A vector refers to a quantity with both magnitude and direction. A vector should have three elements: starting point, length and direction. If the temperature of the retractable red thin wire in the thermometer is positive or negative, it is only a number under a certain unit of measurement (called a temperature scale) and there is no direction at all. The quantity that can be expressed by points on the number axis is called quantity.
Definition of vector:
In mathematics, there are both magnitude and direction, and the quantity that follows the parallelogram law is called vector.
There are directions and sizes, which are divided into free vectors and fixed vectors.
In mathematics, a quantity with only a size and no direction is called a quantity, and in physics it is called a scalar. Such as distance, mass, density, temperature, etc.
Note: The vector in linear algebra (real number space/complex number space) refers to the ordered array of n real numbers/complex numbers, which is called n-dimensional vector. α=(a 1, a2, …, an) is called an n-dimensional vector. Where ai is called the i-th component of vector α.
("1" of "a 1" is the subscript of A, "I" of "ai" is the subscript of A, and so on).
In programming languages, vectors also exist. A vector has a starting point and a direction. Usually represented by line segments with arrows.