Latest Contributions by RichardFairhurst

With Feature classes it is possible to add one of the join FCs to a map twice.  One copy of the FCcan act as a join table and the other can act as a parent table of the join.  Definition queries should work on both the same way.  Transferring selection sets is the only problem, but select by location can deal with that partially. For one standalone table and one feature class this should also work,  Only standalone table to standalone table would not work this way. However, nothing will let you deal with one-to-many or many-to-many joins using ArcGIS without making a copy and performance of such joins sucks even in view only mode.  Access requires a desychronized edit mode to allow modifications of joined query tables like this, because there is delay in the update across all joins and because there is a risk that edits of a child record will not be correct when seen from another joined record. ... View more

Dear all I am using a polygon shapefile and I want to select the polygon with the highest value. I am trying to implement this in ModelBuilder using ArcGIS Desktop v. 10.1. Ideally I want to select the maximum record and then use that selection to conduct additional analyses. Any advice greatly appreciated. Thank you, Paul Generate a summary table and use the maximum value from it to do your selection.  Subqueries are very limited, so summary tables are the way to go.  A join back to the original to do selections allows you to continue the processing on the original dataset.  Be aware that Maximum only works for numeric fields, not text or date fields.  First works for text and date, but that dies not necessarily return the lowest alphabetic value or date value, just the first record in the table for the query criteria. ... View more

Thanks, But what I need is only the selection order,because i have many consecutive number to be populated with (in the field ). I want this done automatically based on selection. Is there any programming hints for C# Please guide; I am really type of bored doing this manually. Thanks again... I do programming in VB.Net and what you want is not possible in any language.  Nothing keeps track of a selection order as you have described it.  Once a second item is selected a cursor will read them in the order they were created in the table, regardless of the order you selected them, just like the field calculator.  The only way around that is with another field providing a sort order, but if you had that it probably would be in the field you are trying to populate.  At best you could select one item, press a button or hot key to assign the next unused sequence number and then deselect it and select another.  Only slightly better than typing the values in yourself, but perhaps a little easier.  Your database design or workflow is poor if it is truly dependent on this type of editing, because as you have seen it requires intensive manual intervention to work. In my jurisdiction this would not work well, because the next sequence number for a parcel is dependent on the book and page the parcel falls on, which may not be apparent to the program without a fairr amount of issues to overcome.  QC generally is manual in such cases. ... View more

Hi All, I am looking for ideas on 1) a symbol that exists or 2) one that I might make, to represent how an information sign relates to a person looking at it to orientate themselves to their surroundings. We have several signs placed around my place of work so that people and find there ways to buildings. What is happening is that some people when facing the signs (they are marked with a 'you are here' identifier) don't realise that some buildings may be to their left or right because the map is orientated with north to the top but the sign is erected facing east and the person viewing is facing west. I don't want to re-orient the map/dataframe, so looking for ideas on symbols that others may have seen or created and willing to share. Regards, Craig Orientation of point marker symbols is done with the angle field, which is an advanced symbol setting on the Symbology tab.  Two different coordinate orientations of the 360 degrees are available (geographic with north at 0 degrees and going clockwise, and arithmetic with due east as 0 degrees and going counter clockwise like a cartesian graph).  I use Linear Referencing to get an angle of orientation auto-generated for events on the line, which I then use to orient the marker relative to the line direction with a field calculation. Provide a screen shot of your current configuration if this answer is not what you are looking for. ... View more

Hi, Is there any tool in ArcGIS10.1 to convert road network data set from polyline to line. I have to import those data in TRANUS (Land use and transportation forecasting model). thanks Rishu There is an Export to CAD tool in the Conversion toolbox To CAD group. ... View more

Well i spent almost a day but finally i solved the problem with a python script. Share the script please.  This post is not much use to anyone (other than you) without it. ... View more

Thank you very much. I will give a try. Because the Intermediate table is somewhat protected by ArcMap and I have not really attempted this before, I looked at the help on these kind of relationships to verify the table can be exposed.  See http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//004t00000004000000.htm It appears you must add the relationship class to the map to make the tableview for the Intermediate table visible.  As a table it should have the Summarize option when you right click a field.  For starters verify you can do that.  It is possible that a copy of the Intermediate table would have to be created before ModelBuilder would use it in a Summary Statistics operation.  Take it one step at a time to get a better understanding of what you can do with the relationship class. ... View more

