如何在Matlab极坐标polar绘图上增加刻度单位
一直以来，想在极坐标上面增加刻度，不知道该如何更改，经常是手动加入，费时费力。今天突然想起来为何不能通过修改Matlab的已知源代码，去更改呢？百度了之后，找到了以下的文章：
Site: http://blog.renren.com/share/240189843/2199786563
先不看文章，先来看Matlab默认绘制出来的效果图：
命令如下：
t = 0 : .01 : 2 * pi;
polar(t, sin(2 * t) .* cos(2 * t), '--r');
http://s6/mw690/001lQDg9gy71Lcp1Yxf45&690
那么问题来了，我想在0到360上面增加度的标记，即“°”，在0.1，0.2……上面增加微米标记，即μm。那么我们查找Maltab的代码。在命令窗口敲出polar，然后双击选中，右键选择打开该命令。
http://s15/mw690/001lQDg9gy71LcsiMcSce&690
打开后，找到第153（int2str(i*30)）和161(loc)行，即为我们想要增加的度的标示部分：
http://s13/mw690/001lQDg9gy71LcuT5Hm7c&690
更改为如下程序：
http://s4/mw690/001lQDg9gy71LcwVOq713&690
第二部分的修改，找到第136行：
http://s10/mw690/001lQDg9gy71LczUSHTa9&690
修改为：
http://s2/mw690/001lQDg9gy71LcC1ocx81&690
大功告成。注意，我们尽量不去修改Matlab原始的代码，所以我们这里将整个修改后的程序另存为：Mypolar.m。下面我们看一下修改后的绘图效果：
命令如下：
t = 0 : .01 : 2 * pi;
Mypolar(t, sin(2 * t) .* cos(2 * t), '--r');
http://s14/mw690/001lQDg9gy71LcE9wzX2d&690
同理，我们还可以用类似的方法修改相应代码，得到我们想要的效果。
最后，还是那句话：多看Matlab Help！多看Matlab
Help！多看Matlab
Help！
参考：
Site: http://blog.renren.com/share/240189843/2199786563
作者 : 黎芳芳
这两个命令的角度是定死的，没有提供任何接口去修改。
你一定要改，就只能改这两个命令的源代码了
http://s16/mw690/001lQDg9gy71LcGksBF4f&690
打开polar.m后可以找到下面这段语句
% plot spokes
th =
(1:6)*2*pi/12;
cst =
cos(th); snt = sin(th);
cs = [-cst;
cst];
sn = [-snt;
snt];
line(rmax*cs,rmax*sn,'linestyle',ls,'color',tc,'linewidth',1,...
'handlevisibility','off','parent',cax)
把th改成别的值就可以绘制不同的角度了，比如改成th
= (1:4)*2*pi/8;就是45度的分割线了。
当然下面还要继续改显示的度数
% annotate spokes in degrees
rt =
1.1*rmax;
for i =
1:length(th)
text(rt*cst(i),rt*snt(i),int2str(i*30),...
'horizontalalignment','center',...
'handlevisibility','off','parent',cax);
if i == length(th)
loc = int2str(0);
else
loc = int2str(180+i*30);
end
text(-rt*cst(i),-rt*snt(i),loc,'horizontalalignment','center',...
'handlevisibility','off','parent',cax)
end
把两个30全部改为45即可。
---------------------------------------------------------------------------------
t = 0:.01:2*pi;
polar(t,sin(2*t).*cos(2*t),'--r')
set(gca,'xdir','reverse')
次函数可简单的将x轴反向。。。
---------------------------------------------------------------------------------
基本上,
若是使用polar画图好像就无法更改其相关属性!
虽然可以使用set(gca,...)更改其相关属性,
但你会发现并没有更动! 原因为误认那些标示为'XTickLabel',
其实都不是,
切入polar.m看仔细就会发现其为text产生,
所以外部更改都无效!
我试了直接更改polar.m来实现即可
% draw radial circles
c82 = cos(82*pi/180);
s82 = sin(82*pi/180);
rinc = (rmax-rmin)/rticks;
ppp=(rmin+rinc):rinc:rmax; [color=red]ppp=fliplr(ppp);
iip=0;[/color]
for
i=(rmin+rinc):rinc:rmax
hhh =
plot(xunit*i,yunit*i,ls,'color',tc,'linewidth',1,...
'handlevisibility','off');[color=red] iip=iip+1;
[/color]
text((i+rinc/20)*c82,(i+rinc/20)*s82,
...
[' '
num2str([color=red]ppp(iip[/color][color=red])[/color])],'verticalalignment','bottom',...
