which associates a definite value of the scalar quantity 
with each point specified by position vector 
(in short, a scalar valued function of ). [P3.1]
throughout: some region of space
is: a quantity which can be specified fully by a number and an appropriate unit at each point within that region. [P3.1]
therefore is: a field which associates a definite value of the scalar quantity with each point specified by position vector (in short, a scalar valued function of ). [P3.1]
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