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Methodological Errors
A methodological error I have encountered in this project is when I performed the data analysis in ArcMap to calculate the population density for the GVRD. I thought it is better to do all the data analysis, such as creating and calculating new fields in ArcMap. Then, save the shapefile in ArcMap displaying all the population density values and export this shapefile into Idrisi for further population density analysis. But when I import this shapefile to Idrisi from ArcMap using the SHAPEIDR function, the population density values did not show up in Idrisi. Instead it displayed the ID numbers only, which is not what I really wanted. I then realized that Idrisi doesn't recognize anything other than ID numbers when first importing polygon shapefiles into it. I had to further assign all the population density values to its ID numbers by creating an attribute value file with the edit function to specify all the assign values in order to display the population density map that I wanted in Idrisi.
I have encountered many operational difficulties with
getting the data I wanted to overlay other data properly. Originally
I didn't have to digitize the mellenium skytrain stations myself,
since I manage to find a shapefile with all the skytrain stations
from other sources. I have made sure that all the projections, units,
and data type are the same as all my other data files, but when I
tried to overlay it on top of other layers in Idrisi, nothing showed
up. Until in the end I had creat a new shapefile by digitizing all
the skytrain stations myself in ArcMap and exporting it to Idrisi.
And it worked this time. Therefore, when working with data from other
sources, even though the reference systems or units may be the same
as the data I am working with, there might still be other reasons
that might have prevented me from using it in. |
