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Showing posts from January, 2013

Parity check

Parity check is use to check error of the data send. When data is send from source to receiver , data may lose or having error. The receiver will receive error data. There are 2 types of error: Single bit error- Only one bit is changed from 1 to 0 or from 0 to 1. Burst error- 2 or more bits in the data unit have changed. For the receiver to ensure the data send is correct , error detection is use. Error detection uses the concepts of redundancy, which means adding extra bits detecting error of the destination. Parity check is the simplest technique in error detection techniques. A redundant bit is appended (added at the end of the data) to every data unit.The parity also have 2 type which are odd parity and even parity. Even Parity is the total number of 1's in data plus parity bit must be an even number while the Old parity is odd number. Example of even parity: Data #1's in data Parity bit(P) # 1's (data + P) 0110110 4(even) 0 4(even) 0011111 5(od

Sort

Sorting is one of the most common applications in computer science. The process through which data are arranged in either ascending or descending order according to their values. Sorts are generally classified as either internal or external: Internal sort -All of data are held in primary storage during the sorting process. External sort- Uses primary storage for the data currently being sorted and secondary data for any data that will not fit in primary memory. In choosing Sorting techniques there are few  factors you should consider which are: Number of item and load Number of characters in item or record Average case  Best case Worst case Sorter stabilization especially for sorter that use 2 keys Sorting Method There are many sorting techniques, and every technique can be categorized according to their method group.Here is the method: Priority Queue Sorting Method An array A is divided into sub-array P represents priority queue and sub-array Q represents