i'm New at Arc GIS, i build a full network (Roads and Facilities), and need to get the required results, the problem here that i'm not sure about the right sequence and the best commands to use, i need some one to contact with me online and tell me, or to do the run and get the results
(Create/obtain the GIS feature classes of the required datasets. The origins feature class can be created
using GIS geoprocessing tools to generate a square mesh of a given size (e.g. 50 m × 50 m) over the
city map (polygon feature class), together with its associated centroids. The centroids form the origins
2. For the origins feature class, use GIS geoprocessing tools to evaluate the straight-line distance from
each origin to the closest arc of the pedestrian network (snapping distance) and store this distance in
the origins feature class associated table. Manually delete from the origins feature class all the
centroids (and associated polygons) with distances greater than a certain value, larger than the mesh
size. This is necessary to avoid imprecisions due to excessive origin-to-network snapping distance,
which is not considered in GIS network analysis. It also has the effect of visually clearing up the map
from zones without nearby pedestrian infrastructure. These are usually zones without buildings or
green space parcels of land.
3. For the pedestrian network feature class, add columns to its associated table containing, for each arc,
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the product (K) of impedance × performance value in the From-To and To-From directions, i.e. KFT =
IFT × P and KTF = ITF × P. These K values can be obtained using GIS scripting tools (ArcGIS: field
calculator tool, which uses Python or VBA as scripting languages). If the network is undirected, that is
to say, if the From-To and To-From directions lead to the same impedance, one such value suffices.
4. For each origin i and each destination type j, use GIS network analysis tools (ArcGIS: closest facility)
to find the shortest-impedance path from the origin to the closest facility of type j and set K as
accumulation variable in the calculations (an accumulation variable is a quantity in the network
feature class associated table, whose value is stored cumulatively, in tandem with impedance, as the
shortest-impedance path is derived). Use a facility search tolerance distance similar to the one used for
removing origins in step 2 (the facility search tolerance is the maximum allowed snapping distance
between that facility and the pedestrian network). Repeat this procedure for each destination type j
and store the cumulative value Kij in the associated table of the origins feature class, as well as the
shortest-impedance path cumulative impedance value (Sij). The Kij mean ‘cumulative performancepondered impedance from origin i to the closest facility of type j’. In the end, the origins feature class
associated table will have 2N extra columns, one containing Kij and the other Sij.
5. For each destination type, add one column to the origins feature class associated table (total of N extra
columns) and use GIS scripting tools to fill it with the quotient �"#$ = Kij / Sij. This quotient is the
impedance-averaged pedestrian network performance in going from i to j.
6. In the origins feature class add one column and use GIS scripting tools to fill it with
WFi = Σj ωj �"#$ / Σj ωj. This quantity is the WF index for centroid i and is the final outcome of the
calculations. It has the interpretation of ‘impedance-averaged pedestrian network performance in
going from origin i to the closest facilities of all types, weighted by facility importance’. Note that the
WF index is not a performance indicator per se; rather, it reflects average performance scores, in the
7. Use GIS join tools to associate the WFi values to the corresponding i in the mesh polygon feature
class. Represent the polygon feature class joined values in the city map in colour-code or greyscale.)
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Hi I am GIS and Remote Sensing professional looking forward to work with you on step by step guide of GIS modeling project. I think we can start as soon as coming Monday. Thank you
I am a student of university of Sri Jayewardhenepura. Already I followed Arcgis and also Qgis software. As a helper I'll support you to do their task.