Latest Contributions by RichardFairhurst

I would add a field called CASE_ID and calculate it all to 1 and set that as the case field, rather than leaving the case field blank. If that doesn't work, convert the shapeflle to a feature class in a file geodatabase (fgdb) and output to another feature class in the same fgdb.  I don't really test my tools to see if they work with shapefles, since I would argue no one should ever use them for geoprocessing.  I avoid them due to their poor performance and limitations. ... View more

Embedded cursors only works for small sets of data.  The larger the data grows the inefficiency becomes exponentially bad.  Loading a dictionary from the table with the data you want to read only with the unique combinations as the key and values of the fields to write in a list and then using an insert cursor based on the dictionary matches is incredibly fast.  I discourage everyone from using embedded cursors.  They are a poor solution. ... View more

I wrote the tool in this Blog specifically for use with the output of the Frequency Tool or Summary Statistics tool when multiple fields are used for the unique case values.  It creates a new Long field in both the original source and the frequency output to generate a single unique Long number to represent each multi-field unique combination.  It should handle all normal data field types and Null values.  The sort order of the unique field values should be correct for each field type (i.e., strings sort as strings, numbers sort as numbers, dates sort as dates, etc.) and the fields can be prioritized in any order.  The 10.3 version is better than the 10.2 version, but both work. ... View more

Because your data is in a Projected Coordinate System and using Linear Units, you can use the Attribute Assistant Add-In to automatically update an Acres field in a geodatabase feature class during an edit session.  You can download the Attribute Assistant Add-In as part of one of the Local Government Information Model templates, such as the Address Data Management template (press the Download button to install it). For the initial one time set steps you need to copy the DynamicValue table from the sample geodatabase into your existing geodatabase.  Then you should add a record to the DynamicValue table with the following settings: Table Name:  The name of the feature class that contains the Acres field you want to maintain. Field Name: The name of the field that will be updated to hold the feature Acreage ​​values. ​Value Method:  EXPRESSION Value Info:  [Shape.STArea​()] / 43560 (the formula to convert square feet to acres) On Create:  True On Change (Attribute):  False ​​On Change (Geometry):  True Manual Only:  False Rule Weight: Null or 1 Comment:  (Optionally you can explain the method ​​​settings and behaviors in more detail here), To make the settings work you have to add the DynamicValue table to any map where you will edit the feature class, make the Attribute Assistant toolbar visible, start an edit session on the feature class, and verify that the Attribtue Assistant button is enabled (it has a green exclamation mark in the button, not a red exclamation mark).  Now whenever you finish creating the geometry for a new feature or modify an existing feature's geometry and finish its Edit Sketch, you will see the acres field you configured automatically update to reflect the current feature geometry. If you manage Centerline data you should also copy the GenerateId, MasterStreetName, RoadDir and RoadType tables from the sample geodatabase into your existing geodatabase if you want to implement some of the other Attribute Assistant behaviors that are supported by the Address Data Management template. ... View more

The screen shot is consistent with what Dan pointed out, you cannot use Union when one of the event tables is a point event table.  Notice that the output event type setting is Line and that setting cannot be edited to change it to Point.  You can only create points when a point event table or feature class is used with any of the Intersect tools and points simply don't work with any of the Union tools. The workaround is to create two new fields to hold duplicates of the real measure fields of your line events. You should use the duplicate line measure fields for the inputs to the tool.  Do an Intersect with the points, not a Union.  Make sure the output measure field name is not the same as the original measure field names used by the line events.  The output will have a new measure field for the sign point location created by the tool, but it will also have the original measure fields.for the line.  Just use the two measure fields preserved from the line that were not inputs to the tool to create a line event layer.  The layer will contain line events with the original line data combined with the data of one of the signs it touched, and there will be overlapping lines that will match the full set of signs touched by each segment. In case what you really want is a single line event that has many columns of fields that combine the data for each and every sign along the segment into a single event, no tool does that.  A Pivot table could pivot one of the sign attributes into multiple columns from the output of the Intersect above, but it would not pivot multiple point attributes without a lot of effort. ... View more

I suspect when you converted the data to a cvs file ArcMap imports the field names that began with numbers differently.  Also, if you check the output of the Bearing Distance to Line tool the cvs file created I bet the 15yrDisplacement and 20yrSpread field names changed to begin with a letter. ... View more

Field names cannot begin with numbers.  So the 15yrDisplacement and 20yrSpread fields need to be changed to start with a letter.  I changed them to Displacement15yr and Spread20yr and the tool then worked directly from the xlsx file I downloaded.  The output table also should begin with a letter and not a number.  I figured this out when I ran the Excel to Table tool and it automatically changed the 15yrDisplacement and 20yrSpread column names to f15yrDisplacement and f20yrSpread.  Beginning field names with numbers has always been discouraged since it is known to cause issues all over ArcGIS. The tool actually does work with the negative length values.  It automatically reverses the angle and converts the length to a positive value when it encounters a negative length value, so if that is what you want you don't have to change the bearing or distance values for the rows with negative lengths.  The negative length lines are highlighted in blue in the picture below. ... View more

Laura: Lines with 0 distance are points, not lines, and the tool does not support drawing points.  You must assign a length value greater than 0 to those rows or eliminate those rows as Darren suggested.  You don't have to necessarily delete those rows if you use a layer/table view with a selection of only the rows that have a length greater than 0 as the input to the tool.  Potentially one approach to those rows with negative lengths is to select all of those rows and calculate the angle field to reverse the angle by adding 180 degrees to the angle (the tool should handle angle values that equal or exceed 360 degrees), then set the length to ABS([20yrSpread]) so that it is positive. ... View more

The Bearing Distance to Line tool fails due to the negative values in the 20yrSpread field.  It is impossible to create a line with negative length.  You either need to change all the values to their absolute value (positive), or create a new field and set it to the absolute value of the 20yrSrpread length.  If you need to reverse the line direction for some reason after creating it based on the signed value of the length in the 20yrSpread field, that would happen in a separate step. ... View more

Unfortunately both the Near Table tool and Near tool require an Advanced license. You could try using Linear Referencing, which only requires a Basic license.  To do that you would repeat these steps separately for the schools and then the parks: 1. First add a unique value field to the polygons that can be copied to another feature class, like a Long field that is calculated to be equal to the ObjectID of the polygons. 2. Convert your polygons into lines by copy/pasting them into a lines feature class with an identical schema to your polygons. 3. You then can use the Create Routes to convert the polygon outlines to Routes.  The Polygon ID would be your Route ID for each route. 4. Make sure the points have a unique ID field, then use the Locate Features Along Routes with the closest route option unchecked, the distance option checked, and a large search tolerance for the tobacco shop points. 5. Use the Summary Statistics tool to summarize the Point IDs and Route IDs as the case fields and get the minimum distance value in the summary to eliminate duplicate route locations along curved portions of the route. 6. The minimum distance values in the output could be averaged for each tobacco shop point based on the unique ID field using the Summary Statistics tool (works under a Basic license).  The Case fields should be just the Point IDs and summarize the Mean of the distance. 7. Join the summary back to the points and calculate over your averages. ... View more

You cannot add Null values with other values.  See Fezter's answer to this post for a Python method you should be able to adapt to your problem. ... View more

Post the calculation you used.  Did you build the expression using the expression builder field list?  Are you sure all of the fields are Double, Float, Long or Short fields?  Is the output field the correct type to hold the addition result (typically you should use either a Double or a Long output field).  Are there Null values in the fields you are adding together?  Is the data source a shapefile/dbf file or a geodatabase feature class/table.  Is it an SDE database?  What version of ArcMap are you using? ... View more