Latest Contributions by XanderBakker

Hi all, I have been working with multiband images and on calculating standard deviation I am not sure what happens ? So can some one explain how standard deviation is calculated for a multiband image? Usually its a single band operation so how is it dealt with in ARC GIS? Thanks and Regards Samee Hi Samee, Not sure which aspect you refer to, so I�??ll try to tackle a few. Visualization of multispectral raster data When you display a multispectral image you have the possibility to stretch the bands before the Red, Green and Blue components are combined to  a color. One of the stretch methods is �??Standard deviation�?�. In this case it is calculated per band for all cells. More info here: http://resources.arcgis.com/en/help/main/10.2/index.html#//009t00000059000000 If you look at the explanation in the �??Raster data statistics�?� you�??ll see that: "Statistics are calculated for each band; if there is more than one band in the raster dataset, the statistics for each band are present. You can see that the parameters used to build the statistics are listed. The statistics that are calculated include the minimum and maximum pixel values as well as the mean and standard deviation of the calculated pixel values�?�". More info here: http://resources.arcgis.com/en/help/main/10.2/index.html#//009t0000001s000000 Statistics (raster) functions There is also the possibility to make use of focal statistics functions (on a single band data). In this case a �??virtual�?� new raster is created where each cell value will be the result of a standard deviation in a 3x3 or 5x5 moving windows. More info here: http://resources.arcgis.com/en/help/main/10.2/index.html#//009t00000058000000 In general more info on raster bands you�??ll find here: http://resources.arcgis.com/en/help/main/10.2/index.html#//009t00000005000000 Kind regards, Xander ... View more

Now the API example shows a convenient method that takes in all of the parameters of the call and returns the result of the call.  But it does not show the intermediate step which is computing the cost factor array.  And since I'm new to ArcGIS I'm not even sure what a raster is.  🙂  I've only known rasters as a type of graphics. Hi  Michael, That's quite a challenge you're facing... Let's start with the definition of a raster. I Think the link to the page "What is raster data" should get you started on that topic (I've included links to ArcGIS Help 10.0 and 10.2, since I don't know what version you're working with): http://resources.arcgis.com/en/help/main/10.2/index.html#//009t00000002000000  10.2 http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/What_is_raster_data/009t00000002000000/ 10.0 Everytime I Google the topic I get the documentation for the ArcGIS client or I get that theoretical discussion you included the link of.  I don't get any documentation on the C# code for creating those values programmatically.  Do you see the distance and what I'm trying to get an answer to? Since you what to know how you can create raster data programmatically, the link to this 10.0 Help page ("Performing a spatial analysis operation using objects") will provide you information on how to access raster objects from code and process them: http://help.arcgis.com/en/sdk/10.0/arcobjects_net/conceptualhelp/index.html#/Performing_a_spatial_analysis_operation_using_objects/00010000048n000000/ In order to analyze raster data you will probably need a Spatial Analyst extension. The 10.0 ArcObjects Library Reference (SpatialAnalyst) can be found here: http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#/ESRI_ArcGIS_SpatialAnalyst/004000000141000000/ But a raster???  And how do I know the resolution of the raster that was sent to me in that first call? IRasterProps::MeanCellSize (ESRI.ArcGIS.DataSourcesRaster) is used to access the cell size. http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#/IRasterProps_Interface/001q000002zp000000/ To create the cost raster (speed to cost conversion) you will probably use a raster or vector layer containing information on speeds. If this information is static, you can do this manually one time, but if this is dynamic data you should probably do this by code. From vector (polygons with attributes on speed), first calculate a new column transforming speed to cost as explained earlier. Then convert the features to raster. See snippet here: http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#//00490000000z000000 From raster data you would probably use some raster algebra to obtain the desired cost raster. Snippet here: http://help.arcgis.com/en/sdk/10.0/arcobjects_net/conceptualhelp/index.html#//000100000165000000 I think you might obtain more helpful information if you post this thread in the ArcObjects forum: http://forums.arcgis.com/forums/20-ArcObjects-SDKs Hope this gets you started. Kind regards, Xander ... View more

The number of points in my output point feature class in the same as my input point feature class (My join operation is set to JOIN_ONE_TO_ONE). ... I have checked the original attributes within the polygon layer as well to make sure that polygons only have one vegetation value assigned. Hi  Sunelle, What I don't understand is that there are the same amount of points and a single point may have two vegetation types joined to it, while the polygon layer only defines one vegetation type. So there are more vegetation type columns in the resulting point feature class? The only reason I can imagine for this to happen it that you joined the vegetation polygon layer twice to the points, once before and once after changing something related to the projection... Could you post a small part of both layers to see if this can be reproduced? Kind regards, Xander ... View more