Hello friends,  I used the tool "ArcToolbox>Data Management Tools>Relationship Classes>Table to Relationship Class" to establish a relation (many to many) between   land parcels and   owners. I already had the intermediate table. The question is how can i make a thematic map that shows the number of owners a parcel has?  For example:  light blue color=1 owner  darker blue=2 owners  dark blue=3+ owners  Thank you You cannot do that directly from a many-to-many (Parcel to Owner and vice versa) or one-to-many (Parcel to Intermediate table or Owner to Intermediate table) relationship. You must generate a Summary Statistics table from the Intermediate table and use the Parcel values as the unique Summary case field. The summary will automatically generate a Count field. That count should represent the number of owners connected to the parcel (assuming uniqueness of each many to many relationship was maintained). Because the Summary table will be a one-to-one relationship to your Parcels, you can join the Parcel features to this summary table. That join will allow you to create the map you want to make. Optionally you can calculate the count values into the Parcel feature class. There is no way to have the map respond to live edits. You must regenerate the Summary table to reflect edits to the many-to-many relationship. A model should be part of your workflow to make tha easy and fast to do at the end of your edits or during the edit process for validation. ... View more

Hey everyone, I have a large polygon set and I want to be able to do some sort of spatial analysis to determine if adjacent polygons contain the same attribute value from one field in the attribute table (i.e. I have a field called SOIL_TYPE. If 2 adjacent polygons both have the the same SOIL_TYPE, they should be flagged and merged as one). I'm thinking there must be a tool/python script that will do this, but I've searched around and haven't com across anything. If anyone can point me in the right direction, I'd appreciate it. Cheers, Mike Sounds like you need to use the Dissolve tool to me.  It creates a new output, which could be used to validate the merges and then apply flags to the existing data if that is what you really want to operate on.  Once flagged then some kind of python script could do the merge in te original dataset. ... View more

Hi,   We have a number of databases in addition to our sde geodatabase and we often create a connection to and pull in these non-sde tables and views and use the data as layers, etc.  It seems that we're unable to edit these tables through ArcMap.  When we try we get the error "no editable layers".  These tables are editable by the same user using SQL tools, so permissions are fine.    I guess my question is this:  Can ArcMap edit non-SDE tables from other databases?  It seems like it should be able to, but just isn't.  Maybe there is something I'm missing?  I've read docs and surfed the forums but coming up empty. Thanks! ken. What are the other databases you are connecting to?  What kind of connection are you creating (ODBC or what)?  Sometimes drivers are more oriented to viewing data than to supporting full editing capabiliies, so the specifics probably matter. ... View more

I have a question about this. I'm doing something similar, but the difference is that I'm connecting airline flights across different time blocks (600-700, 700-800, etc) I've already made Polylines for each time block, but I want to connect separate flight paths (ie, Dallas to Houston connects in Houston for a new flight path Houston to Amarillo, etc) but I don't know how to retain the time block and connect the Polylines into a single flight route for the entire day. Any suggestions? From the sound of it, you have multiple segments that make up a complete flight path that are divided at each time block.  You want a single line that connects all of these segments.  You will have to drop or generalize the timeblock information in the single line full flight path.  A Min/Max summary could retain the end values of the time blocks or you could create a comma separated complete list in a single field, but either way you lose some of the details of the separate line segments. Therefore, you really need to maintain two separate feature classes to fully represent the data you are working with.  You can create a relate between the two feature classes to move back and forth between the two representations. As far as connecting the line segments, create a Linear Referencing Route from the segments based on Flight ID and use a summary value for the Time Blocks (Min?Max).  Make sure all of your time block lines are drawn to point toward the end time block position.  Calculate the Time Block ranges into two fields (a From Time and a To Time) and use these fields as the From Measure and To Measure values for the Create Route tool to correctly order the segments and assign mesures to the Route that will be based on time.  Some adjustment to the time blocks will be needed if two flight segment connect across the midnight barrier to ensure that the path on the preceeding day connects to the path on the next day.  Make sure to override the Environmental Settings options for the Create Route tool to set the M Range, M Resolution and M Tolerance to hold fractional values (by default the Create Route will use only integer measure values, which is rarely useful, but only the Environmental Settings give you a consistent way to override that behavior). With this route you can create an event table to show segments along the flight paths covering any time range you want that fits within the flight times.  For example you could get a segment for 625 to 750 with no problem and no need to create new feature geometry, only a row in a table or spreadsheet with the Flight ID and the From and To time interval you want. If you are connecting several Flight IDs together, you would need to create a new field to hold a Total Day Flight ID that you would have to create.  As long as the segments that make up that set of flights do not have overlapping time block values on any segment, the Create Route tool should be able to combine them all.  Of course you will again lose some detail with this line that is preserved in the separate Flight ID paths and the time block paths, so this should probably be a modeled derivative of the more detailed data and you should perform maintenance on the finest level of detail that makes sense. If you are looking to solve route optimization problems, then you need to use Network Analyst once you have a working network of flights. I hope this helps. ... View more

