坐标转换从经纬度坐标到大地坐标及源码.doc

坐标转换从经纬度坐标到大地坐标及源码利用网络上开源的资料,可以很容易的实现从经纬度坐标向各种投影坐标的转换,美国地质调查局开发USGS的GCTP就是很好的东西之一,有C语言版本的支持各种投影类型的源代码,比如UNIVERSALTRANSVERSEMERCATOR,ALBERSCONICALEQUALAREA,LAMBERTCONFORMALCONIC等等,我们机房使用的就是LAMBERTCONFORMALCONIC(LAMBERT圆锥等角投影), 和 ,可以轻松实现经纬度投影坐标和LAMBERTCONFORMALCONIC坐标的相互转化,其他投影方式使用的比较少,还要进一步研究,,比如长半轴,短半轴,中心点经纬度坐标,(r_maj,r_min,lat1,lat2,c_lon,c_lat,false_east,false_north)doubler_maj;                /*majoraxis*/doubler_min;                /*minoraxis*/doublelat1;                   /*firststandardparallel             */doublelat2;                   /*secondstandardparallel            */doublec_lon;                  /*centerlongitude                    */doublec_lat;                  /*centerlatitude                     */doublefalse_east;             /*xoffsetinmeters                  */doublefalse_north;            /*yoffsetinmeters                  */{doublesin_po;                 /*sinvalue                           */doublecos_po;                 /*cosvalue                           */doublecon;                    /*temporaryvariable                  */doublems1;                    /*smallm1                           */doublems2;                    /*smallm2                           */doubletemp;                   /*temporaryvariable                  */doublets0;                    /*smallt0