Bii o ṣe le Lo GNU bc (Ẹrọ iṣiro Ipilẹ) ni Lainos

bc (Ẹrọ iṣiro Ipilẹ) jẹ iwulo laini aṣẹ ti o funni ni ohun gbogbo ti o nireti lati imọ-ẹrọ ti o rọrun tabi ẹrọ iṣiro owo. O jẹ ede ti o ṣe atilẹyin awọn nọmba titọ lainidii pẹlu ipaniyan ibaraenisọrọ ti awọn alaye ati pe o ni iṣọpọ iru si ti ede siseto C.

O le ṣee lo ni igbagbogbo bi boya ede afọwọkọ mathematiki tabi bi ikarahun mathematiki ibanisọrọ bi a ti ṣalaye ninu nkan yii.

Ti o ko ba ni bc lori eto rẹ, o le fi sii nipa lilo oluṣakoso package fun pinpin rẹ bi o ti han:

$ sudo apt install bc	#Debian/Ubuntu
$ sudo yum install bc	#RHEL/CentOS
$ sudo dnf install bc	#Fedora 22+

Lati ṣii bc ni ipo ibaraenisọrọ, tẹ aṣẹ bc lori aṣẹ aṣẹ ati bẹrẹ ni ibere ṣe iṣiro awọn ifihan rẹ.

$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 

10 + 5
15

1000 / 5
200

(2 + 4) * 2
12

O yẹ ki o ṣe akiyesi pe lakoko ti bc le ṣiṣẹ pẹlu aiṣedeede lainidii, o ṣe deede awọn aiyipada si awọn nọmba odo lẹhin aaye eleemewa, fun apẹẹrẹ ikosile 3/5 awọn abajade si 0 bi o ṣe han ninu abajade atẹle.

$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 

3 / 5
0

O le lo Flag -l lati ṣeto iwọn aiyipada (awọn nọmba lẹhin ti nomba eleemewa) si 20 ati ṣafihan asọye iwe-ikawe iṣiro deede bakanna. Bayi ṣiṣe iṣaju iṣaaju lẹẹkan si.

$ bc -l
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 

3 / 5
.60000000000000000000

5 / 7
.71428571428571428571

Ni omiiran, o le ṣọkasi iwọn lẹhin ṣiṣi bc bi o ti han.

$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 

scale=0; 8%5
3

scale=1; 8%5
0

scale=20; 8%5
0

scale=20; 8%11
.00000000000000000008

O tun le lo aṣẹ atẹle fun awọn ẹja ti o wọpọ fun apẹẹrẹ ni bash, ksh, csh, lati ṣe awọn ariyanjiyan si bc bi o ti han.

$ bc -l <<< "2*6/5"

2.40000000000000000000

Jẹ ki a wo bi a ṣe le lo bc ti kii ṣe ibaraenisọrọ, eyi tun wulo fun awọn idi afọwọkọ ikarahun.

$ echo '4/2' | bc
$ echo 'scale=3; 5/4' | bc
$ ans=$(echo "scale=3; 4 * 5/2;" | bc)
$ echo $ans

Lati ṣe ilana gangan ede POSIX bc, lo asia -s ati lati jẹki awọn ikilo fun awọn amugbooro si POSIX bc, lo aṣayan -w bi o ti han.

$ bc -s
$ bc -w

Fun alaye diẹ sii, wo oju-iwe eniyan bc.

$ man bc

Iyẹn ni gbogbo fun bayi! bc (Ẹrọ iṣiro Ipilẹ) jẹ iwulo laini aṣẹ ti o funni ni ohun gbogbo ti o nireti lati imọ-ẹrọ ti o rọrun tabi ẹrọ iṣiro owo. Ti o ba ni ibeere eyikeyi, de ọdọ wa nipasẹ apakan awọn ọrọ ni isalẹ.