I am working on a similar project however I also need a way to automate the creation of the sidewalk centerlines. Any ideas other than buffering the road center line? Also, I am working through the steps to create the crosswalks and already having trouble with step one. I attached a picture of my results. Any help is appreciated! [ATTACH=CONFIG]21557[/ATTACH] I will address the problem with step 1 first.  You have not zoomed in enough for me to tell if the input to the Lines to Polygon tool was in the correct format or not.  The expected line input is a Road Casing line set, such as the frontages of Parcels lining the road.  If you used a single Centerline network with lines in the middle of the road, that input will not work.  So show me the line set you used at a scale where I can make out the boundary between a road outline and property outlines.  Your output could be correct,but you need to do the classifying process if it is. For the Sidewalks, I personally do not care if they trace the sidewalk exactly, so if you want an automated process to follow aerials, I don't have one.  I just use Linear Referencing Events with a 30 foot offset for all roads.  The lines do not overlay the aerials accurately at all and the line cross through the street intersections and do not go around the cul-de-sac bulbs.  It works for my needs and got the job done for the time and budget I had, but it is not for everyone. So for my example in this thread I just used Parcel frontage lines.  Those lines do not trace sidewalks either, but they have more similarity to actual sidewalk locations. Accurately following aerials would either require lots of time manually digitizing or paying for expensive data capture processes, such as having a vehicle laser/radar/lidar scanning your actual roads by driving them or an aerial photo conversion program that no one is going to give you for free.  I have not seen any aerial interpreters that I really liked for the price, or they were not targeted for roads/sidewalks.  If I knew how to program that I would charge for it and not give the code away here on the forum. ... View more

This seems to be working other than that the table that created has all zeros for the FMEAS and TMEAS and cant be sorted.  It is however selecting the right parcels based on the Route Identifier, it is just not populating the measurement fields. Make sure to go to the Environmental Settings for Create Route and set the M Extent, Resolution and Tolerance to handle fractions.  Without Environmental overrides it tends to create measures in whole numbers, which means that fractions of a mile turn into 0.  Calculate M values for the Route To value into a field to verify they are not 0 with a Python Calculation: !Shape.Lastpoint.M! If the fractional value is not a problem, then run Intersect and use the formula to extract M values from the intersected lines (they will transfer). ... View more

I need to create a list of parcels that are intersected by a pipeline.  That list has to be ordered from the beginning of the line to the end.  I have hundreds of lines so automating this would be fantastic.  I can create the list of parcel owners with a select by location but putting them in order is where im stumped. Is there a way to number polygons along a line from beginning to end? Use the Create Routes tool in the Linear Referencing tool set to convert your pipelines to Routes.  I assume each pipeline has a unique ID that can function as the Route ID field.  Assign measure in a way that makes sense, probably that respects the direction of the line.  You can create 2 fields.  One will be 0 for the From Measure, the other will hold your To Measure and can be calculated to equal your line length. Use Locate Features along Route.  This will create a duplicate of your APN with three added fields, the pipe Route ID (your pipeline ID) and the From and To measure where the feature intersected the line.  Sort by Route ID and From measure (Ascending or Descending as you like) to list the APNs in the order that they fall along the road.  You also will have an event table that can map the linear overlap of the parcels on the line. ... View more

David: I have made another correction to the code in the UniqueValues property.  The code below handles two cases where code results in unhandled exceptions.  The first occurs when the cursor for the class is Nothing (unassigned).  The second occurs when the cursor returns Nothing for the row value (the cursor had no records).  In both of these cases I set the UniqueValueCount of the class to 0 and return an empty Enumeration, which I believe matches the behavior of the original IDataStatistics property.     Public ReadOnly Property UniqueValues As System.Collections.IEnumerator Implements IDataStatisticsECL.UniqueValues         Get             If m_Cur Is Nothing Then                 m_UniqueValueCount = 0                 Dim arra(-1) As Object                 Dim noCursor1 As New ValuesEnum(arra)                 Return noCursor1             End If             Dim row As Row = CType(m_Cur.NextRow(), Row)             If row Is Nothing Then                 m_UniqueValueCount = 0                 Dim arra(-1) As Object                 Dim noRow2 As New ValuesEnum(arra)                 Return noRow2             End If             Dim dic As New SortedList(Of Object, String)             Dim iFeild = row.Fields.FindField(m_Field)             'loop through the data and get the unique values             Do Until row Is Nothing                 If dic.ContainsKey(row.Value(iFeild)) = False Then                     dic.Add(row.Value(iFeild), "")                 End If                 row = CType(m_Cur.NextRow(), Row)             Loop             Dim arr(dic.Count - 1) As Object             Dim arrInd As Integer             dic.Keys.CopyTo(arr, arrInd)             m_UniqueValueCount = arr.Length             Dim n As New ValuesEnum(arr)             Return n         End Get     End Property ... View more