Convert a string to a real or complex number.
The string must be in one of the following formats where a and b are real
numbers and the complex unit is
If present, a and/or b are of the form [+-]d[,.]d[[eE][+-]d] where
the brackets indicate optional arguments and
'd' indicates zero or
more digits. The special input values
are also accepted.
s may be a character string, character matrix, or cell array. For character arrays the conversion is repeated for every row, and a double or complex array is returned. Empty rows in s are deleted and not returned in the numeric array. For cell arrays each character string element is processed and a double or complex array of the same dimensions as s is returned.
For unconvertible scalar or character string input
a NaN. Similarly, for character array input
str2double returns a
NaN for any row of s that could not be converted. For a cell array,
str2double returns a NaN for any element of s for which
conversion fails. Note that numeric elements in a mixed string/numeric
cell array are not strings and the conversion will fail for these elements
and return NaN.
str2double can replace
str2num, and it avoids the security
risk of using
eval on unknown data.
See also: str2num.