Commands tagged bc -l sorted by votes

Commands tagged bc -l (9)

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Define a quick calculator function

defines a handy function for quick calculations from cli. once defined: ? 10*2+3 Show Sample Output
This is sample output - yours may be different.
```
23?
```
58

? () { echo "$*" | bc -l; }

fizz · 2009-06-28 20:15:30 27
Define a quick calculator function

POSIX compliant arithmetic evaluation. = 10*2+3 Show Sample Output
This is sample output - yours may be different.
```
23
```
3

=() { echo $(($*)); }

xlz · 2013-05-03 04:27:07 7
Calculate pi with specific scale

a() function in bc is for arctangent, available if using -l option included. Show Sample Output
This is sample output - yours may be different.
```
3.1415926532
```
1

echo 'scale=10; 4*a(1)' | bc -l

chars19 · 2012-10-08 15:03:07 8
Apply, in parallel, a bc expression to CSV

Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel Show Sample Output
This is sample output - yours may be different.
```
$ paste -d, <(seq 10) <(seq 10 -1 1) | pbc 'sqrt({1}*{2})'
3.16227766016837933199
4.24264068711928514640
4.89897948556635619639
5.29150262212918118100
5.47722557505166113456
5.47722557505166113456
5.29150262212918118100
4.89897948556635619639
4.24264068711928514640
3.16227766016837933199
```
1

pbc () { parallel -C, -k -j100% "echo '$@' | bc -l"; }

eroenj · 2014-06-02 19:08:03 7
small CPU benchmark with PI, bc and time.

# 4 cores with 2500 pi digits CPUBENCH 4 2500 . every core will use 100% cpu and you can see how fast they calculate it. if you do 50000 digitits and more it can take hours or days Show Sample Output
This is sample output - yours may be different.
```
CPUBENCH 3 5000
Cores: 3
Digit: 5000

real	0m18.680s
user	0m18.678s
sys	0m0.005s

real	0m18.901s
user	0m18.869s
sys	0m0.035s

real	0m18.902s
user	0m18.899s
sys	0m0.005s
```
1

CPUBENCH() { local CPU="${1:-1}"; local SCALE="${2:-5000}"; { for LOOP in `seq 1 $CPU`; do { time echo "scale=${SCALE}; 4*a(1)" | bc -l -q | grep -v ^"[0-9]" & } ; done }; echo "Cores: $CPU"; echo "Digit: $SCALE" ;}

emphazer · 2018-05-14 17:30:37 199

Converts the output of disklabel from bytes to Gigabytes on FreeBSD

This was done in csh. Show Sample Output

echo `disklabel mfid1s4 | sed -n '$p' | awk '{print $2}'` / 1024 / 1024 | bc -l

RageJello · 2012-05-04 12:48:58 3

Define a quick calculator function

Same functionality without using bash functions. Show Sample Output
This is sample output - yours may be different.
```
$ ? 3+4/2
5
```
0

alias ?=concalc

boynux · 2014-01-02 01:46:44 9
Shell pocket calculator (pure sh)

This shell calculator uses POSIX features only and is therefore portable. By default the number of significant figures is limited to 8 with trailing zeros stripped, resembling the display of a basic pocket calculator. You might want to increase this to 12 to emulate a scientific calculator. Show Sample Output
This is sample output - yours may be different.
```
$ calc "x = 2 + 2; ++x"
5
$ calc "10 / 16"
0.625
$ calc "sqrt(2)"
1.4142136
$ calc "(1.2 + 3.4) ^ 56"
1.3014832e+37
```
0

calc(){ printf "%.8g\n" $(printf "%s\n" "$*" | bc -l); }

lordtoran · 2019-02-06 23:32:35 607
small CPU benchmark with PI, bc and time.

Broken in two parts, first get the number of cores with cat /proc/cpuinfo |grep proc|wc -l and create a integer sequence with that number (xargs seq), then have GNU parallel loop that many times over the given command. Cheers! Show Sample Output
This is sample output - yours may be different.
```
...
66983895228684783123552658213144957685726243344189303968642624341077\
3226978028073189154411010446823252716201052652272111660396

real	0m31,847s
user	0m59,085s
sys	0m0,151s
```
-2

time cat /proc/cpuinfo |grep proc|wc -l|xargs seq|parallel -N 0 echo "scale=4000\; a$1$\*4" '|' bc -l

kostis · 2018-12-06 05:15:24 674

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Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Show what PID is listening on port 80 on Linux

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

List all symbolic links in a directory matching a string

Finds all symbolic links in the specified directory which match the specified string pattern. I used this when upgrading from an Apple-supported version of Java 6 (1.6.0_65) to an Oracle-supported version (1.7.0_55) on Mac OS X 10.8.5 to find out which executables were pointing to /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands (Apple version) vs. /Library/Java/JavaVirtualMachines/jdk1.7.0_55.jdk/Contents/Home/bin (Oracle version). However, it appears the current JDK installation script already takes care of modifying the links.

The simplest way to transport information over a network

Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.

Generate a list of items from a couple of items lists A and B, getting (B - A ) set

ItemsListtoAvoid (A) could be a list of files with a special characteristic to exclude. It can be a result of previous processing list, ex. a list of files containing a special string. AlItemsList.txt (B) Is a complete list of items including some or all items in A. $Difference is saved in ItemsDifference.txt

Define a quick calculator function

POSIX compliant arithmetic evaluation. = 10*2+3

Extract all of the files on an RPM on a non-RPM *nix

Show a prettified list of nearby wireless APs

Given $PID, print all child processes on stdout

Simpler.

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Commands tagged bc -l (9)

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