How to sum a bash array of numbers (some in scientific notation)?

Question

Since the following command using bc does not work for numbers in scientific notation, I was wondering about an alternative, e.g. using awk?

sum=$( IFS="+"; bc <<< "${arrValues[*]}" )

Stéphane Chazelas · Accepted Answer · 2013-11-06 16:31:09Z

up vote 1 down vote accepted

sum=$(
  awk 'BEGIN {t=0; for (i in ARGV) t+=ARGV[i]; print t}' "${arrValues[@]}"
)

With zsh (in case you don't have to use bash), since it supports floating point numbers internally:

sum=$((${(j[+])arrValues}))

With ksh93:

If you need the kind of precision that bc provides, you could pre-process the numbers so that 12e23 is changed to (12*10^23):

sum=$(
  IFS=+
  sed 's/\([0-9.]*\)[eE]\([-+]*[0-9]*\)/(\1*10^\2)/g' <<< "${arrValues[*]}" |
    bc -l
)

answered Nov 6 '13 at 16:03

Stéphane Chazelas
88.7k12100215

@MaVe, the + character is not special to the shell and doesn't need quoted (quoting won't harm though). – Stéphane Chazelas Nov 6 '13 at 22:26

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choroba · Answer 2 · 2013-11-06 16:07:02Z

up vote 1 down vote

Perl solution:

perl -MList::Util=sum -l -e 'print sum(@ARGV)' "${array[@]}"

answered Nov 6 '13 at 16:07

choroba
5,288717

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