基于matlab的坐标正反算

测量程序设计实验报告
实验名称：坐标正反算
实验三坐标正反算
一、实验目的
编写坐标正反算程序，并对格式化文件数据进行计算，验证程序。

二、实验内容
1、编写坐标正算程序
1）建立以xy_direct命名的函数，函数输入输出格式为
[x2,y2] = xy_direct(x1,y1,distance, azimuth)
度转度分秒：
>> function dms= degree2dms(jiaodu)
>>degree = fix(jiaodu);
>>mimute = fix((jiaodu-degree)*60);
>>second = ((jiaodu-degree)*60-mimute)*60;
>>dms = degree+mimute/100+second/10000;
度分秒转度：
>> function degree = dms2degree(jiaodu)
>>degree = fix(jiaodu);
>> mimute = fix((jiaodu-degree)*100);
>>second = (jiaodu-degree-mimute/100)*10000;
>>degree = degree+mimute/60+second/3600;
弧度转度：
>> function dms=rad2dms(rad)
>> rad=abs(rad);
>> jiaodu=rad*180.0/pi;
>> % l=fix(a)
>> % b=(a-l)*60.0
>> % m=fix(b)
>> % a=l+m/100.0+(b-m)*0.006
>> % if(rad<0)
>> % dms=-a;
>> % else
>> % dms=a;
>> % end
>> degree = fix(jiaodu);
>> mimute = fix((jiaodu-degree)*60);
>> second = ((jiaodu-degree)*60-mimute)*60;
>> dms = degree+mimute/100+second/10000;
>> if(rad<0)
dms=-dms;
else
dms=dms;
end
return
>> function [x2,y2] = xy_direct(x1,y1,distance, azimuth)
>>x2=x1+distance.*cos(azimuth*pi/180);
>>y2=y1+distance.*sin(azimuth*pi/180);
>>end
2) 对文件data1.txt中数据进行坐标正算，并将已知点和计算点坐标按照格式存贮在文件data2.txt中，
data1.txt格式为： x1 y1 距离方位角（dd.mmss）
data2.txt格式为：
x1 y1 x2 y2
>> [filename,pathname]=uigetfile;
>> file=[pathname,filename];
>> data=importdata(file);
>> %[x1,y1]=data.data(:,[1,2]);
>> azimuth=dms2degree(data.data(:,4));
>> distance=data.data(:,3);
>> %[x2,y2]=xy_direct(x1,y1,distance,azimuth);
>>[x2,y2]=xy_direct(data.data(:,1),data.data(:,2),distance,azimuth); >> [filename_out,pathname_out]=uiputfile;
>> fileout=[pathname_out,filename_out];
>> fid=fopen(fileout,'wt');
>> fprintf(fid,'x1 y1 x2 y2\n');
>> fprintf(fid,'%8.2f %8.2f %8.2f %8.2f\n',[data.data(:,1:2),x2,y2]); >> fclose('all')
ans =
2、编写坐标反算程序
1）建立以xy_inv命名的函数，函数输入输出格式为
[distance, azimuth] = xy_inv(x1,y1, x2,y2)
>> function [distance, azimuth] = xy_inv(x1,y1, x2,y2)
>> delt_x=x2-x1;
>> delt_y=y2-y1;
>> [m,x]=size(delt_x);
>> azimuth=zeros(0,m);
>> for i=1:m
azimuth_temp=atan2(abs(delt_y(i)),abs(delt_x(i)));
if delt_x(i)>0&&delt_y(i)>0
azimuth(i)=azimuth_temp;
elseif delt_x(i)>0&&delt_y(i)<0
azimuth(i)=2*pi-azimuth_temp;
elseif delt_x(i)<0&&delt_y(i)>0
azimuth(i)=pi-azimuth_temp;
else delt_x(i)<0&&delt_y(i)<0;
azimuth(i)=pi+azimuth_temp;
end
end
>> azimuth=rad2dms(azimuth)
>> distance=sqrt((x2-x1).^2+(y2-y1).^2);
>> %fprintf('两点间距离：%8.3f ；方位角为：%8.3f',distance,azimuth);
2) 对文件data2.txt中数据进行坐标反算，并将计算结果按照格式存贮在文件data3.txt中，
Data3.txt格式为： x1 y1 x2 y2 距离方位角（dd.mmss）
>> [filename,pathname] = uigetfile;
>>file = [pathname, filename];
>>data=importdata(file);
>> [distance, azimuth] =
xy_inv(data.data(:,1),data.data(:,2),data.data(:,3),data.data(:,4)); >> [filename_out,pathname_out] = uiputfile;
>>fileout = [pathname_out, filename_out];
>>fid = fopen(fileout,'wt');
>>fprintf(fid,' x1 y1 x2 y2 距离方位角（dd.mmss）\n'); >>fprintf(fid,'%8.2f %8.2f %8.2f %8.2f %8.2f %8.4f\n',[dat a.data(:,1:4),distance,azimuth']');
>>fclose('all');
3、可能用到的函数
开根号，sqrt(x)
sin(rad)、cos(rad)、atan2(y,x)，find。