Hi, I am busy spatially joining the attributes from a polygon layer (regional ecosystem information) to a point layer (scat survey sites). When I complete the spatial join (join features based on polygons which the points lie completely within) I find that the attributes from multiple polygons are joined to each of the points when the point only lies within one polygon (e.g. point 1 = vegtype1(wetland) AND vegtype2(non-remnant)). I suspect this may be due to the fact that the layers have different coordinate systems. I have attempted to project the layers in one coordinate system and reduce the XY tolerance however these changes don't seem to help. Does anyone have any suggestions. Sunelle 😄 Hi Sunelle, Assuming it isn't the result of differences in projections (and it is always wise to use the same projection when combining spatial data), there can be other reasons. Let's have a look at the help: http://resources.arcgis.com/en/help/main/10.2/index.html#//00080000000q000000 I understand that the number of points in your output point feature class is higher than the number of points in your input featureclass. Is that correct? If so, then I assume that during the spatial join your "join_operation" is set to "JOIN_ONE_TO_MANY". From the 10.2 Help: If multiple join features are found that have the same spatial relationship with a single target feature, the output feature class will contain multiple copies (records) of the target feature. For example, if a single point target feature is found within two separate polygon join features, the output feature class will contain two copies of the target feature: one record with the attributes of one polygon, and another record with the attributes of the other polygon. If you look at an input point that is found multiple times in your output and you perform an identify on your polygons, how many polygons are found at that location? If this is more than 1, your polygon feature class may contains regions (overlapping polygons). Kind regards, Xander ... View more

Can the weighted overlay tool be used with just Vector data (no raster layers)?  For instance I want to prioritize the installation of signaled crosswalks based on proximity to schools, recreational facilities, multifamily housing, etc. Hi Susan, The Weighted Overlay analysis only works on raster data: http://resources.arcgis.com/en/help/main/10.1/index.html#//009z000000rq000000 If you want to perform this analysis in vector format, you will need (preferably) polygon data of all aspects and perform a Union (or multiple unions if you don't have an Advanced/ArcInfo license): http://resources.arcgis.com/en/help/main/10.1/index.html#//00080000000s000000 http://resources.arcgis.com/en/help/main/10.1/index.html#//000800000010000000 This will result in a polygon layer with smaller polygons and mixed attributes of all your input layers. Then in the attribute table of that feature class, you will have to use field calculations to perform a personalized "weighted overlay". Can you explain why you want to do this analysis in vector format? Kind regards, Xander ... View more

Hi Michael, If I understand you correctly you want to setup a cost raster to include speed. Performing a cost distance calculation is not more than a normal distance calculation where the distance is converted to travel cost. It is possible to obtain travel times if the cost raster represents the number of time units per distance unit (inverse speed). Let�??s say you are working with a raster resolution of 100m. For a certain cell "A" the speed is 46 knots. 46 knots is about 23.7 m/s. The cost of that cell shout be 1/23.7 (s/m). When traveling horizontally or vertically over that cell the distance (100m) will be multiplied by the cost (1/23.7), which is results in around 4.2 seconds. So, it will take 4.2 seconds to travel over that cell. For those cells that have a different max speed like 20 knots, the cost raster will have a different (higher) value, since the "costs" is higher to travel over that cell.  20kn * 0.514444 = 10.3m/s. The cost will be 1/10.3 (s/m). Travel over this cell horizontally or vertically will take 100m*1/10.3s/m = 9.7 seconds. After the cost distance calculation you can reclassify your raster in the time zones needed. More info on how cost distance works: http://resources.arcgis.com/en/help/main/10.1/index.html#/How_the_cost_distance_tools_work/009z00000025000000/ Kind regards, Xander ... View more

