[erlang-questions] Newbie Question about io:format
Tue Feb 21 10:42:14 CET 2017
Because Erlang has no functions with variable amount of arguments (like for
example in printf C/C++), args to io:format are passed as a list. So
correct way to call it is:
io:format("Bla ~p~n", [Av1]).
Where ~p is to print any value, also there are more ways to format a value,
consult the documentation page at http://erlang.org/doc/man/io.html#fwrite-1
2017-02-21 10:15 GMT+01:00 Hakim Fajardo <>:
> First, thank you because this is a great resource.
> Second, I started writing basic programs every day to improve my Erlang
> coding. I wrote a simple program that calculates the average of a list of
> numbers. But I keep getting this error about io:format.
> prices() ->
> io:format("List is empty ~n");
> %% determine number of items in the list to calculate average%%
> prices(L) when is_list(L) ->
> Size = length(L),
> Sum1 = lists:sum(L),
> Av1 = Sum1 / Size,
> io:format("The average equals ~n", Av1).
> Eshell V8.2 (abort with ^G)
> 1> L = [1,2,2,2,3,3,4].
> 2> c(standev).
> 3> standev:prices(L).
> ** exception error: bad argument
> in function io:format/3
> called as io:format(<0.50.0>,"The average equals
> Why am I getting '**exception error:'?
> Thank you, I hope this isn't too newbie a question.
> erlang-questions mailing list
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the erlang-questions