xarrows

draw a set of arrows

Calling Sequence

xarrows(nx,ny,[arsize,style])

Arguments

:nx,ny real vectors or matrices of same size. : :arsize real scalar, size of the arrow head. The default value can

be obtained by setting arsize to -1.

: :style matrix or scalar. If style is a positive scalar it gives

the color to use for all arrows. If it is a negative scalar then the current color is used. If it is a vector style(i) gives the color to use for arrow i.

:

Description

xarrows draws a set of arrows given by nx and ny. If nx and ny are vectors, the ith arrow is defined by (nx(i),ny(i))–>(nx(i+1),ny(i+1)). If nx and ny are matrices:

nx=[xi_1 x1_2 ...; xf_1 xf_2 ...]
ny=[yi_1 y1_2 ...; yf_1 yf_2 ...]

the k th arrow is defined by (xi_k,yi_k)–>(xf_k,yf_k).

xarrows uses the current graphics scale which can be set by calling a high level drawing function such as plot2d.

Sample

Examples

x=2*%pi*(0:9)/8;
x1=[`sin`_(x); 9*`sin`_(x)];
y1=[`cos`_(x); 9*`cos`_(x)];
`plot2d`_([-10,10], [-10,10], [-1,-1], "022")
`xset`_("clipgrf")
xarrows(x1, y1, 1, 1:10)
`xset`_("clipoff")