The grad is a measurement of plane angles of value 1/400 of a full circle, thus dividing a right angle in 100. The unit is also known as the grade or gradian or (not to be confused with the word gradient which has a different meaning) or gon. One grad is equal to 9/10 of a degree or π/200 of a radian. This article is about angles in geometry. ... Jump to: navigation, search In Euclidean geometry, a circle is the set of all points at a fixed distance, called the radius, from a fixed point, called the centre (center). ... This article is about angles in geometry. ... In the above two images, the scalar field is in black and white, black representing higher values, and its corresponding gradient is represented by blue arrows. ... A degree (in full, a degree of arc), usually symbolized °, is a measurement of plane angle, representing 1／360 of a full rotation. ... Jump to: navigation, search Lower-case pi The mathematical constant Ï€ is the ratio of a circles circumference (Greek περιφέρεια, periphery) to its diameter and is commonly used in mathematics, physics, and engineering. ... See Radian (band) for the Austrian trio. ...

One advantage of this unit of measurement is that if one is travelling on a course of 117 grad (clockwise from due North), say, then the direction to one's left is instantly convertible into 17 grads, while that to one's right is at 217 grads and that behind one is at 317 grads. A disadvantage is that the extremely common angles of 30° and 60° must be expressed in fractions (33 1/3 grad and 66 2/3 grad respectively).

The unit originated in France as the grade, as part of the all metric system. Due to confusion with existing grad(e) units of northern Europe, the name gon was adopted in those regions. In German, the unit was formerly known as the Neugrad (new degree) now as the gon. The International System of Units (symbol: SI) (for the French phrase Syst me International dUnit s) is the most widely used system of units. ...

Although attempts at a general introduction was made, the unit was really only adopted in some countries and for specialized areas, like land measurement. The French artillery has used the grad for decades. The familiar degree, 1/360 of a circle, or the mathematically convenient radian, 1/(2π) of a circle, (used in the SI system of units) are generally used instead of the grad. In the '70s and '80s most scientific calculators offered the grad as well as radians and degrees for their trigonometric functions, but in recent years some offer degrees and radians only. See Radian (band) for the Austrian trio. ... Jump to: navigation, search The International System of Units (abbreviated SI from the French language name Système International dUnités) is the most widely used system of units. ... A basic arithmetic calculator. ... In mathematics, the trigonometric functions are functions of an angle, important when studying triangles and modeling periodic phenomena. ...

The symbol for the grad varies including "g", "gr", "grd and more latterly "gon". It is sometimes written as a superscript g, similarly to a degree sign: 50^g = 45°.

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