In a file namedsubtract.m, create a function that calculates a second return value,absdif, only if requested.

typesubtract.m

function [dif,absdif] = subtract(y,x) dif = y-x; if nargout > 1 disp('Calculating absolute value') absdif = abs(dif); end end

At the command prompt, call thesubtractfunction with one return value.

diff = subtract(42,13)

diff = 29

Call thesubtractfunction again with two return values.

[dif,absdif] = subtract(2,5)

Calculating absolute value

dif = -3

absdif = 3

Determine how many outputs a function can return.

The functionsubtract在上一步中创建example has two outputs in its declaration statement (difandabsdif).

有趣的=@subtract; nargout(fun)

ans = 2

Determine how many outputs a function that usesvarargoutcan return.

In a file namedmySize.m, create a function that returns a vector of dimensions from thesizefunction and the individual dimensions usingvarargout.

typemySize.m

function [sizeVector,varargout] = mySize(x) sizeVector = size(x); varargout = cell(1,nargout-1); for k = 1:length(varargout) varargout{k} = sizeVector(k); end end

Query how many outputsmySizecan return.

有趣的='mySize'; nargout(fun)

ans = -2

The minus sign indicates that the second output isvarargout. ThemySizefunction can return an indeterminate number of additional outputs.