Hi I have two point layers, one representing river mouths and the other representing beach sites. I also have a water polygon layer. I am trying to calculate the shortest distance from my beach site layer to the nearest river mouth but it has to be through the water layer. The proximity tools wont work as they calculate the shortest distance but in areas where there i have a beach site on one side of a headland and a river mouth on the other it will take the path across land but i need it to go through the water. I also can't use the outline of the coast as a network along which to travel as in areas like the Gulf, the shortest distance will be straight across not via the coastline. Any suggestions? Thanks Hi TJ, I guess you can do this analysis in raster by using Cost Distance (Spatial Analyst): http://resources.arcgis.com/en/help/main/10.2/index.html#//009z00000018000000 ... and you'll find more info here on how it works: http://resources.arcgis.com/en/help/main/10.2/index.html#//009z000000z5000000 In the description it states: If areas with a value of zero represent areas that should be excluded from the  analysis, these values should be turned to NoData before running Cost Distance, by first running the Set  Null tool. By using a cost raster you can define those "dry" areas as Null (NoData). The Cost Analysis will interpret this as areas that cannot be crossed. Specify your river areas as 1 in the same raster and the result of the cost distance will be a raster defining the distance from your sources. Kind regards, Xander ... View more

I have several .xyz files I am trying to import to a feature class.  When I use the ASCII 3D to Feature Class tool the output feature class is empty.  The input file definitely has data in it. Hi Len, If you look at the online help there is an example of the format you can use for the tool: http://resources.arcgis.com/en/help/main/10.2/index.html#//00q900000041000000 If you attach a file you're trying to convert (or a small part of a file) we can have a look at what might be wrong. Please write the settings you have used to import the data too, especially: - input file format (XYZ, XYZI or GENERATE) - output feature class type (MULTPOINT, POINT, POLYLINE or POLYGON) - decimal separator (DECIMAL_POINT or DECIMAL_COMMA) Kind regards, Xander ... View more

How we calculate the area between  contour lines? Hi Satyendra, One way could be using the contour lines to create polygons, but that will likely be very time consuming (if it even works). For this you could use the Feature to Polygon tool which is available with ArcGIS for Desktop Advanced: http://resources.arcgis.com/en/help/main/10.2/index.html#//00170000003n000000 A better way would be to reclassify the DEM (assuming you have one to begin with) using a classification that corresponds to your contour lines: http://resources.arcgis.com/en/help/main/10.2/index.html#/Reclassify/009z000000sr000000/ The resulting raster will be an integer raster. You can open the attribute table and multiply the number of pixels with the pixel size. This will give you the area for a class (area between two contour lines). If you are looking for the area of each separated area try the Region Group tool: http://resources.arcgis.com/en/help/main/10.2/index.html#//009z00000039000000 Kind regards, Xander ... View more

[ATTACH=CONFIG]27251[/ATTACH][ATTACH=CONFIG]27252[/ATTACH][ATTACH=CONFIG]27253[/ATTACH] Hi, i got the footprint,lidar data and aerial photo which i need to use for constructing urban 3d model. i saw some tutorials online, but there is one problem for me. i can open lidar dataset in arcmap (as showd in picture 1 - ground lidar dataset), there are many points in 2d. but when i open it in arcscene 10.1, first several seconds there is a just a box (picture 2), after that nothing shows in the arcscene. but i saw online tutorial, they all can open las dataset in acrscene like cloudy points. Hi Yang, Maybe the amount of data causes this effect. You could try to reduce the amount of data to be displayed by using the "Area of Interest tool" in ArcScene. More info here: http://resources.arcgis.com/en/help/main/10.1/index.html#//00q800000144000000 Kind regards, Xander ... View more

Hello there, I'm trying to convert from raster to vector using the raster to polygon tool but I keep getting an error (000864). It says that the input is not in the defined domain and I'm not sure what that means. Do I have to do another conversion before this one? thank you, im extremely new to arcmap. Hi Carla, As Milan indicates you should have a look at the error description, which you can access through the Menu "Geoprocessing", option "Results". This will open the Results Window which lists the Geoprocessing tools and any errors that may have occurred. Expand the tool that generated the error and below expand the "Messages". See an example below: [ATTACH=CONFIG]27293[/ATTACH] This will reveal the error and provides a link to the Help on that error. In your case (in 10.2) 000864 will point to: http://resources.arcgis.com/en/help/main/10.2/index.html#//00vp00000012000864 000864 : <value>: The input is not within the defined domain. <value>. Description The specified input is not valid for the parameter. You might have tried to use a value for the parameter that is not one of the defined options or is not a valid type or perhaps made a typing error. The command syntax will identify the valid options for each function. For example, the options for the Filter type parameter are only LOW or HIGH. No other text string will be accepted. Solution Check the syntax and documentation to make sure you are specifying the command correctly and that the input types are valid. In order to help you, we will need to know what data you used for this tool. Kind regards, Xander ... View more

