1. A method of securely storing data in a nonvolatile memory array comprising: transforming a portion of data according to a first transformation to obtain first transformed data; storing the first transformed data in a first portion of the memory array; transforming the portion of data according to a second transformation to obtain second transformed data; and storing the second transformed data in a second portion of the memory array while the first transformed data is stored in the first portion of the memory array, to provide redundant storage of the portion of data.