# What does the colon in Tikz coordinates mean?

``````\draw (0,0) -- (60:.75cm) arc (60:180:.75cm);
``````

What does the colon in `(60:.75cm)` mean? Normally, I'd define a normal point there.

• Figured it out and wrote a neat answer, but apparently I can't post it within 8 h of asking, it told me AFTER letting me write the answer!! (this is a bug report) Commented Mar 7, 2012 at 20:32
• That's hilarious, the same second!
– Werner
Commented Mar 7, 2012 at 20:37
• @Werner Well, that's a first. Commented Mar 7, 2012 at 20:38

The colon signifies that polar coordinates are being used. `(60:.75cm)` means the point that is at an angle of 60° and a distance of 0.75cm from the origin.

In the TikZ/PGF manual this is mentioned in section 13.2 Coordinate Systems, p 125:

The implicit form for `canvas polar` coordinates is the following: you specify the angle and the distance, separated by a colon as in `(30:1cm)`.

This also holds for other coordinate systems like `xyz polar`. Alternatively, if you're not interested in this shorthand notation, TikZ also provides

``````\pgfpointpolar{<degree>}{<x-radius>/<y-radius>}
``````

where `<y-radius>` is optional. See section 70 Specifying Coordinates (p 571) of the documentation.

• "If the optional `y-radius` is given, the polar coordinate is actually a coordinate on an ellipse whose `x-radius` is given by `x-radius` and whose `y-radius` is given by `y-radius`." Commented May 26, 2022 at 8:22