Revfad Blog

Tag: geography

  • A hole in Los Altos (continued)

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    David Faden
    in

    The city clerk got back to me this morning. (Thanks much for the prompt response!) The hole in the map is also a hole in the ground — a reservoir belonging to the City of Mountain View. We happened to be in the area after checking out Tom’s Depot Cafe yesterday so I snapped a…

  • A hole in Los Altos

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    by

    David Faden
    in ,

    Looking at the Census page for Los Altos, something funny caught my eye: there’s a hole in the map for Los Altos: https://data.census.gov/profile/Los_Altos_city,_California?g=160XX00US0643280 Returning to the data from https://lab.data.ca.gov/dataset/california-city-boundaries-and-identifiers, we see the same thing: > library(ggplot2)> library(sf)> cities <- read_sf(“~/Downloads/California_Cities_and_Identifiers_Blue_Version_view_-6943741225906831761.gpkg”)> losAltos <- subset(cities, CDTFA_CITY == “Los Altos”)> ggplot(losAltos) + geom_sf() What’s in that hole? >…

  • What Wittier Whittier

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    David Faden
    in

    I was really impressed to get an almost immediate reply from the CIO, GIS to my note about Whittier appearing to some extra stuff in the geometries provided here: https://lab.data.ca.gov/dataset/california-city-boundaries-and-identifiers. They pointed to the California Department of Tax and Fee Administration as the original source of the geometries, which has been updated in the meantime:…

  • California cities (continued)

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    by

    David Faden
    in

    Let’s get back roughly to where we were with the R session from California cities, reading in a copy of the data pulled from Wikipedia. > library(dplyr)> library(fillpattern)> library(sf)> library(ggplot2)> cities <- read_sf(“~/Downloads/California_Cities_and_Identifiers_Blue_Version_view_-6943741225906831761.gpkg”)> stats <- read.csv(url(“https://raw.githubusercontent.com/fadend/ca_cities_data/refs/heads/main/ca_cities.csv”), stringsAsFactors=FALSE) Oops. There’s some disagreement on names: > setdiff(stats$city_name, cities$city_name)[1] “Angels Camp” “California City” “City of Industry”> setdiff(cities$city_name, stats$city_name)[1]…

  • California cities

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    by

    David Faden
    in

    Here’s something fun: boundaries for cities in California: https://lab.data.ca.gov/dataset/california-city-boundaries-and-identifiers. Working with this in R: > library(sf)> cities <- read_sf(“~/Downloads/California_Cities_and_Identifiers_Blue_Version_view_-6943741225906831761.gpkg”) There are a few columns with the city names; “CENSUS_PLACE_NAME” and “CDTFA_CITY” (CA Department of Tax and Fee Administration?) agree so let’s just use “CDTFA_CITY” > sum(cities$CENSUS_PLACE_NAME != cities$CDTFA_CITY)[1] 0 It’s nice to see that there…