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Table of Contents

1 Pep8


  • function and class should be separated by 2 lines
  • In a class, function should be separated by 1 line
  • 1 space before and after variable assignment


  • function, variable, attribute: func_var_attr
  • protected instance attributes: _protected_field
  • private instance attributes: __private_field
  • class and exception: ClassExceptionName
  • module level constants: CONSTANT
  • instance method of class should use self as first parameter, refer to the object
  • class method should use cls as first parameter, refer to the class


use DONT use
a is not b not a is b
if not list if len(list) == 0


  • always use absolute path
  • if must use relative, use from . import foo instead of import foo

1.1 document

One can use one line or multi-line document. The doc string can be retrieved by func.__doc__.

def func():
  """one line doc"""

def func():
  """The outline

  The above empty line is required.
  Here's the detailed documentation.

2 R

  • For vectors, [] returns the element.
  • For lists, [] will return the the element inside a list, while [[]] will return the single element.
  • $ can be used for indexing with character.
  • The empty index [] will returns the entire vector with irrelevant attributes removed. The only retained ones are the names, dim and dimnames attributes.
dim(z) <- c(3,5,100)~

2.0.1 data example

## (HEBI: Command line arguments)
args = commandArgs(trailingOnly=TRUE)
csvfile = args[1]
csv = read.csv(csvfile, header=TRUE)

total_test <- dim(csv)[[1]]
sub = subset(csv, reach_code>=5)
total_reach_poi <- dim(sub)[[1]]
sub = subset(csv, reach_code==5 & status_code == 1)
total_fail_poi <- dim(sub)[[1]]

sub <- sub[1:(length(csv)-2)]
## (HEBI: calling a function)
funcs = TransferFunction(sub);

## (HEBI: define a function)
Constant <- function(data) {
  ## (HEBI: return value as a vector)
  ret <- c()
  i <- 1
  ## (HEBI: a for loop using the vector as range)
  for (i in c(1:length(data))) {
    col = data[i];
    ## (HEBI: Get the name of a column)
    name = names(col);
    if (substr(name, 1, 6) == "output") {
      ## (HEBI: remove of NA)
      newcol = col[!is.na(col)];
      if (length(newcol) > 2) {
        value <- newcol[1]
        ## (HEBI: check the value of the vector is all the same)
        if (length(newcol[newcol != value]) == 0) {
          ## (HEBI: pushing a new value to the return vector)
          ret <- c(ret, paste("name = ",  value))}}}}