sum_list(+List, ?Sum)

Determine the sum of all numbers in a list (first parameter), the sum is unified with the second parameter.

This predicate is located in the file 'list.txt', use ensure_loaded/1 to include this file.

see also: conc/3 del/3 largest_number/2 last/2 lengthlist/2 member/2 prefix/2 reverse/2 smallest_number/2 sublist/2 suffix/2 sum_list_integer/2

Example
sum_list([], S). succeeds and the variable S is unified with the value 0
S=0
sum_list([1, 2.4, 3], S). succeeds and S is unified with the value 6.4
S=6.4
sum_list([1, 2], 3.1). fails because 3 is the sum of the list and that value cannot be unified with the value 3.1

 

 

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