From timhesterberg at gmail.com  Fri Oct  2 17:22:34 2009
From: timhesterberg at gmail.com (Tim Hesterberg)
Date: Fri, 2 Oct 2009 08:22:34 -0700
Subject: [Rd] suggest enhancement to segments and arrows to facilitate
	horizontal and vertical segments
Message-ID: <e21d304c0910020822r761cbaaeq2bee03abc21b5f6f@mail.gmail.com>

I suggest a simple enhancement to segments() and arrows() to
facilitate drawing horizontal and vertical segments --
set default values for the second x and y arguments equal to the first set.
This is handy, especially when the expressions for coordinates are long.

Compare:

Segments:
< function (x0, y0, x1 = x0, y1 = y0, col = par("fg"), lty = par("lty"),
---
> function (x0, y0, x1, y1, col = par("fg"), lty = par("lty"),

Arrows:
< function (x0, y0, x1 = x0, y1 = y0, length = 0.25, angle = 30, code = 2,
---
> function (x0, y0, x1, y1, length = 0.25, angle = 30, code = 2,

Tim Hesterberg



[Rd] suggest enhancement to segments and arrows to facilitate horizontal and vertical segments
Tim Hesterberg