Latest Contributions by HardolphWasteneys

kvijaykar, If you cut the village polygons with the edge of the threat polygon and use a numeric domain for your population number field with a Split Policy called Geometry Ratio, the resultant polygons will have population numbers proportional to the areas of the splits.  This can also be accomplished by preserving the original village polygon area in a field and calculating the proportions of the new area to apply to the population, which would be useful if you are stuck with shapefiles. You can see the details of the cutting polygon and geometry ratio process in my recent post in  http://forums.arcgis.com/threads/56094-Trying-to-divide-a-large-amount-of-polygons-with-a-single-line-shapefile You could also employ Analysis Tools > Overlay Intersect with a polygon output between the Threat and Village polygons to select villages and cut villages within the threat zone. To get an ouline polyline from the Threat zone there are numerous ways including a couple of simple scripts in ArcGIS 9.3  Samples > Data Management  > Write Features To Text File and the companion reverse Create Features From Text File .  Just input the polygon feature class into the first script, edit the header in the output text file changing polygon to polyline, save and run the second script to generate the polyline. hope that works for you. Hardolph ... View more

Samantha, Please follow these Steps to avoid further confusion: 1.  go to your original spreadsheet and re-label the columns Field_Y_Latitude (the ones like 33.159106) and Field_X_Longitude (the -97.105016 ones). 2. resave the sheet as a .csv file called "XYPoints.csv" 3.  start ArcMAP and run the Add XY Data tool browsing to input "XYPoints.csv" 4. set X Field: = Field_X_Longitude and  Y Field: = Field_Y_Latitude. 5. at the bottom of the box hit EDIT... and Select in Geographic Coordinate Systems folder  North Americafolder:  "North American Datum 1983.prj "which will show up as  GCS_North_American_1983 6. In ArcMAP table of contents Right-Click on the "XYPoints.csv Events" layer and  Data > Export Data and specify the coordinate system as the layers source data in whatever file format you want Shapefile or Feature Class. You can then either do step 6 again and use your Data Frames Projected coordinate system (assuming you have set it to that of a base map in Texas State Plane) for a projected shapefile output or use the Data Management > Projection and Transformations > Project tool and output your data into Texas State plane or whatever. All the other posts have given correct advice, but don't bother trying to find a "solution"; you've just run into a common problem mixing up X and Y for Latitude and Longitude.  Maybe it just sounds better that way. Hardolph ... View more

Adam,  For ArcView 9.3 or 10, the simplest and most complete way I can suggest for doing both the split of your polygons and calculating the ratio is to use the standard EDITOR toolbar Task:  "Cut Polygon Features" http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Splitting_polygon_features  with a merged copy of the polylines in the shapefile/FC as a cutting feature and importantly transfer your polygon shapefile to a Geodatabase Feature class, set up a numeric attribute range domain in the GDB with a SPLIT Policy called Geometry Ratio  http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=An_overview_of_attribute_domains.  This domain can be applied to area and other numeric attribute fields to proportionately divide the attribute values based on the proportions of the split.  Of course the shape geometry of the polygons will be automatically calculated in a Feature Class anyway so if all you are looking for is area that will be present and you can do it without getting into domains.   To calculate the ratio of one side vs. the other you would map the Shape_Area field of your original pre-split polygons into a non-domain controlled field to be retained in both splits as a simple attribute and then run Field Calculator in the attribute table to calculate a ratio of the split area (or the Shape_Area) to the original area in a new field.  Method: 1. Create a File Geodatabase with a numeric range domain with the Geometry ratio split policy and import your shapefile to new Feature Class with whatever fields you want controlled by the domain for proportional splitting purposes and just set the range big enough to cover all of them.  2. Add a new field to the polygon FC and and populate it with the SHAPE_AREA field using Field Calculator. 3. set up a scratch polyline file in ArcCatalog and bring into your map 4. Start an EDITOR session with Task: Create New Features and Target: the scratch FC5. select all the polylines that you want to use as splitters, whether from one shapefile or Feature Class or many (can be in different workspaces too) 6. with the edit tool on the map Right-Click COPY and Right-Click PASTE (makes a safe copy of the lines geometry in your scratch polyline FC) 7. leave the lines selected and hit EDITOR >> Merge and choose any feature as the merge to feature for symbology (it does not matter) 8. Change to TASK: CUT POLYGON FEATURES and Target: the new POLYGON FC. 9. Select the polygons to be split either in the attribute table or on screen (this will activate the SKETCH tool (pencil) in the EDITOR toolbar) 10. select the SKETCH tool and hover over any part of the Merged Polylines (to be sure I set snapping on the polyline FC and MapTips will show when it is being hovered over or snapped to) 11. Right-click and hit REPLACE SKETCH and then F-2 or Right-Click and Finish Sketch. you will now have split the whole works of polygons and can go into the Polygon attribute table and to do the area ratio calculations using either the domain controlled fields with the Geometry Ratio split policy or add a new field and use Field Calculator to find the ratio of the  SHAPE_AREA / "original area" fields. You could also do this with just a shapefile by using Calculate Geometry on a new numeric field and storing away the AREA then doing that again in the SPLIT shapefile and calculating the ratio but this would do nothing for other numeric attributes that you might want to proportionately split. That's quite a few steps but most of it is standard procedures that you can find in help files (except perhaps the merged polyline cutter). if you need any clarification, don't hesitate to post again Hardolph ... View more

