科学计算科学计算 (23).pdf
AnnotationsAxes appearanceRetain plot when adding new plotsDivide the figure4 4.2 2 FormattingFormatting andand AnnotationAnnotation1 1AnnotationsAnnotationstitlexlabelylabeltextlegend(1)The title Function Basic Syntaxtitle(txt)x=-2*pi:0.05:2*pi;y=sin(x);plot(x,y)title(y=sin(x)title(MATLAB,y=sin(x)1 1AnnotationsAnnotationsExample 1 Plot sine over-2，2,and add a title to the plot.title(y=cosomegat)title(y=eaxt)title(X_1geqX_2)title(bfy=cosomegat+beta)Font ModifierDescriptionbfBold fontitItalic fontrmNormal font1 1AnnotationsAnnotations(1)The title Function TeX MarkupMATLAB supports a subset of TeX markup.Use TeX markup to add superscripts and subscripts,modify the font type and color,and include special characters in the text.Color Text color title(y=cosomegat,Color,r)title(y=cosomegat,FontSize,24)FontSize Title font size1 1AnnotationsAnnotations(1)The title Function Using name-value pair argumentstitle(txt,Name,Value)x=-2*pi:0.05:2*pi;y=sin(x);plot(x,y)title(y=sin(x)xlabel(-2pi leq x leq 2pi)1 1AnnotationsAnnotations(2)The xlabel and ylabel Functionxlabel(txt)ylabel(txt)Plot the sine curve over-2,2,and label the x-axis.text(-2*pi,0,-2pi)text(3,0.28,leftarrow sin(x)1 1AnnotationsAnnotations(3)The text Functiontext(x,y,txt)Add a text description to the previous plot.x=linspace(0,2*pi,100);plot(x,sin(x);sin(2*x);sin(3*x)legend(sin(x),sin(2x),sin(3x)1 1AnnotationsAnnotations(4)The legend Functionlegend(label1,label2,.)Example 2 Plot sine curves with different frequencies and create a legend with descriptive labels for each plotted data series.2 2Axes AppearanceAxes Appearanceaxisgridbox axis(-pi,pi,-4,4)(1)axisBasic syntaxaxis(xmin,xmax,ymin,ymax,zmin,zmax )2 2Axes AppearanceAxes Appearance2 2Axes AppearanceAxes Appearance(2)axisOther axis style and modeaxis equal：Use the same length for the data units along each axis.axis square：Use axis lines with equal lengths.Adjust the increments between data units accordingly.axis auto：Automatically choose all axis limits.axis off：Hide axes lines and background axis on：Display axes lines and background x=0,1,1,0,0;y=0,0,1,1,0;plot(x,y)axis(-0.1,1.1,-0.1,1.1)axis equal;2 2Axes AppearanceAxes Appearancegrid ongrid offgrid2 2Axes AppearanceAxes Appearance(2)Display or hide axes grid linesbox onbox offboxDisplay or hide axes outlinex=linspace(0,2*pi,100);y=sin(x);sin(2*x);sin(0.5*x);plot(x,y)axis(0 7-1.2,1.2)title(不同频率正弦函数曲线不同频率正弦函数曲线);xlabel(Variable X);ylabel(Variable Y);text(2.5,sin(2.5),sin(x);text(1.5,sin(2*1.5),sin(2x);text(5.5,sin(0.5*5.5),sin(0.5x);legend(sin(x),sin(2x),sin(0.5x)grid onExample 3 Plot sinx、sin(2x)、sin(x/2),and add annotations to the plot.3 3Retain plot when adding new plotsRetain plot when adding new plotshold onhold offholdt=linspace(0,2*pi,100);x=sin(t);y=cos(t);plot(x,y,b)hold on;plot(2*x,2*y,r-)grid onaxis(-2.2 2.2-2.2 2.2)axis equalExample 4 Use hold on commamd to plot two concentric circles.subplot：the plot created in an axes.Syntaxsubplot(m,n,p)Arguments m and n specify the figure divided into an m-by-n grid.Argument p specifiesthat the p-th subplot is active plot zone.4 4Divide the figureDivide the figure subplot(2,2,1);x=linspace(0,2*pi,60);y=sin(x);plot(x,y);title(sin(x);axis(0,2*pi,-1,1);x=linspace(0,2*pi,60);subplot(2,2,1)plot(x,sin(x)-1);title(sin(x)-1);axis(0,2*pi,-2,0)subplot(2,1,2)plot(x,cos(x)+1);title(cos(x)+1);axis(0,2*pi,0,2)subplot(4,4,3)plot(x,tan(x);title(tan(x);axis(0,2*pi,-40,40)subplot(4,4,8)plot(x,cot(x);title(cot(x);axis(0,2*pi,-35,35)4 4Divide the figureDivide the figure
