double PA_X
double PA_Y
double PA_ANGLE

double PB_X
double PB_Y

double tmpAngle=atan2(PA_X-PB_X,PA_Y-PB_Y)-PA_ANGLE;//PAから見たPBの角度を求める
double tmpRange=sqrt((PA_X-PB_X)*(PA_X-PB_X)+(PA_Y-PB_Y)*(PA_Y-PB_Y));//距離を求める

RelativeX=cos(tmpAngle)*tmpRange;//角度と距離から座標を求める
RelativeY=sin(tmpAngle)*tmpRange;

Line 2: error: expected initializer before 'double'
compilation terminated due to -Wfatal-errors.