MATLAB一些函数实例.pdf

1.三角波产生器 t -3:0.01:3; f1 tripuls(t); subplot(3,1,1); plot(t,f1); axis([-3,3,-0.2,1.2]) set(gcf,color,w); f2 tripuls(t,4); subplot(3,1,2); plot(t,f2); axis([-3,3,-0.2,1.2]) %set(gcf,color,w); f3 tripuls(t,4,-1); subplot(3,1,3); plot(t,f3); axis([-3,3,-0.2,1.2]) 2.离散序列的相加与相乘 function [x,n] jxl (x1,x2,n1,n2) n min (min (n1),min (n2)):max (max (n1),max (n2)); s1 zeros(1,length (n));s2 s1; s1(find ((n min (n1))(n max (n1)) 1)) x1; s2 (find ((n min (n2))(n max (n2)) 1)) x2; x s1+s2;//x s1.*s2:%序列乘 axis([(min (min (n1),min (n2))-1),(max (max (n1),max (n2))+1),(min (x)-0.5), (max (x)+0.5)]) 3.序列的反摺 function [x,n] xlfz(x1,n1) x fliplr (x1);n fliplr (n1); stem (n,x,filled) axis([min (n)-1,max (n)+1,min (x)-0.5,max (x)+0.5]) 4.序列的卷积 function [x,n] gghconv (x1,x2,n1,n2) x conv (x1,x2) ns n1(1)+n2 (1); leg length (x1)+length (x2)-2; n ns:(ns+leg) subplot (2,2,1) stem (n1,x1,filled) title (x1(n)) xlabel (n) subplot (2,2,2) stem (n2,x2,filled) title (x2 (n)) xlabel (n) subplot (2,2,3) stem (n,x,filled) title (x (n) n1(n)+x2 (n)) xlabel (n) p get (gca,position); p (3) 2.4*p (3); set (gca,position,p) 5.l 连续函数的卷积 function [f,t] gggfconv (f1,f2,t1,t2) d input (ÇëÊäÈë²ÉÑù¼ä¸ôd:); f conv (f1,f2) f f*d; ts t1(1)+t2 (1); l length (f1)+length (f2)-2; t ts:d:(ts+l*d); subplot (2,2,1) plot (t1,f1) axis([min (t1),max (t1),min (f1)-min (f1)*0.2,max (f1)+max (f1)*0.2]) title (f1(t)) xlabel (t) subplot (2,2,2) plot (t2,f2) axis([min (t2),max (t2),min (f2)-min (f2)*0.2,max (f2)+max (f2)*0.2]) title (f2 (t)) xlabel (t) subplot (2,2,3) plot (t,f) axis([min (t),max (t),min (f)-min (f)*0.2,max (f)+max (f)*0.2]) p get (gca,position); p (3) 2.4*p (3); set (gca,position,p) title (f(t) f1(t)*f2 (t)) xlabel (t) 6.周期信号傅里叶级数 display (傅里叶展开的项数) m input (m ); t -2*pi:0.01:2*pi; n round (length (t)/4); f [ones(n,1);-1*ones(n,1);ones(n,1);-1*ones(n+1,1)]; ones(314,1); y zeros(m+1,max (size (t))); figure (1); y (m+1,:) f;