MATLAB Lecture 8 School of Mathematical Sciences Xiamen University http://gdjpkc.xmu.edu.cn 2 Basic plotting Commands Plotting st The process of constructing a basic graph to meet your presentation graphics requirements is outlined in the following table. The table shows seven typical steps and some example code for each If you are performing analysis only, you may want to view various graphs just to explore your data. In this case, steps I and 3 may be all you need. If you are creating presentation graphics, you may want to fine-tune your graph by positioning it on the page, setting line styles and colors, adding annotations, and making other such Improvements I Typic 1. Prepare your data X=0:0.2:12 yl= bessel(l, x) 2. Select a window and position a plot figure(1) region within the window subplot(2, 2, 1) 3.Call elementary plotting function h=plot(x,yl, x,y2, x, y3); elect line and marker characteris- set(h Line Width, 2, 'Line Style"), ('",-,".) set(h, 'Color, f'r, g; b)) 5. Set axis limits, tick marks, and grid axis([0 12-0.]) grid 6. Annotate the graph with axis xlabel(Time,") labels. legend. and text ylabel('Amplitude legend(h, First, 'Second, Third) tle( Bessel Functions) yⅸx]=min(yl1) text(x(ix),y, First Min \ rightarrow Horizontalali 7. Export graph print-depsc-tiff-r200 myplot Plot plot(X, Y): plots vector Y versus vector X. If X or Y is a matrix, then the vector is plotted versus the rows or columns of the matrix, whichever line up It can be used to plot of a curve expressed in explicit scheme or parameter 123456};y=[1-1.52-3-17] Lec8-2MATLAB Lecture 8  School of Mathematical Sciences Xiamen University  http://gdjpkc.xmu.edu.cn  Lec8­2  ² Basic Plotting Commands  ¸ Plotting Steps  The process of constructing a basic graph to meet your presentation graphics  requirements is outlined in the following table. The table shows seven typical steps and  some example code for each.  If you are performing analysis only, you may want to view various graphs just to explore your data.  In this  case,  steps  1  and  3  may be all you need.  If you are creating  presentation graphics,  you may want  to fine­tune your graph by  positioning it on the page,  setting line styles  and colors,  adding annotations,  and making other such  improvements.  Step  Typical Code 1. Prepare your data  x = 0:0.2:12; y1 = bessel(1,x);  y2 = bessel(2,x);  y3 = bessel(3,x);  2. Select a window and position a plot  region within the window  figure(1) subplot(2,2,1) 3. Call elementary plotting function  h = plot(x,y1,x,y2,x,y3);  4. Select line and marker characteris￾tics  set(h,'LineWidth',2,{'LineStyle'},{'­­';':';'­.'})  set(h,{'Color'},{'r';'g';'b'})  5. Set axis limits, tick marks, and grid  lines  axis([0 12 ­0.5 1]) grid on  6.  Annotate the graph with axis labels, legend, and text  xlabel('Time') ylabel('Amplitude') legend(h,'First','Second','Third') title('Bessel Functions') [y,ix] = min(y1);  text(x(ix),y,'First Min \rightarrow',...  'HorizontalAlignment','right')  7. Export graph  print ­depsc ­tiff ­r200 myplot  ¸ Plot function  plot(X,Y): plots vector Y versus vector X. If X or Y is a matrix, then the vector is plotted  versus the rows or columns of the matrix, whichever line up.  It  can be used to  plot  of a curve expressed  in  explicit scheme or parameter representation.  >> x = [1 2 3 4 5 6]; y = [1 ­1.5 2 ­3 ­1 7];  >> plot(x, y);