I have a dataset (in excel) of species with the coordinates in which they were sighted, collected by many different people over decades. Aside from coordinates, the dataset also specifies a datum (Nad_27, Nad_83, WGS_84). I added the data to ArcGIS.
So my fields look like:
The HorizontalDatum column is confusing me. This one excel file says the dataset is composed of 3 different datums depending on the record. Although the original datum is said to be one of those three for any given record, can I set the datum for the entire dataset to Nad_83 in arcGIS and ignore this column? Will that still be accurate? I don't understand datums or transformations enough to be sure.
If not, will I have to split the dataset into 3 shapefiles for records of each datum?
These data points are all within the same province. I just want to keep all the records in the same shapefile.
To summarize and clarify: I will need to set a geographic coordinate system for this shapefile manually, as it's coming from excel data. Can I set the entire shapefile to Nad_83, or should I split it up into 3 shapefiles, and project those with the 3 "Horizontal Datums" stated in the excel field? This would be less than ideal... I'd like to be able to query the whole dataset in one go.
أكثر...
So my fields look like:
The HorizontalDatum column is confusing me. This one excel file says the dataset is composed of 3 different datums depending on the record. Although the original datum is said to be one of those three for any given record, can I set the datum for the entire dataset to Nad_83 in arcGIS and ignore this column? Will that still be accurate? I don't understand datums or transformations enough to be sure.
If not, will I have to split the dataset into 3 shapefiles for records of each datum?
These data points are all within the same province. I just want to keep all the records in the same shapefile.
To summarize and clarify: I will need to set a geographic coordinate system for this shapefile manually, as it's coming from excel data. Can I set the entire shapefile to Nad_83, or should I split it up into 3 shapefiles, and project those with the 3 "Horizontal Datums" stated in the excel field? This would be less than ideal... I'd like to be able to query the whole dataset in one go.
أكثر...