turner_introduction.R
In turner: Turn Vectors and Lists of Vectors into Indexed Structures

## ----load_turner, message=FALSE-----------------------------------------------
# load package turner
library(turner)

## ----data_matrix--------------------------------------------------------------
# create a matrix
set.seed = 21
some_data = round(matrix(rnorm(90), 10, 9), 3)
rownames(some_data) = 1:10
colnames(some_data) = paste("X", 1:9, sep='')

# take a peek
head(some_data, n=5)

## ----blocks-------------------------------------------------------------------
# list of blocks
blocks = list(B1 = 1:3, B2 = 4:5, B3 = 6:9)
blocks

## ----indexify-----------------------------------------------------------------
# get indices of blocks
indices = indexify(blocks)
indices

## ----list_to_dummy------------------------------------------------------------
# get dummy matrix based on blocks
dummy = list_to_dummy(blocks)
dummy

## ----from_to------------------------------------------------------------------
# get starting and ending positions
start_end = from_to(blocks)
start_end

# vectors from and to
from = start_end$from
to = start_end$to

## ----extract_first_block------------------------------------------------------
# extract first block
some_data[,from[1]:to[1]]

## ----get_first_block----------------------------------------------------------
# get first block
some_data[,blocks[[1]]]

## ----str_list-----------------------------------------------------------------
# string list
str_list = list(c("a","b","c"), c("d", "e"), c("f","g","h","i"))

## ----failed_extraction, eval=FALSE--------------------------------------------
#  # failed attempt
#  some_data[,str_list[[1]]]

## ----success_extraction-------------------------------------------------------
# start-end position for 'str_list'
fromto_aux = from_to(str_list)
from1 = fromto_aux$from
to1 = fromto_aux$to

# successful attempt
some_data[,from1[1]:to1[1]]

## ----lenghts------------------------------------------------------------------
# say you have some list
some_list = list(1:3, 4:5, 6:9)

# length of each vector (vector output)
lengths(some_list, out='vector')

# length of each vector (list output)
lengths(some_list, out='list')

## ----length-------------------------------------------------------------------
# compared to 'length()'
length(some_list)

## ----funlist------------------------------------------------------------------
# sum of all elements in 'some_list'
funlist(some_list, sum)

# maixmum of all elements in 'some_list'
funlist(some_list, max)

# product of all elements in 'some_list'
funlist(some_list, prod)

# mean value of all elements in 'some_list'
funlist(some_list, mean)

## ----listsize-----------------------------------------------------------------
# number of elements in 'some_list'
listsize(some_list)

## ----listify------------------------------------------------------------------
# vector of indices
number_elements = c(3, 1, 5)

# list of index vectors based on 'number_elements'
listify(number_elements)