Jason, Individually, this can be done as an editing task using the distance-direction edit tools, but as a geoprocessing task the best I can suggest is using some good old trigonometry to add the offsetting x and y to the X-Y coordinates, output a table and reinput to create a new feature class (Add XY Data tool in 9.3; and something similar in 10). steps (9.3 ArcView): 1. explicitly show the original point coordinates in the attribute table either by adding fields and calculating Geometry or more conveniently using the Data Management > Features > Add XY Coordinates tool (gives default fields POINT_X and POINT_Y). 2. add two more blank fields of numeric type double called NewX and NewY (or whatever) . 3. use the Field Calculator on those fields to calculate the appropriate projected point coordinate (input your actual direction and distance fields) 3a.  NewX = POINT_X + Distance_Field * Sin (Azimuth_Field*pi/180)  3b.  NewY = POINT_Y + Distance_Field * Cos (Azimuth_Field*pi/180) where pi = 3.1415 to convert degress to radians for trig function 4. In the attribute table Options use Export and create an output table (this is most conveniently done in the same workspace as a geodatabase table but can be even a text file). 5. use the Add XY Data tool to create a new shapefile or feature class from the output table using the NewX and NewY coordinates and making sure you use the Edit... button on the dialog to define the coordinate system. 6. go to the Event_Table created by the tool in ArcMAPand use the right click menu DATA > Export Data to output a new feature class or shapefile.  I don't know if ArcGIS 10 has a geoprocessing tool to do that, but for ArcView 9.3 that is about the only way without the Survey Analyst extension or COGO in ArcEditor or ArcInfo good luck, Hardolph ... View more

David, some specific examples: In eastern Tijuana the WGS-84 defined electoral boundary shapefile fits well with street patterns, but in western Tijuana it does not and appears shifted to the west. What appears to have happened to the western Tijuana data is that it was collected in WGS-84, but mistakenly redefined as NAD27 and then projected to WGS-84 perhaps along with data from eastern Tijuana that was truly in NAD27 coordinates and correctly projected. Likely this has happened in other parts as well.   To correct a specific sector of the data you would clip it out and project to NAD27 then simply redefine the data as WGS-84 in the properties for the shapefile in ArcCatalog. Beware however that while there seems to be a straightforward transformation mistake between NAD 27 and WGS 84 in the Tijuana data divided along some shifting line, elsewhere it could have been more political. Hardolph ... View more

Chris, hard to speculate on one malfunctioning Domain-filled FC without seeing the schema and FC structure, but I'd think there was something corrupt about the FC in question if the domains work elsewhere.  Random suggestions/questions: 1. are you using subtypes? 2. build a test FC using the domains that work and some that don't if they are not already being used in the functional FCs. 3. how are you resetting the domains in the erring FC?  No subtypes set, just looking at the Fields tab?  The domain selection menu should only pick ones that have the right field type so that shouldn't be the issue 4. make a new FC and import the structure from the problem one. 5. make sure you have not pulled in a similar FC from outside the gdb 6. or selected the wrong workspace for your EDIT session 7. if the domains are not used elsewhere have a look at them for format; run Domain to Table to check coded values etc. and make sure coded value field type corresponds to the field type used for the various domains in the FC (though I can't see how it could have been selected if not). Hardolph ... View more

