Difference between revisions of "Technical Notes"
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Aubrey Moore (Talk | contribs) (→R scripts) |
Aubrey Moore (Talk | contribs) (→R scripts) |
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==R scripts== | ==R scripts== | ||
+ | ===shape2text.r=== | ||
<pre> | <pre> | ||
# this R script reads a shapefile and exports it to a csv text file | # this R script reads a shapefile and exports it to a csv text file | ||
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</pre> | </pre> | ||
+ | ===utm_trap_routes.r=== | ||
<pre> | <pre> | ||
# This script creates a shapefile for each trap route with UTM coordinates. | # This script creates a shapefile for each trap route with UTM coordinates. |
Latest revision as of 16:24, 11 March 2008
SQL
- Query to find trap_id's in the trap_routes table which are unmatched in the trap table:
SELECT trap_routes.trap_id, trap.trap_id FROM trap_routes LEFT JOIN trap ON trap_routes.trap_id = trap.trap_id WHERE trap.trap_ID IS NULL
- Query to update trap table using values from trap_routes table:
UPDATE trap, trap_routes SET trap.trap_route=trap_routes.trap_route, trap.trap_route_sequence=trap_routes.trap_route_sequence WHERE trap.trap_id=trap_routes.trap_id
- Query to add extra column with observation_date format as m/d/Y:
SELECT *,DATE_FORMAT(observation_date,'%m/%d/%Y') AS US_observation_date FROM crb_observations;
R scripts
shape2text.r
# this R script reads a shapefile and exports it to a csv text file library(maptools) x<-readShapePoints(file.choose()) write.csv(x,"temp.csv",row.names=F)
utm_trap_routes.r
# This script creates a shapefile for each trap route with UTM coordinates. # Aubrey Moore 2008.03.12 library(maptools) library(rgdal) library(RODBC) # Establish connection to database; "oryctes" is a DSN channel <- odbcConnect("oryctes") # Get list of trap routes sql_text<-paste( "SELECT trap_route", "FROM trap", "WHERE date_removed=0", #important "GROUP BY trap_route;") result<-sqlQuery(channel,sql_text) for (i in 1:nrow(result)){ current_trap_route<-result$trap_route[i] # Read trap table from MySQL database. # The fields, data_entry_date and date_removed generate the error message: # "Error in fromchar(x) : character string is not in a standard unambiguous format" # so these have been left out of the query. sql_text<-paste( "SELECT ", " trap_id, data_entered_by, date_deployed, latitude, longitude, location_description,", " trap_type, trap_route, sequence, landowner, notes ", "FROM trap ", "WHERE ", " date_removed=0", " AND trap_route='", current_trap_route, "';", sep="" ) traps<-sqlQuery(channel,sql_text) PointsAsFrame <- SpatialPointsDataFrame(cbind(traps$longitude, traps$latitude),traps) # we need to set the projection string attribute to the point set to be transformed. proj4string(PointsAsFrame) <- CRS("+proj=longlat +datum=WGS84") # perform the transformation and plot the points ThePointsUTM <- spTransform(PointsAsFrame,CRS("+proj=utm +zone=55 +datum=WGS84")) # Write to a shapefile filename <- paste("C:/RMaps/guam map/traps/",current_trap_route,sep="") write.pointShape(ThePointsUTM,file=filename,coordinates=ThePointsUTM@coords) } print('FINISHED')