# straightarrow: adds straight arrow between two points In diagram: Functions for Visualising Simple Graphs (Networks), Plotting Flow Diagrams

## Description

Plots straight line between two points

adds an arrowhead at a certain distance.

## Usage

 ```1 2 3``` ```straightarrow(from, to, lwd = 2, lty = 1, lcol = "black", arr.col = lcol, arr.pos = 0.5, endhead = FALSE, segment = c(0,1), ...) ```

## Arguments

 `from ` coordinates (x,y) of the point *from* which to draw arrow. `to ` coordinates (x,y) of the point *to* which to draw arrow. `lwd ` line width. `lty ` line type. `lcol ` line color. `arr.col ` arrow color. `arr.pos ` relative position of arrowhead. `endhead ` if `TRUE`: the arrow line stops at the arrowhead; default = `FALSE`. `segment ` if not `c(0,1)`: then the arrow line will cover only part of the requested path, e.g. if segment = c(0.2,0.8), it will start 0.2 from `from` and till 0.8. `... ` arguments passed to function Arrows.

## Details

a straight arrow is drawn between the points '(`from`, `to`)' The position of the arrowhead, is set with `arr.pos`, a value between 0(start point) and 1(endpoint)

The type of the arrowhead is set with `arr.type` which can take the values:

• "simple" : uses comparable R function arrows.

• "triangle": uses filled triangle.

• "curved" : draws arrowhead with curved edges.

• "circle" : draws circular head.

• "ellipse" : draws ellepsoid head

• "T" : draws T-shaped (blunt) head

see `Arrowhead` from package shape for details on arrow head.

## Value

coordinates (x,y) where arrowhead is drawn

## Author(s)

Karline Soetaert <[email protected]>

`bentarrow`, `segmentarrow`, `curvedarrow` `selfarrow`, `splitarrow`, `treearrow`,

`arrows`: the comparable R function,

`Arrows`: more complicated arrow function from package shape.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12``` ```openplotmat(main = "straightarrow") pos <- coordinates(c(2, 3, 1)) for (i in 1:5) straightarrow(from = pos[i, ], to = pos[i+1, ], arr.pos = 0.5) straightarrow(from = pos[6, ], to = pos[6, ] + c(0.3, 0.), arr.type = "T", arr.pos = 1, arr.lwd = 3) for (i in 1:6) textrect(pos[i, ], lab = LETTERS[i], radx = 0.05) ```

### Example output

```Loading required package: shape
```

diagram documentation built on May 31, 2017, 2:44 a.m.