# Efficiently finding the maximum value of a column in a matrix

Imagine I have a matrix of the following form:

TestArray = $((a_1,b_1,...),(a_2,b_2,...),(a_3,b_3,...),...)$, where a specific example might be:

TestArray = $((10^6,1,...),(10^7,7,...),(10^3,4,...))$

In the above example, we have $Max[a_i] = 10^7$, and $Max[b_i] = 7$.

In a single line of Mathematica, how can I find the maximum $a_i$, $b_i$, etc.? Moreover, what is the most computationally efficient manner in which to do this?

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