idx[day][channel][hour], 64, "%s/%s", dayofmonth, hourofday);

Yes, that's right.

To me, a "4-dimensional array" is a structure with 4 numerical indices, where a particular combination of indices produces a value (or another structure)

It seems like you want to use the ranges you specified as the data, and not as the array indices.

Try it in a proper language, where the compiler is HELPING you, instead of confusing you.

http://fruttenboel.verhoeven272.nl/mocka/index.html

Ah I see, ok now I get what you mean. Or perhaps a little bit. I am using the day, channel, and hour indices combination as a "single variable" to hold a string (the string is a file path that contains directory name that specifies the day, and the actual file that contains the channel number and hour number). So the purpose of that array is only to hold a string. So it's not really "4 dimensional", but rather a 3 dimensional array that holds a string. Thanks for the clarification.

Regards,
archieval

What is the purpose of this? I am using a specific cross compiler because I am working on embedded systems. I cannot add this module on my compiler.

Regards,
archieval