Median of array values

[naim1]

Hi All,

If i have 8-bit values saved in an array of 127 bytes, how would i calculate the Median of this array. Median of a set of values would be the central value of the set when its values are arranged in ascending order.

Any help would be great.

-naim1

[Chris_F]

What part don't you understand?

Is this C++?

http://www.cplusplus.com/reference/algorithm/sort/

[naim1]

Thanks Chris F for the link.

Is it possible to do it using plain ANSI C ?

[Chris_F]

I've never used this before, but here is a C library function.

http://www.cplusplus.com/reference/c...cstdlib/qsort/

[naim1]

Thanks again Chris F.

any idea where can i get code for qsort()?

Another point is that the values are not constant in the array, instead the array is being filled up constatly by newer values which are bering received from the serial port. Is it possible to do the sorting operation of every new incoming value dynamically, something like serial-arithmatic?

[Paul McKenzie]

Thanks again Chris F.

any idea where can i get code for qsort()?

The qsort() is a standard library function. Any code for it would come with your compiler (if your compiler offers source code to the library routines).

Regards,

Paul McKenzie

[laserlight]

If you wanted a better average case performance than sorting and then picking the middle, you could use the nth element algorithm of picking a pivot, partitioning as in quick sort, and then only performing the recursion on the partition that contains the middle element.

Another point is that the values are not constant in the array, instead the array is being filled up constatly by newer values which are bering received from the serial port. Is it possible to do the sorting operation of every new incoming value dynamically, something like serial-arithmatic?

As in the new values replace existing ones in the array?