real axis

American  

[ree-uhl ak-sis, reel] / ˈri əl ˈæk sɪs, ril /

noun

Mathematics.

1. the horizontal axis in an Argand diagram.

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Etymology

Origin of real axis

First recorded in 1830–35

Example Sentences

“There will be a little bit of moisture from that, and the real axis is split between the Northwest, Southern California and parts of Baja California.”

From Los Angeles Times

What if the set doesn’t come in one convenient piece like the interval between 0 and 1 and it’s a collection of points scattered randomly about the real axis?

From Scientific American

Complex here doesn’t mean complicated but refers to the complex plane, a two-dimensional plane with a real axis and an imaginary axis, where complex numbers like 2+3i live.

From Scientific American

The axis Ox is often called the real axis, and the axis Oy the imaginary axis.

From Project Gutenberg

It can now be easily proved that as z describes the real axis in its plane the point ζ describes once a circle of radius unity, with centre at ζ = 0, and that there is a definite correspondence of point to point between points in the z-plane which are above the real axis and points of the ζ-plane which are interior to this circle; in particular z = i corresponds to ζ = 0.

From Project Gutenberg