# Argand diagram

- a Cartesian coordinate system consisting of two perpendicular axes for graphing complex numbers, the real part of a number being plotted along the horizontal axis and the imaginary part along the vertical axis.

Compare imaginary axis, real axis.

## Origin of Argand diagram^{}

1905–10; named after Jean-Robert Argand (1768–1822), Swiss mathematician

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

# Argand diagram

- maths a diagram in which complex numbers are represented by the points in the plane the coordinates of which are respectively the real and imaginary parts of the number, so that the number x + i y is represented by the point (x, y), or by the corresponding vector < x, y >. If the polar coordinates of (x, y) are (r, θ), r is the modulus and θ the argument of x + i ySee also amplitude (def. 5)

## Word Origin

C19: named after Jean-Robert Argand (1768–1822), French mathematician

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012