'handlevisibility','off')
end
set(hhh,'linestyle','-') %
Make outer circle solid
------------------------
t=0:.01:2*pi; hh=polar77(20*t,200*sin(2*t).*cos(2*t),'--r');
-----------------------
此方法提供者应该是个高手，可惜我没有尝试成功
---------------------------------------------------------------------------------
官网上提供polarlabels.m
http://www.mathworks.com/matlabc
... ge/?term=polarlabel
http://www.chinavib.com/forum/viewthread.php?tid=74599&extra=&page=1
polarlabels([0:360]*pi/180,abs(sin([0:360]*pi/180))*10,'b',-90,10)
可实现一些简单的变化。。。似乎实现的功能不够强大
---------------------------------------------------------------------------------
有人提议polarhg.m
polarhg(theta,rho,'tdir','clockwise','rlim',[0 10], ...'rtick',[0 3
6 9],'tstep',45,'torig','up', 'color','m','linestyle',':')。这样整个图形就旋转了90度。
------------------
另外，polarhg还有个问题，当运行,比如，
>> theta =
0:pi/5:pi;
>> rho =
10*rand(size(theta));
>> h =
polarhg(theta,rho,'torig','down','color','m','linestyle',':');
??? Output argument "H" (and maybe others) not assigned during call
to "D:matlabworkpolarhg.m (polarhg)".
Error in ==> polarhg at 56
N = nargin;
-----------------------
解决问题:改第286行的num2str(Rmax-i)。
暂时没有下到polarhg.m文件。。。
——-----------------------------------------------------------------------------
个人推荐直接改polar.m文档，简单易实现。。。。
附：
修改后的Mypolar程序如下：
function hpol =
Mypolar(varargin)
%POLAR Polar
coordinate plot.
%
POLAR(THETA, RHO) makes a plot using polar coordinates
of
%
the angle THETA, in radians, versus the radius RHO.
%
POLAR(THETA, RHO, S) uses the linestyle specified in string
S.
%
See PLOT for a description of legal linestyles.
%
%
POLAR(AX, ...) plots into AX instead of GCA.
%
%
H = POLAR(...) returns a handle to the plotted object in
H.
%
%
Example:
%
t = 0 : .01 : 2 * pi;
%
polar(t, sin(2 * t) .* cos(2 * t), '--r');
%
%
See also PLOT, LOGLOG, SEMILOGX, SEMILOGY.
%
Copyright 1984-2010 The MathWorks, Inc.
%
$Revision: 5.22.4.11 $ $Date: 2011/03/09 06:59:01
$
% Parse possible Axes
input
[cax, args, nargs] = axescheck(varargin{:});
error(nargchk(1, 3, nargs, 'struct'));
if nargs < 1 || nargs
> 3
error('MATLAB:polar:InvalidInput',
'Requires 2 or 3 data
arguments.');
elseif
nargs ==
2
theta = args{1};
rho = args{2};
if ischar(rho)
line_style = rho;
rho = theta;
[mr, nr] = size(rho);
if
mr ==
1
theta = 1 : nr;
else
th = (1 : mr)';
theta = th(:, ones(1, nr));
end
else
line_style = 'auto';
end
elseif
nargs ==
1
theta = args{1};
line_style = 'auto';
rho = theta;
[mr, nr] = size(rho);
if mr == 1
theta = 1 : nr;
else
th = (1 : mr)';
theta = th(:, ones(1, nr));
end
else
% nargs ==
3
[theta, rho, line_style] = deal(args{1 : 3});
end
if ischar(theta) ||
ischar(rho)
error(message('MATLAB:polar:InvalidInputType'));
end
if ~isequal(size(theta),
size(rho))
error('MATLAB:polar:InvalidInput',
'THETA and RHO must be
the same size.');
end
% get hold
state
cax = newplot(cax);
next = lower(get(cax, 'NextPlot'));
hold_state = ishold(cax);
% get x-axis text
color so grid is in same color
tc = get(cax, 'XColor');
ls = get(cax, 'GridLineStyle');
% Hold on to current
Text defaults, reset them to the
% Axes' font
attributes so tick marks use them.
fAngle = get(cax, 'DefaultTextFontAngle');
fName = get(cax, 'DefaultTextFontName');
fSize = get(cax, 'DefaultTextFontSize');
fWeight = get(cax, 'DefaultTextFontWeight');
fUnits = get(cax, 'DefaultTextUnits');
set(cax, ...
'DefaultTextFontAngle',
get(cax, 'FontAngle'),
...
'DefaultTextFontName',
get(cax, 'FontName'),
...
'DefaultTextFontSize',
get(cax, 'FontSize'),
...
'DefaultTextFontWeight',
get(cax, 'FontWeight'),
...
