matrix with logicals and doubles

is it possible to create a matrix where part of it is defined as doubles and others as logicals?

Answer 1

[Matt Fig]

No. Matrices cannot have mixed types. You could use a cell array, like:

A = {true, 4;false, 5;true 9}

or have a matrix which holds both values to be used when needed.

A = [0 1 2 0;3 0 5 6;1 1 1 0]

% When a logical is needed:
LA = logical(A)

[Walter Roberson]

Note also that for the purposes of any logical test, values which are 0 (in any numeric data type) are considered false, and non-zero non-nan values are considered to be true. Thus, in many cases there is no need to explicitly use logical values at all.

logical vs double does make a difference for indexing. Also there are a number of routines that consider logical to signal black and white but consider double to signal relative intensities. The two are not completely interchangeable, but they often are.