David, I had a look at the data superimposed on some basemap imagery in various projections and using different assumptions about the original data coordinates and there seems to be variability in the fit west to east almost as if it was compiled from different data sets: some in NAD27 and others NAD83 or WGS-84.  On the west coast the data fit reasonably well as is, but as you go east they shift and look like they were NAD 27 coordinates or even NAD83 projected to NAD 27 a couple of times.   Some places they are in between what you would get using the WGS_1984_to_NAD_1927_18 transformation. Hard to judge the data in places outside the cities where the boundary lines are generalized on landforms and many places in the road networks there are ambiguities where there are few distinctive road shapes. However, I'd be concerned about how the dataset was put together.  It appears to have been compiled in geographically variable geographic coordinate systems including NAD 27 and NAD 83 and maybe even some incorrect transformations. Hope there is a simpler explanation... good luck, Hardolph ... View more

I have searched the forums but haven't found anything similar with my task. Your help, guidance would be appreciated. I have several polygons in a shapefile with a Priority field. How do I clip the polygons based on this field? Thanks in advance. Jeffrey Jeffrey, the simplest way to do this is using the EDITOR Clip: Assuming you have a small number of polygons in a single shapefile (or FC) with a small number of priority levels (e.g. 1 to 5) you can sequentially select single features either in the attribute table to see the priority level or manually with the edit tool (perhaps labelling the polygons with the Priority Field and then in the EDITOR menu hit Clip and using 0.0 buffer distance and the "Discard the area that intersects" option. This will acheive what you want though limited to one clipping polygon at a time, and it will drill down through all other polygons not only in the shapefile but any others intersected as well. The CLIP Tool in ArcToolBox will clip with multiple features selected at one time, but creates a new feature class preserving the area intersected, rather like the intersect tool, rather than chopping out the intersected area in the shapefile. Hardolph ... View more

Chris, I've used Trimble GeoXTs with ArcPAD for geological mapping and routinely collected the data as several separate polyline feature classes with various attributes and points for a variety of geological observations.  I loaded the data onto a workstation where I created polygons delineated by the various polyline features and directly from them.     From what you describe I presume you have a large polygon feature (the ROW) within which you have GPS created polylines for the wetland boundaries that continue across the ROW boundary.   There are several ArcView 9.2, 9.3, 10 options for creating polygons directly from polylines as well as creating polylines from polygons.  The general idea would be to first create a polyline from the border of the ROW then complete a polygon for each wetland using that boundary and the polyline edges of the wetlands.  You can set the whole works up and do it in one operation to create polygons for all the wetlands.  I routinely use the auto-complete polygon Task to create polygons from multiple polyline feature classes in ArcView 9.3 (also works in 9.2 and 10). This involves copying and pasting the polyline features into a scratch feature class and merging them, then running Auto-complete with a few tricks similar to the method described for splitting polygons using existing lines.   I've posted variations on the method several times http://forums.arcgis.com/threads/6288-Editing http://forums.arcgis.com/threads/518...5524#post15524 Here's the step by step procedure I use (previously posted and edited): 1. start by making sure the line segments are either snapped together or overlap (optionally, set snapping in the polyline layers that you want to use). Any existing polygons present within the area of interest (your ROW polygon) will create holes in the generated polygon fabric so turn those layers off. I set up a scratch polyline feature class in the current workspace/geodatabase for temporary use to avoid messing with the original field data or attributed and symbolized polylines. 2. select all the polyline segments with the edit tool or by any select by attribute method in the attribute table (these can be in multiple workspaces/geodatabases as long as they are selectable) 3. set Task: Create New Feature and Target: the scratch polyline Feature Class 4. right click with the edit tool in the work area and hit copy, then right click again and hit paste (this creates a set of unattributed lines in the scratch feature class and deselects the ones selected from the original feature classes; ctrl-c, ctrl-v won't work for this ). 5. In the EDITOR pulldown menu hit MERGE, and use any of the lines as the one to be merged with. 6. leaving the merged line selected change "Target:" to a polygon FC and "Task:" to "Auto-complete Polygon" 7. using the SKETCH tool allow it to snap to the selected merged line anywhere (do not left click) and RIGHT-click and select "replace sketch" from the pull-down menu. 8. all the vertices of all the lines should become highlighted; hit F2 or right-click again and hit Finish Sketch. For map display purposes I then overlay the original polylines with their variable symbology as the borders for the polygons. Here's a couple of recent threads where I outlined some similar methods if that isn't explicit enough: http://forums.arcgis.com/threads/678...hlight=polygon http://forums.arcgis.com/threads/269...hlight=polygon http://forums.arcgis.com/threads/306...hlight=polygon http://forums.arcgis.com/threads/51008-Unable-to-construct-polygons-from-lines-in-ArcGIS-10 Replies to that thread indicate it works in 10 as well as 9.3. The method for creating a polyline from the ROW polygon involves a script that creates a text file of the polygon vertices and then simple text edit in the resulting file substituting the header Polyline for Polygon and running the Create Feature from Text script on the saved file to make the polyline.  http://resources.esri.com/help/9.3/ArcGISDesktop/com/Gp_ToolRef/data_management_samples_tools/create_features_from_text_file_samples_.htm   or  http://resources.esri.com/geoprocessing/index.cfm?fa=codeGalleryDetails&scriptID=15945  After creating the polygons I would then attribute them from the point features lying within them using the Attribute Transfer Tool. good luck, Hardolph ... View more

