万能方位角计算公式.doc

先计算出坐标增量：dX=Xb-XadY=Yb-YadY=dY+1E-10 为了使除数不为零而加一个很小的数方位角计算万能公式：Az=pi * (1-Sgn(dY)/2)-Atn(dX / dY) 单位为弧度 Az=Az * 180 /pi 单位为度此公式计算无需判断象限，只需在值小于0时加上360即可！其中，sgn()为求符号函数，若dX0时为1，dX=0时为0。使用此公式不用判断所在象限，直接将坐标增量代入即可求出方位角值，在用计算器编程时若没有SGN()函数可自行判断并用一个变量代替!VBA代码：方位角计算函数 Azimuth()Sx为起点X，Sy为起点YEx为终点X，Ey为终点YStyle指明返回值格式Style=-1为弧度格式Style=0为“DD MM SS”格式Style=1为“DD-MM-SS”格式Style=2为“DDMMSS”格式Style=其它值时返回十进制度值Function Azimuth(Sx As Double, Sy As Double, Ex As Double, Ey As Double, Style As Integer)Dim DltX As Double, DltY As Double, A_tmp As Double, Pi As DoublePi = Atn(1) * 4 定义PI值DltX = Ex - SxDltY = Ey - Sy + 1E-20A_tmp = Pi * (1 - Sgn(DltY) / 2) - Atn(DltX / DltY) 计算方位角A_tmp = A_tmp * 180 / Pi 转换为360进制角度Azimuth = Deg2DMS(A_tmp, Style)End Function转换角度为度分秒Style=-1为弧度格式Style=0为“DD MM SS”格式Style=1为“DD-MM-SS”格式Style=2为“DDMMSS”格式Style=其它值时返回十进制度值Function Deg2DMS(DegValue As Double, Style As Integer)Dim tD As Integer, tM As Integer, Ts As Double, tmp As DoubletD = Int(DegValue)tmp = (DegValue - tD) * 60tM = Int(tmp)tmp = (tmp - tM) * 60Ts = Round(tmp, 1)select Case StyleCase -1 返回弧度Deg2DMS = DegValue * Atn(1) * 4 / 180Case 0Deg2DMS = tD & & Format(tM, 00) & & Format(Ts, 00.0)Case 1Deg2DMS = tD & - & Format(tM, 00) & - & Format(Ts, 00.0)Case 2Deg2DMS = tD & & Format(tM, 00) & & Format(Ts, 00.0) & Case ElseDeg2DMS = DegValueEnd SelectEnd FunctionFunction pol(AX As Double, AY As Double, Bx As Double, By As Double) As Stringpol = Azimuth(AX, AY, Bx, By, 2) & & Distance(AX, AY, Bx, By, 3)End FunctionFunction rec(alpha As String, dist As Double) As StringDim Alpha_Rad As DoubleAlpha_Rad = StringToRad(alpha)rec = dx: & Round(Cos(Alpha_Rad) * dist, 3) & dy: & Round(Sin(Alpha_Rad) * dist, 3)End FunctionFunction StringToRad(strAz) 将字符串格式方位角转换成弧度格式Dim azSubStrIf strAz ThenazSubStr =Split(strAz, -)If UBound(azSubStr) = 2 ThenStringToRad = (azSubStr(0) + azSubStr(1) / 60 + az