L1/Manhattan/Rectilinear Distance Metric is a distance metric (𝑑) defined as 𝑑(𝑢̅,𝑣̅) = 𝐿1 = ||𝑢̅-𝑣̅||1 = 𝛴1≤𝑖≤𝑛|𝑢̅𝑖-𝑣̅𝑖| where 𝑢̅,𝑣̅are vectors in ℝ𝑛 utilizes the L1 Norm function