c. y¡¯=-xsinx/cosy£¬ y(2)=1
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dfdt??g??f?4? g £¬ ? ?£¨3£©Çó΢·Ö·½³Ì×é ? f f ? g µ±³õʼÌõ¼þΪ
dtdgf(0)=2£¬g(2)=5 ʱµÄ½â¡£
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ÓÃÃüÁî plot(x,y)»æÖƺ¯Êý y=cos(x)ÔÚÁ½¸öÖÜÆÚÄÚµÄͼÐΡ£ x=0:0.01:2*pi; y=cos(x); plot(x,y)
ÔÚͬһͼÐδ°¿ÚÖÐÓÃÃüÁî plot(x,y)»æ³öÕýÏÒÓàÏÒº¯ÊýµÄͼÐΡ£ x=0:0.01:2*pi; y=[sin(x);cos(x)]; plot(x,y)
ÓÃÃüÁîplot(Y)»æÖƾØÕó Y=[5 4 3 8 9 10£»3 4 4 5 8 2 £»8 12 13 21 18 25 £»9 8 8 9 6 7]µÄͼÐΡ£
Y=[5 4 3 8 9 10;3 4 4 5 8 2 ;8 12 13 21 18 25 ;9 8 8 9 6 7]; plot(Y) ÓÃplot(Z)»æÖÆͼÐΡ£ x=0:pi/20:2*pi; Z=sin(x)+cos(x)*i
plot(Z)
µÈ¼ÛÓÚplot(real(Z),imag(Z))
ÓÃplot(x1,y1,x2,y2,¡)ÔÚͬһ´°¿ÚÖлæÖƶàÌõÇúÏߣ¬ÇÒ×ø±êºÍ³¤¶È¶¼²»Í¬¡£
t1=0:0.1:3*pi; t2=0:0.1:6;
plot(t1,sin(t1),t2,sqrt(t2)) »æÖÆÕýÏÒº¯ÊýµÄ¶ÔÊý×ø±êÇúÏß¡£ t=0.1:0.1:3*pi; y=sin(t); figure(1) semilogx(t,y)
grid on %ΪͼÐδ°¿ÚÌí¼ÓÍø¸ñ figure(2) semilogy(t,y) figure(3) loglog(t,y)
Óà plotyy º¯Êý»æÖÆË« y ÖáͼÐΡ£ t1=0:0.1:3*pi; t2=0:0.1:6; y1=sin(t1); y2=sqrt(t2);
plotyy(t1,y1,t2,y2,'semilogx') grid on
ÔÚͬһͼÐδ°¿ÚÖÐÓò»Í¬µÄ»æͼº¯Êý»æÖÆͬһº¯ÊýÇúÏß y ? x µÄË« y ÖáͼÐΡ£ x=0:0.1:6; y=sqrt(x);
plotyy(x,y,x,y,¡¯semilogy¡¯,¡¯plot¡¯) Óò»Í¬µÄÏßÐͺͱê×¢À´»æÖÆÁ½ÌõÇúÏß¡£ t1=0:0.1:2*pi; t2=0:0.1:6; y1=sin(t1); y2=sqrt(t2);
plot(t1,y1,':hb',t2,y2,'--g')
Óà subplot º¯Êý°ÑÁ½ÖÖ²»Í¬µÄͼÐÎ×ÛºÏÔÚÒ»¸öͼÐδ°¿ÚÖС£ subplot(2,2,1) t=0.1:0.1:2*pi; y=sin(t); semilogx(t,y) grid on subplot(2,2,2) t=0:0.1:4*pi; y=sin(t);
plot(t,y) subplot(2,2,3) x=1:0.01:5; y=exp(x);
plotyy(x,y,x,y,¡¯semilogx¡¯,¡¯plot¡¯) subplot(2,2,4) x=1:0.1:10; y=sqrt(x); plot(x,y,¡¯:rd¡¯)
? xº¯Êý z ? e £¬¶¨ÒåÇøÓòΪ[-2£¬2]¡Á[-2£¬2]¡£Éú³ÉÍø¸ñ²¢
¼ÆËãÆäÍø¸ñµãÉϵĺ¯ÊýÖµ¡£
[X,Y] = meshgrid(-2:2:2, -2:2:2); [X,Y] %½«»®·Ö½á¹ûÊä³öÖÁ¾ØÕó ans =
-2 0 2 -2 -2 -2
-2 0 2 0 0 0 -2 0 2 2 2 2
Z = X .* exp(-X.^2 - Y.^2); %¼ÆËãÍø¸ñµãÉϵĺ¯ÊýÖµ¸³Óè±äÁ¿ Z Z =
?x2?y2