mike-sul/scalc

Sets Calculator

Sets Calculator

Install

1. Install golang

sudo apt-get update
sudo apt-get install -y golang-go

2. Configure golang

export GOPATH=~/go
export PATH=$GOPATH/bin:$PATH

3. Install scalc

go get -u github.com/mike-sul/scalc/cmd/scalc

Test

cd $GOPATH/src/github.com/mike-sul/scalc/test
go test -v
scalc [ SUM [ DIF a.txt b.txt c.txt ] [ INT b.txt c.txt ] ]

Run

scalc <expression>

expression := “[“ operator set_1 set_2 set_3 … set_n “]”
operator := “SUM” | “INT” | “DIF”
set := file | expression

Example

scalc [ SUM [ DIF a.txt b.txt c.txt ] [ INT b.txt c.txt ] ]

Files contains sorted integers, one integer in a line. At least one set should be given to each operator. Operator: SUM - returns union of all sets INT - returns intersection of all sets DIF - returns difference of first set and the rest ones

$ cat a.txt
1
2
3

$ cat b.txt
2
3
4

$ cat c.txt
3
4
5

scalc [ SUM [ DIF a.txt b.txt c.txt ] [ INT b.txt c.txt ] ]
1
3
4

Racket lang alternative

Racket lang has built in support of sets and sets arithmetic, see here https://docs.racket-lang.org/reference/sets.html#%28def._%28%28lib._racket%2Fset..rkt%29._set-union%29%29

Install

sudo add-apt-repository ppa:plt/racket -y
sudo apt-get update -y
sudo apt-get install racket -y

Run

mike@msul:~/work/private/go/src/github.com/mike-sul/scalc/test$ racket 
Welcome to Racket v7.4.
> [ sort [ set-union [ set-subtract [ file->list "a.txt" ] [file->list "b.txt"] [file->list "c.txt"] ] [ set-intersect [ file->list "b.txt"] [ file->list "c.txt" ] ] ] < ]
'(1 3 4)
>