方位角:
αAB:
ΔxAB=xB-xA=-207.8<0, ΔyAB=yB-yA=88.17>0, αAB在第四象限
αAB=360°+arc tan[(xB-xA)/(yB-yA)]=360°+arc tan[-207.86/88.17]=292°59'8"
αBC:
ΔxBC=xC-xB=-133.09<0, ΔyBC=yC-yB=453.47>0, αBC在第四象限
αBC=360°-arc tan(ΔxBC/ΔyBC)=343°38'36"
αCD:
ΔxCD=xD-xC=194.97>0, ΔyCD=yD-yC=207.05>0, αCD在第一象限
αCD=arc tan(ΔxCD/ΔyCD)=43°16'44"
观测转角:
∠BOA=αB-αA=arc tan(xB/yB)-arc tan(xA/yA) = -3°41'14"
∠COB=αC-αB=arc tan(xC/yC)-arc tan(xB/yB) = -9°29'36"
∠DOC=αD-αC=arc tan(xD/yD)-arc tan(xC/yC)= -42'32"
追问再说观测角怎么是负数呢?
追答负数说明是逆时针转角
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