csum

Name

csum : Calculate cumulative sum

Synopsis

Usage   : csum [+r] [+<n>h] [key=<key>] val=<val> <file>

Version : Thu May 22 19:59:12 JST 2014

Description

Adds the specified field (val=) from each row of the speficied file (or

standard input) and inserts the cumulative sum of all previous rows as a new

field immediately to the right of the summed field. This is used to

return a cumulative sum.

Example 1

Calculates the cumulative total inventory delivered for each store.

(Summs the value in the 4th field and inserts the result in the

5th field.)

(Original Data:data) Store_Name Date Qty Sold Qty_Stocked

$ cat data

Store_A Day_1 103 62

Store_A Day_2 157 94

Store_A Day_3 62 30

Store_A Day_4 131 84

Store_A Day_5 189 111

Store_A Day_6 350 20

Store_A Day_7 412 301

$ csum val=4 data

Store_A Day_1 103 62 62

Store_A Day_2 157 94 156

Store_A Day_3 62 30 186

Store_A Day_4 131 84 270

Store_A Day_5 189 111 381

Store_A Day_6 350 20 401

Store_A Day_7 412 301 702

                      ↑Cumulative sum of field 4 in each record (Cumulative Sum)

Example 2

If you want to reset the cumulative sum when the value of a particular

field changes, speficiy the reset trigger field as "key=".

Calculates the cumulative total inventory delivered for each store.

(Reset the cumulative sum whenever the value of the 1st field changes.)

(Original Data:data) Store_Name Date Qty Sold Qty_Stocked

$ cat data

Store_A Day_1 103 62

Store_A Day_2 157 94

Store_A Day_3 62 30

Store_A Day_4 131 84

Store_B Day_1 210 113

Store_B Day_2 237 121

Store_B Day_3 150 82

Store_B Day_4 198 105

Store_C Day_1 81 52

Store_C Day_2 76 49

Store_C Day_3 38 21

Store_C Day_4 81 48

$ csum key=1 val=4 data

Store_A Day_1 103 62 62

Store_A Day_2 157 94 156

Store_A Day_3 62 30 186

Store_A Day_4 131 84 270

Store_B Day_1 210 113 113  <- Reset the sum

Store_B Day_2 237 121 234

Store_B Day_3 150 82 316

Store_B Day_4 198 105 421

Store_C Day_1 81 52 52     <- Reset the sum

Store_C Day_2 76 49 101

Store_C Day_3 38 21 122

Store_C Day_4 81 48 170

Example 3

If you want to replace the target field with the cumulative sum,

use the "+r" option.

Replace the Qty_Stocked with the Cumulative Qty Stocked.

(Cumulative sum the 4th field and output result to the

4th field.)

(Original Data:data) Store_Name Date Qty Sold Qty_Stocked

$ cat data

Store_A Day_1 103 62

Store_A Day_2 157 94

Store_A Day_3 62 30

Store_A Day_4 131 84

Store_A Day_5 189 111

Store_A Day_6 350 20

Store_A Day_7 412 301

$ csum +r val=4 data

Store_A Day_1 103 62

Store_A Day_2 157 156

Store_A Day_3 62 186

Store_A Day_4 131 270

Store_A Day_5 189 381

Store_A Day_6 350 401

Store_A Day_7 412 702

                  ↑Replace with the cumulative sum

Example 4

The "+<n>h" option will skip the first <n> records in the file. This is useful

when the first line is a header line. The header for the cumulative total

field that is inserted is "@".

(Original Data:data)

$ cat data

Store_Name Date Qty Sold Qty_Stocked  <- Header Line

Store_A Day_1 103 62

Store_A Day_2 157 94

Store_A Day_3 62 30

Store_A Day_4 131 84

Store_A Day_5 189 111

Store_A Day_6 350 20

Store_A Day_7 412 301

$ csum +h val=4 data

Store_Name Date Qty Sold @ Qty_Stocked       <- "@" is inserted at added field

Store_A Day_1 103 62 62

Store_A Day_2 157 94 156

Store_A Day_3 62 30 186

Store_A Day_4 131 84 270

Store_A Day_5 189 111 381

Store_A Day_6 350 20 401

Store_A Day_7 412 301 702

$ csum +r +h val=4 data

Store_Name Date Qty @ Qty_Stocked            <- "Sold" is replaced by "@"

Store_Name Date Qty @ Qty_Stocked           <- "Sold" is replaced by "@"

Store_A Day_1 103 62

Store_A Day_2 157 156

Store_A Day_3 62 186

Store_A Day_4 131 270

Store_A Day_5 189 381

Store_A Day_6 350 401

Store_A Day_7 412 702

Example 5

If the data has decimals, the result is displayed with precision

equal to the most precise value summed.

$ cat data

A 1

A 1.2

A 1.23

B 2

B 2.34

B 3

$ csum key=1 val=2 data

A 1 1

A 1.2 2.2

A 1.23 3.43

B 2 2

B 2.34 4.34

B 3 7.34

Example 6

val=<pos> can be specified as an exact value, a range (/), multiple

non-consecutive values (@) or relative to the last field (NF NF-<n>).

$ csum val=1 data

$ csum val=2/4 data <-- Sums all fields from the 2nd to the 4th and

inserts the cumulative sum to the right of

each field.

$ csum val=2@4 data <-- Sums the 2nd and 4th fields, and

inserts the cumulative sum to the right of

each field.

$ csum val=NF data  <-- You can also specify the last field (NF)

$ csum val=NF-2 data

$ cat data

A 1 2

A 3 4

A 5 6

$ csum val=2/3 data

A 1 1 2 2

A 3 4 4 6

A 5 9 6 12

(Note)

The old syntax is csum [ref=<ref>] key=<key> <file>

This old syntax will be supported for the near future.