Problem 464. Function Sniffer

Created by AMITAVA BISWAS

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74 Solutions
24 Solvers

Last Solution submitted on Sep 30, 2020

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Richard Zapor on 1 Jun 2012

The test suite is a little soft. I feel the addition of 'for i=log2(2):abs(n^2-n)', which should yield 'for log2' would stymie almost all the solutions provided.

Richard Zapor on 1 Jun 2012

In my opinion, the Cody problems should expand Matlab understanding not cause frustration in search of obscure functions. To this end, I think the tags should include regexp, symvar, cellfun, sprintf, exist, unique, and cell2mat. Learning the usage of these functions is one purpose of Cody.

Jan Orwat on 13 Jun 2014

also operands like +,-,/,*,.*,~,|,& etc. are treated by Matlab as builtin functions, so in my opinion test case 2 answer sholud be ': sqrt sum' and for test case 3 '- ones rand round'

Rafael S.T. Vieira on 30 Sep 2020 at 16:20

Imho, operators (+,-,&,etc) are a special kind of function in which parameters are arranged in a certain order. The problem does not need to cover them. And again imho, for and if should not even be considered functions, but structures of repetition and control respectively, because they are built-in hardware (and it's how computers work). Moreover they are not mapping values from a set into another as in Math. Finally "functions" that have no output value should be called procedures (such as reset, delete, and disp).

PS: Some operators, these special functions, are also built-in hardware.

Solution Comments

Solution 1532016

2 Comments

2 Comments

J. S. Kowontan on 17 May 2018

Nice...unfortunately, it is not a general solution. For example: if 'x = ones(round(7.7)) - rand + b;', then this code will sniff y = 'b ones rand'.

bainhome on 17 May 2018

you found it huh?:) no,it's not a general solution, I built it base on test suite.

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Problem 464. Function Sniffer

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