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https://creativecommons.org/licenses/by-sa/4.0CC BY-SA 4.0 Creative Commons Attribution-Share Alike 4.0 truetrue

Maxima CAS source code

/*

Batch file for Maxima CAS
save as a o.mac
run maxima : 
 maxima
and then : 


batch("gradient.mac");

*/
kill(all);
remvalue(all);



/* functions */





/* 
 point of the unit circle D={w:abs(w)=1 } where w=l(t) 
 t is angle in turns 
 1 turn = 360 degree = 2*Pi radians 
*/
give_unit_circle_point(t):= float(rectform(%e^(%i*t*2*%pi)))$

/* circle points */
give_circle_point(center, Radius, t) := center + Radius*give_unit_circle_point(t)$






/* 
vector cfrom c1 to c2 

from draw package : 
vector([x, y], [dx,dy]) 
plots vector [dx, dy] with origin in [x, y]. 

*/
give_vector(c1, c2):=block(
	[x,y,dx,dy],
	
	x: realpart(c1),
	y: imagpart(c1),
	dx : realpart(c2) - x,
	dy : imagpart(c2) - y,
	vector([x, y], [dx,dy])


)$


/* 

circle (Center, Radius )
n points c on the above circle 


*/
give_vectors(Center, Radius, n):=(
	[vv, v,dt, t, c],
	vv:[],
	dt : 1/n,
	t : 0,
	
	while (t <= 1) do (
		c : give_circle_point(Center, Radius,t),
		v : give_vector(Center, c),
		vv: cons(v,vv),
		t : t + dt		
	
	
	
	),
		
	vv




)$

/*
 compile( all); 
 
 */
 



Radius: 3$ /* radius of the circel around center */
n: 10;
Center: 0.5$


vv : give_vectors(Center, Radius, n);


 
path:""$ /*  if empty then file is in a home dir , path should end with "/" */ 
load(draw)$

draw2d(	
	terminal      = svg,
	file_name = sconcat(path, "vectors"),
	
	title = "vectors",
	/*xrange      = [-5,5],
       	yrange      = [5,5],
          */   
        line_width = 2, 
        line_type = solid,
        head_angle = 10, /* the angle, in degrees, between the arrow heads and the segment. Default value: 45 */

  
        head_both = false,
        head_type = filled,
        key = "",
        color = blue,     
        head_length = 1,
	             
	vv            
)$