mdsumner

obably have to think through some books I've read over the years, but right now it's dominated by R. I used to read a fair bit about object-oriented stuff, and now trying to learn C++ I realize how much I've learnt from R over the last 8-10 years. I love John Chamber's "Programming with Data", but I haven't read his newer one and that's probably a better read now. 

I would like to have a wiki-thing that we could dump these lists on and then re-edit prioritize etc. I have some notes I send people for R below. 

My current reading list is 

"The C++ Programming Language", by Bjarne Stroustrup (go for Ed. 4 which is up to date for C++11).

http://alignedleft.com/work/d3-book

mdsumner

A recreation of http://gis.stackexchange.com/questions/152094/heatmap-on-globe-distortion-problems

```{r}
library(raster)
library(geosphere)
library(MASS)

r <- raster(extent(-180, 180, -90, 90), nrow = 256, ncol = 256)

mdsumner

library(webp)
library(png)
library(curl)
u <- "http://oceancolor.gsfc.nasa.gov/cgi/l3/V20160202016022.L3m_R3QL_NPP_CHL_chlor_a_9km.nc.png?sub=img"
f <- gsub("\\?sub=img", "", basename(u))
curl_download(u, f)
bm <- readPNG(f)

newfile <- gsub("png", "webp", f)
write_webp(bm, newfile)

mdsumner

## My answer to https://stat.ethz.ch/pipermail/r-sig-geo/2016-January/023953.html


library(raster)

## for example
#r <- getData('SRTM', lon=147, lat=-42)
# or 
r <- raster("C:/temp/srtm_66_21.tif")

mdsumner

## wtf
#' Combine a list of PolygonDataFrame objects into a single object. 
#' 
#' Objects are combined by modifying sequential IDs to increase. 
c_poly <- function(x) {
  poly <- x[[1]]
  if (length(x) == 1L) {
    warning("input of length one, returning first element")
    return(poly)
  }

mdsumner

## NOTE: as is this code downloads 3 files, 22Mb in total


 ## files to compare
 files <- c("A2015283.L3m_DAY_CHL_chlor_a_4km.nc", "A2015284.L3m_DAY_CHL_chlor_a_4km.nc", "A2015285.L3m_DAY_CHL_chlor_a_4km.nc")
 baseu <- "http://oceandata.sci.gsfc.nasa.gov/cgi/getfile"
 
 ## download the files
 for (i in seq_along(files)) {
   if (!file.exists(files[i])) {

mdsumner

# centroids
#  still need Inner Centroid

v <- cbind(c(0.3, 0.6, 0.4), c(0.2, 0, 0.8))
tri <- c(1, 2, 3)

# centroid (weight)
cw <- matrix(apply(v[tri, ], 2, mean), ncol = 2)

library(tripack)  

mdsumner

#' Mutate for Spatial
#' 
#' mutate . . .
#' 
#' @export
#' @examples 
#' library(sp)
#' library(maptools)
#' data(wrld_simpl)
#' library(dplyr)

mdsumner

#' Mutate for Spatial
#' 
#' @param .data 
#' @param ... 
#' @param .dots 
#'
#' @rdname spdplyr
#' @export
#' @examples 
#' library(sp)

mdsumner

Problem with tidyr in R 3.2.4, works fine in 3.2.3

library(tidyr); library(dplyr);   

## 
## Attaching package: 'dplyr'