Peter, The Autocomplete-Polygon editing task works only on the assigned target feature class containing the polygons so no mistake or bug there. I suppose that answers your question and you may already have other means of dealing with the consequences: However, there are many simple ways of handling the separation of features created in one feature class into others. The simplest way for your work flow, as I understand it, would be to continue digitizing the field and dams together using autocomplete to maintain common boundaries but: 1. assign a distinct value to the dam polygons made in your Crop Fields FC 2. at some point open the Crop Fields attribute table and use the select by attributes function to select all the polygons with the dam attribute you assigned (or just pick them with the edit tool) 3. change the EDITING functions to TASK: Create New Feature and TARGET: Farm_Dam FC 4. use the edit tool in the Data View and transfer the polygons to the Farm_Dam FC by the following: 4a. right click "COPY" 4b.  hit DELETE (or right click and "delete") 4c. right click "PASTE". That sequence will cut the dam polygons from the Crop Field FC and create them in the Farm Dam FC where you can then edit their attributes. ... Numerous other ways of handling all this including splitting the polygons with dams,  not using Autocomplete and starting with just polyline outlines etc.    ... All fairly standard editing procedures. Hardolph ... View more

This is Normal:   You need to export the data from the layer file created by the ADD XY tool in order to have a populated attribute table.  Just right click on the layer select DATA then export Data and create a shapefile from that.  The xy points should have plotted out when you use the ADD XY tool. If not you may have formatting issues, but not likely if you've successfully done this before.  Anyway, saving the xls file in csv format will help as well as checking to be sure you have numeric contents in the first 6 rows in the excel file. Hardolph ... View more

