Create

There are two ways to create a new point group:  you can use this command or you can use the CGEditor.  Previous C&G users may prefer to use this command but the CGEditor allows the user the ability to view and edit the point group as it is being created.

If a coordinate file is not open, you will be prompted to open one using a file dialog.

Once the coordinate file is open, the point group file dialog can be used to specify the name of the point group file you wish to create.
 
Subgroup description <Enter when done>: Enter the subgroup description.
Specify points for subgroup <filename>:
[Block/Code/Desc/Elev/Indiv/liMits/Radius/Vertical_curve] <pick polyline>:
 Use any of the available methods, including picking a polyline in the drawing, to specify the point IDs of the points in the subgroup.  Remember that, within a given subgroup, you are defining a specific shape or line and thus the points need to be entered as an ordered sequence that properly defines the lot, alignment, etc.
Repeat the steps outlined above until all subgroups and their points have been entered.
To end the command and create the point group file, press Enter twice after specifying the last point in the last subgroup.

Using a Polyline to specify a group of points

If you pick a polyline, the coordinate file is searched for points having northings and eastings that match the x and y coordinates of the vertices of the polyline.  If none of the points in the coordinate file match the polyline vertices, then no points are added to the points in the current subgroup.  Any points that match are added to the subgroup points and you are prompted for the next point in the subgroup.  You may continue using any of the methods of specifying points, including picking other polylines.

Entering a Curve
First type "I" and enter to enter individual points.  As you are specifying the individual points in the subgroup you can specify a curve by entering the radius point ID immediately after entering the ID of the PC.  The radius point must be indicated by preceding its point ID with a plus sign for a clockwise curve or a minus sign for a counterclockwise curve.  The next point ID you enter is assumed to be the PT.

Vertical Curves

If you are creating a point group to define a road alignment, you may wish to enter vertical curve information so that both the horizontal and vertical alignments are defined. 

Note: You may find it more convenient to use the CGEditor to enter vertical curve information.

To do this type "V" and Enter at the command prompt.  You will see the following prompt:

Vertical Curve 1
[Next/slope-In/slope-Out/Length/pvi-Station/pvi-Elevation]:

For the first vertical curve you must enter five curve components.  Enter these five components by typing the capitalized letter representing the component that you wish to specify, then press Enter.  You will be prompted to enter the component specified.  

You must enter a value for each of the following five required fields:
The slope-In
slope-Out
Length of the vertical curve
pvi-Station
pvi-Elevation.

Entering succeeding vertical curves

After entering the information for the first vertical curve, enter <N> for Next.  Since the slope in and PVI elevation are determined by the previous vertical curve information, so you need only specify three fields for any additional curves:
slope-Out
Length
pvi-Station

Use Previous and Next to enter and/or change the vertical curve information. You may enter as many as fifty vertical curves.  You can press the F2 key at any time to view the prompt history screen, then use the scroll bar on the right to view the entire data entry sequence.

Multiple Subgroups

To place more than one subgroup in a single point group, press Enter when asked to select another point for the current subgroup.  This ends input for the current subgroup.
At the Subgroup description <Enter when done>: prompt, enter the name of the next subgroup and go on to enter a new series of points, including both horizontal and vertical curve information as needed.  
Continue to enter subgroups of points by repeating these steps until all subgroups have been entered.
When you have entered all the subgroups, press Enter until you get the Subgroup Description prompt. 
Press Enter at the Subgroup Description prompt to end the command and create the point group file.

Prompts

Subgroup description <Enter when done>: Enter the subgroup description.
Specify points for subgroup <filename>:
[Block/Code/Desc/Elev/Indiv/liMits/Radius/Vertical_curve] <pick polyline>: use one or more of the available methods to specify points in the current subgroup.
Vertical Curve 1
[Next/slope-In/slope-Out/Length/pvi-Station/pvi-Elevation]: specify which element of the vertical curve you wish to enter or type "N" and Enter to begin entering the next vertical curve.
Vertical Curve ##
[Next/slope-Out/Length/pvi-Station]: after entering the data for the first vertical curve the following curves are controlled by the initial curve.  Thus the prompt changes.

Pulldown Menu Location: CG-Survey > Mngmt > Point Groups
Keyboard Command: cg_create_bpf
Prerequiste:  Coordinate file