Latest Contributions by MelindaMorang

A junction source feature can participate in multiple connectivity groups, unlike an edge source feature class.  So, if you have two edge sources in different connectivity groups, you can assign a single junction source to be the "bridge" between the two connectivity groups by allowing it to participate in both groups.  The junctions will represent the transfer points which are the only points where the traveler can transfer from one group (edge source) to another group (the other edge source). ... View more

I just looked at the tutorial data more closely, and now I realize that I don't know what you're asking.  I'm not sure what a "transfer junction" is. I'm guessing that what you need is a line feature connecting your station entrances and your stops.  Is that right? The Points to Line tool is useful for this.  You will need to have pairs of points with a unique ID field so that a single line gets drawn to connect each stop with its appropriate station entrance.  So you might have to do some work to get the data in the correct format. If this is not your question, please clarify. Also keep in mind that the available transit service changes significantly on different days of the week and times of day.  You can estimate travel times, but the results of your analysis might not be very accurate at all.  It's hard to define what a "simple and general" result for this type of analysis even is. ... View more

Hello Destiny. I presume from your question that you have worked through the Creating a multimodal network dataset tutorial and are trying to replicate the network dataset structure with your own data.  The network structure used in the tutorial data is just an example meant to explain how network connectivity works.  It's not an "official" data model of any kind, so that's why you won't find any documentation about how to create "transfer junctions". Before I dig into that data to remind myself what the transfer junctions do, let me ask you a clarification question: What is the goal of your project? If you need to be able to use the public transit schedules in your analysis, the only way to do this is my creating a network dataset from your GTFS data using the Add GTFS to a Network Dataset tool.  That tool allows you to solve your analysis for a specific time of day and uses the actual transit schedules to generate a result that is correct for that time. The network in the tutorial does not use actual transit schedules.  It just uses a simple travel time estimate on the subway lines that is not based on a schedule. Let me know if this is sufficient for your purposes, and I'll try to answer your original question. [Asking because of my familiarity with your previous questions.] ... View more

Yes, that's correct.  When you add/load locations to your NA layer, the original points must "locate on" the network dataset.  This means that their original lat/lon location must snap to the closest part of the network, and this snapped location is considered the starting and ending point of the analysis.  If you want to model a parking lot or a long driveway, you need to include that as part of your network dataset.  Alternatively, for each location, you can set an added cost value using the Attr_[Impedance] field in the attribute table, where [Impedance] represents the name of the impedance attribute you're using for the analysis.  So if you know it takes an extra 5 minutes to get to your stop from the curbside, and your impedance attribute is called TravelTime, you can put a value of 5 in the Attr_TravelTime field in the attribute table for your Stops sublayer (assuming you're solving a Route). ... View more

Maybe this documentation page section will be helpful: Understanding network attributes—Help | ArcGIS Desktop  ... View more

Near and Generate Near Table will do more like OD Cost Matrix and calculate the distance from each origin to all destinations.  I'm not seeing a tool that would do it based on ID fields, but this is a little bit out of my area.  You could solve the problem by iteratively selecting the points with each ID one by one and calculating Near, using a python script or model, but this would probably be pretty slow. ... View more

Just sent you a PM through GeoNet.  You should be able to reply to it, I think. ... View more

Hmm.  All that looks correct, as it should be, since you built the network from the template anyway.  (Incidentally, Shape and shape_length basically do the same thing here, so it doesn't matter which you use.) I looked at your Service Area screenshots again, and I noticed two things: 1) "Use time" is unchecked in your Service Area settings.  You need to turn the time of day on and set it to something specific or else the transit stuff won't be used at all. 2) Although your Service Area extends all the way to the edge of your network, the service area break value is like 5.6E-3, which is really tiny.  So there's definitely some kind of unit conversion issue happening.  Since you used the template, it ought to be working, but maybe there's something wrong with the template. Would you be able to share your gdb with the network in it so I can take a look?  Just zip up the whole gdb and put it on a file share somewhere I can download. ... View more