Guys n Gals,
I can't seem to find the routine for calculating the offset from a point to a line on the Hp-48, using TDS Pro.
I have a line defined by two coordinates, 1 & 2. Course between them is North 68 degrees, 22 minutes, 13 seconds, at a distance of 1000 feet.
I have the coordinates of another point, 3.
I want to find how far from point 1, on line 1 to 2, the perpendicular intersect is to point 3, and the distance from point 3 to the line 1 to 2.
I have done this several years ago, and it seems to me there was a "trick" to imputing the bearing in on a Bearing-Bearing intersect routine, or something.
thanx,
geezer:-)
Two ways come to mind although it's been some time since I used a 48/cogo card to do this.
One, if you have the option of doing a 'point to line' inverse. Put in the two points defining your line and the third you wish to see the station and offset and solve.
or
Two, do a bearing-bearing intersect. Define point one as your start point on the bearing one to two. Next point would be your third point, entering the bearing as point one to two and then either adding or subtracting 90 degrees from the bearing to get your perpendicular and solve for the intersect. Some quick inverses would give you the station and offset.
Hope that helps.
Just because I'm paranoid, doesn't mean they aren't out to get me.
thanx,
I can get the results I want if I first inverse between the two line points to get the bearing, (which in this case I have done; then I can add or subtract 90 degrees from that to get my bearing from point number 3.
What I am looking for is the key sequence to have the HP automatically calculate the 90 degree bearing for the intersect. In my cogo routine on my computer, to get that perpendicular bearing it would be "1..2+90" for the second bearing of the intersect.
But that apparently isn't the input for the HP.
thanx
gzr
Under the COGO Menu, select J for inverse between points
select softkey D for Byline
input point 3 for the inverse point
input point 1 for the beginning point of line
input for point 2 of line, or you can input the bearing of the line
It has a few different options for solving.
I have the TDS COGO card in an HP48GX
I hope this helps
sure sounds like it. I will give it a shot.
many thanx,.
gzr