NaN from str2double('1 2 3') on Matlab 2020a

Hi

str2double('1 2 3') returns NaN on Matlab 2020a but works fine on Matlab 2018b & Matlab 2016b (returns: 1 2 3).

How to convert a string of numbers to numbers in the newest Matlab version?

Best,

Dawid

[Stephen23]

For all MATLAB versions the most efficient soluton is:

str = '1 2 3';
vec = sscanf(str,'%f')

Avoid str2num, it contains a hidden eval call...

Answer 1

[Bruno Luong]

"works fine on Matlab 2018b"

Are you sure?

>> version

ans =

    '9.5.0.1298439 (R2018b) Update 7'

>> str2double('1 2 3')

ans =

   NaN

>> str2num('1 2 3')

ans =

     1     2     3

>> 

[Dawid Strzelczyk]

pretty sure:

>> version

ans =

'9.5.0.1033004 (R2018b) Update 2'

>> str2double('1 2 3')

ans =

1 2 3

>> str2num('1 2 3')

ans =

1 2 3

str2num solves the problem, thanks!

[Steven Lord]

That is not the behavior I see.

>> version
ans =
    '9.5.0.1033004 (R2018b) Update 2'

>> str2double('1 2 3')
ans =
   NaN

Are you certain you're using the str2double function included with MATLAB? Alternately it uses sscanf extensively; are you using the version of that function included with MATLAB?

which -all str2double

which -all sscanf

[Bruno Luong]

AFAIK str2double never works on string with multiple numbers.

[James Tursa]

One more data point, PCWIN:

>> version
ans =
    '9.5.0.944444 (R2018b)'
>> str2double('1 2 3')
ans =
   NaN
>> str2num('1 2 3')
ans =
     1     2     3