'DefaultTextUnits',
'data');
% only do grids if
hold is off
if ~hold_state
% make a radial
grid
hold(cax, 'on');
% ensure that Inf
values don't enter into the limit calculation.
arho = abs(rho(:));
maxrho = max(arho(arho ~= Inf));
hhh = line([-maxrho, -maxrho, maxrho, maxrho], [-maxrho, maxrho,
maxrho, -maxrho], 'Parent', cax);
set(cax, 'DataAspectRatio',
[1, 1, 1], 'PlotBoxAspectRatioMode',
'auto');
v = [get(cax, 'XLim') get(cax,
'YLim')];
ticks = sum(get(cax, 'YTick') >=
0);
delete(hhh);
% check radial limits
and ticks
rmin = 0;
rmax = v(4);
rticks = max(ticks - 1, 2);
if rticks >
5 % see if we can reduce the
number
if rem(rticks, 2) ==
0
rticks = rticks / 2;
elseif
rem(rticks, 3) ==
0
rticks
= rticks / 3;
end
end
% define a
circle
th = 0 : pi / 50 : 2 * pi;
xunit = cos(th);
yunit = sin(th);
% now really force
points on x/y axes to lie on them exactly
inds = 1 : (length(th) - 1) / 4 : length(th);
xunit(inds(2 : 2 : 4)) = zeros(2, 1);
yunit(inds(1 : 2 : 5)) = zeros(3, 1);
% plot background if
necessary
if ~ischar(get(cax,
'Color'))
patch('XData', xunit *
rmax, 'YData', yunit *
rmax, ...
'EdgeColor', tc,
'FaceColor', get(cax,
'Color'),
...
'HandleVisibility',
'off', 'Parent', cax);
end
% draw radial
circles
c82 = cos(82 * pi / 180);
s82 = sin(82 * pi / 180);
rinc = (rmax - rmin) / rticks;
for
i = (rmin
+ rinc) : rinc : rmax
hhh = line(xunit * i, yunit * i, 'LineStyle', ls,
'Color', tc,
'LineWidth', 1,
...
'HandleVisibility',
'off', 'Parent', cax);
text((i + rinc / 20) * c82, (i + rinc / 20) * s82,
...
[' '
strcat(num2str(i),'mum')],
'VerticalAlignment',
'bottom', ...
'HandleVisibility',
'off', 'Parent', cax);
end
set(hhh, 'LineStyle', '-');
% Make outer circle
solid
% plot
spokes
th = (1 : 6) * 2 * pi / 12;
cst = cos(th);
snt = sin(th);
cs = [-cst; cst];
sn = [-snt; snt];
line(rmax * cs, rmax * sn, 'LineStyle', ls,
'Color', tc,
'LineWidth', 1,
...
'HandleVisibility',
'off', 'Parent', cax);
% annotate spokes in
degrees
rt = 1.1 * rmax;
for
i = 1 :
length(th)
text(rt * cst(i), rt * snt(i), strcat(int2str(i *
30),'circ'),...
'HorizontalAlignment',
'center', ...
'HandleVisibility',
'off', 'Parent', cax);
if i ==
length(th)
loc = int2str(0);
else
loc = int2str(180 + i * 30);
end
text(-rt * cst(i), -rt * snt(i), strcat(loc,'circ'),
'HorizontalAlignment',
'center', ...
'HandleVisibility',
'off', 'Parent', cax);
end
% set view to
2-D
view(cax, 2);
% set axis
limits
axis(cax, rmax * [-1, 1, -1.15, 1.15]);
end
% Reset
defaults.
set(cax, ...
'DefaultTextFontAngle',
fAngle , ...
'DefaultTextFontName',
fName , ...
'DefaultTextFontSize',
fSize, ...
'DefaultTextFontWeight',
fWeight, ...
'DefaultTextUnits',
fUnits );
% transform data to
Cartesian coordinates.
xx = rho .* cos(theta);
yy = rho .* sin(theta);
% plot data on top of
grid
if strcmp(line_style,
'auto')
q = plot(xx, yy, 'Parent', cax);
else
q = plot(xx, yy, line_style, 'Parent', cax);
end
if nargout ==
1
hpol = q;
end
if ~hold_state
set(cax,
'DataAspectRatio',
[1, 1, 1]), axis(cax, 'off');
set(cax, 'NextPlot', next);
end
set(get(cax, 'XLabel'),
'Visible',
'on');
set(get(cax, 'YLabel'),
'Visible',
'on');
if ~isempty(q)
&& ~isdeployed
makemcode('RegisterHandle',
cax, 'IgnoreHandle', q,
'FunctionName', 'polar');
end
end
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(2016-09-29 19:18:14)