= Digit-array integer representation
{title2=$\operatorname{val}(a)=\sum_{i=0}^{L-1}a_i b^i$}
Store an <integer> in a nonempty <array> of <numeral digits>, with the least significant digit first and a fixed <radix> $b\geq2$. Normalized digits satisfy $0\leq a_i<b$. High-order zeros do not change the value. Adding digit arrays coefficientwise or multiplying them by <discrete convolution> gives the correct value before normalization, because these operations add or multiply the corresponding powers of the radix. Exact temporary arithmetic, or a radix and accumulator size chosen to prevent <integer overflow>, is required.
Back to article page
