★一个类型转换的问题?有点复杂
有一系列数据,如下形式:
16974890.40617606,4086725.47725926,1146
16973570.14449645,4086958.30351305,1147
16972883.72994449,4086837.05825281,1148
16971897.39350236,4088019.40261314,1149
16971364.31753635,4088172.62827098,1150
16970220.04424601,4087828.76652812,1151
16969684.77038935,4087356.05661786,1152
16966867.65026119,4088048.11198157,1153
16962907.69034056,4088796.67054906,1154
16962120.49998508,4088851.30164117,1155
我定义了一个结构体
typedef struct {
string xCor;
string yCor;
int index;
}dfxPoint;
我用一个string类型str_temp取出了第一列数据“16962120.49998508”
现在想将其四舍五入保留2位小数,写入到一个新字符串dfxP_tmp.xCor中,如下的语句却不能实现:
…………………………………………
float xx=atof(str_temp.c_str());
sprintf(dfxP_tmp.xCor,"%-10.2f", xx);
…………………………………………
请问这个问题应该如何解决?