Hola a todos, no se si alguien me podria dar una ayuda, tengo un archivo en formato .mxd, y la verdad quiero graficarl en 3D Polyline, y me duele la cabeza buscando de que manera, es una area de un parque nacional, que me gustaria proyectalo en Espacio 3D para asi oder apreciar mucho mas todas sus caracteristicas que posee dicha area, tanto altura, profundidades, caminos, rios, pendientes y demas detalles que me son utiles pa asi monitorear mejor. Por favor denme una ayuda pa lograrlo. Muchas gracias, se lo agradecere de corazon. FYI; included link to Spanish Forum and some introductory topics in Spanish in answer below. Hola DanielAlexandar, Te recomendaría que colocas tu pregunta en el foro en Español. Lo encuentras aquí: http://forums.arcgis.com/forums/50-Espa%C3%B1ol Para contestar tu pregunta un poco; el archivo.mxd es un documento de ArcMap. Normalmente contiene referencias a capas de datos (layers) y su forma de visualización. Lo que entiendo de tu pregunta, es que quieres visualizarla en 3D. Para este fin ArcGIS tiene las aplicaciones ArcScene y ArcGlobe (que requieren la extensión 3D Analyst). Para conseguir más información te recomiendo comenzar por un recorrido rápido por ArcMap: http://help.arcgis.com/es/arcgisdesktop/10.0/help/index.html#/na/006600000332000000/ .. y luego leer el tutorial de ArcGIS 3D Analyst: http://help.arcgis.com/es/arcgisdesktop/10.0/help/index.html#//00q800000093000000 Cordialmente, Xander ... View more

Hello, I'm tryng to populate a field with this VBA code but it doesn't work. I really appreciate any help you can provide. Dim codigo as string If [CAMPO]="Captura" OR [CAMPO]="Replanteo" OR [CAMPO]="GPS" Then        codigo = "1"     ElseIf [CAMPO]="Plano" OR [CAMPO]="Ortofoto" Then         codigo = "2"     ElseIf [CAMPO]="Catastro" OR [CAMPO]="Ajuste parcelario" Then         codigo = "3"     Else codigo = [CAMPO] EndIf __esri_field_calculator_splitter__ codigo Hi alaska@pozo, The only thing I see in your code it the "Else codigo = [CAMPO]" being on 1 line, but changing it doesn't solve the problem. What you can do is change your code and use a Select Case. This simplifies the code and seems to work (at least for me in 10.2): Select Case [CAMPO] Case "Captura", "Replanteo", "GPS"   codigo = "1" Case "Plano", "Ortofoto"   codigo = "2" Case "Catastro","Ajuste parcelario"   codigo = "3" Case Else   codigo = [CAMPO] End Select __esri_field_calculator_splitter__ codigo Hope this works for you too. Kind regards, Xander BTW: since this is the Python forum, you could consider using the Python syntax: def ClfyCampo(campo):     if campo == "Captura" or campo == "Replanteo" or campo == "GPS":         return "1"     elif campo == "Plano" or campo == "Ortofoto":         return "2"     elif campo == "Catastro" or campo == "Ajuste parcelario":         return "3"     else:         return campo __esri_field_calculator_splitter__ ClfyCampo( !CAMPO! ) ... View more

Good morning, I am not sure if this is possible, and I am still fairly new at 3D Analyst. I am wondering if there is a way to convert a 3D shapefile into a TIN so that an image can be draped over it? Or if there is a simpler way to do this? Thanks for your time! Hi Maddy, In case your data consists of points and/or lines, it is better to create a TIN from it. The following links provide some help on that topic: http://resources.arcgis.com/en/help/main/10.2/index.html#//006000000010000000 http://resources.arcgis.com/en/help/main/10.2/index.html#/Create_TIN/00q90000001v000000/ If you have 3D polygons (Polygon Z) you could use it as the floating layer and drape the other layer on top of it. Some explanation of that can be found in the following help topics: http://resources.arcgis.com/en/help/main/10.2/#/Defining_data_as_a_draped_layer_in_ArcScene/00q8000000t5000000/ http://resources.arcgis.com/en/help/main/10.2/index.html#/Understanding_feature_based_heights_in_3D/00q80000013v000000/ http://resources.arcgis.com/en/help/main/10.2/index.html#//00q8000000zp000000 Since you say you're fairly new to 3D Analyst, it may be a good idea to follow an introductory course on the topic. Here you find a list of training provided by Esri: http://training.esri.com/gateway/index.cfm?fa=search.results&searchterm=&search=Search&orderby=&softwareid=20000 Kind regards, Xander ... View more