Hi Ryan, Melita is correct about the volcano data: you've ADDED them as X-Y data to a projected Data Frame calibrated in meters that has its origin at Latitude 0,  Longitude 0 so the point for e.g.  Pantelleria, which should be at 1058938 E, 3928821 N on a Robinson projection (more of an asthetic display) comes out at 36.46 m N ,  12.01 m E of 0 degrees Lat and Long, because the numbers, which should have been indicated as degrees of Lat and Long were interpreted as meters.  For starters you can re ADD_X-Y_Data the table of volcanos specifying a Geographic Coordinate System such as WGS-84 and they will plot up as I previously observed. The sytematic mistake in the coordinate data for the volcano is not the coordinate system, but that the decimal digits are not decimal degrees they were supposed to be minutes, which is why they all plot off to the south or southwest of true (notice they are all less than xx.60).  See the inserted map of the Tyrrhenian Sea showing the misinput locations in green pentagons and the corrected locations in red triangles.  I just divided the decimal part by 60 and added the full degree digits and they plot correctly.     [ATTACH=CONFIG]12883[/ATTACH]   Table of correct Volcano coordinates ObjectID Volcano           Latitude Longitude 1 Lipari              38.47 14.93 2 Palmarola  40.93 12.85 3 Pantelleria 36.77 12.02 4 MonteArci 39.77 8.73 For your obsidian site locations, once again make sure you enter the coordinate system of the X-Y data when you use the Add-XY Data tool or they will plot on the equator since you have used a base map in a Projected Coordinate system.   Like the Volcano data when plotted they appear to be highly approximate since some of the points plot out to sea, but unlike the volcanoes I don't know where they are supposed to plot and there are several coordinates that have decimal digits greater than 0.60 so they can't all be minutes.  I'd check the source of the data and how they were transcribed.  There also seem to be errors in the attributes as exemplified by the relatively precisely defined point for Gaione, Italy at 43.7034, 7.2663 that plots in Nice, France. Hope you are able to sort it out once you get beyond the initial data plotting issue. Hardolph ... View more

Giles, The main problem with using a UTM projected output for your project is that you have to cross 2 UTM zones to cover Libya and so you will have a lot of angular distortion.  You will also have to choose between Zone 34N and 35N. [ATTACH=CONFIG]12839[/ATTACH] The attached image shows the low res version of the files you mentioned in WGS-84-UTM Zone 34N projection.   I just georeferenced the smaller raster from the NOAA site in WGS-84 using lat-long coordinates and links to the shapefile rather than downloading the 158 Mb Geotiff.   If you looked at the whole bathymetric map across the Mediterranean in that same Zone 34N  UTM projection it forms a broad curve centered about the UTM zone of choice, which is not really appropriate.  So it is probably better to use something like Africa Albers Equal Area Conic projection for your final map.  This is shown in the next image with the same files.  It preserves areas better; i.e. is relatively equal in scale N-S and E-W.[ATTACH=CONFIG]12842[/ATTACH] You can also easily use some of the on-line imagery and boundary data from the "Add_Data_From_the_Resource_Center..." under the File menu, which I included to show the present/previous political boundaries. Hardolph ... View more

Alan, Megan, What kind of feature are you trying to buffer? I cannot see a direct way of using the BUFFER function to do this However, if what you are looking for is a shadow line at a particular distance and direction from the original feature, for example a curving polyline there are simple ways of producing this with the EDITOR: 1. in an edit session select the feature and use Right-click COPY, then Right click Paste to create a duplicate feature in the same place 2. then pull down the EDITOR menu and select MOVE and input a desired X-Y offset for the shadow line and hit enter. This will produce and exact copy of the feature at specified X-Y offset which is just another way of specifying direction and distance. If you want to stick with direction and distance you need to be more familiar with editing functions and snapping environments but it works quickly too: 1. start an edit session Create New Feature with Target: a polyline feature class and set snapping on ENDS. 2. using the sketch tool, snap to an Target END point on the feature and left click to make a starting vertex and pull away to start a line. 3. either right-click for a menu and hit "direction-distance" or type CTRL-g to get the same input box and input the direction and distance you want for your shadow buffer. Hit F-2 to finish the offset line. 4. duplicate the feature using the "copy Features Tool" on the Advanced Editing toolbar or use copy and paste and some arbitrary offset to separate the features. 5. select the copied feature with the edit tool and move the selection anchor to the end of the copied feature ( hit CTRL and hover over the small "x" then left click and drag the "x" until it snaps to the end of your feature. 6. move the feature with the edit tool until the END pt snaps to the end of the direction-distance line and you have your shadow line. What you do with it after that is up to your preferences; You could fill in the other end of the area with a line and convert the thing to a polygon and shade it. Anyway, it is sort of a fun editing task, sorry I can't see a way to use the buffer tool. selection anchor 1.[ESRI software] In an ArcMap editing session, a small "x" located in the center of selected features. The selection anchor is used in the snapping environment, or when rotating, moving, and scaling features. ... View more