From char to number

S = '"10:58",297.98,0.25,0.15,66.5,1.194,-0.31,-0.27,71.1,0.966,""';
C = textscan(S, '"%[^"]",%f,%f,%f,%f,%f,%f,%f,%f,%f,%*s', 'CollectOutput', 1);
thetimestr = C{1}{1};
thenums = C{2};

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paul kaam 2015-5-12

i do not understand what u mean with that? rt?

paul kaam 2015-5-12

在 MATLAB Online 中打开

Now it is between '' with cellstr:

>> S

S =

"12:15",333.98,0.06,0.06,65.3,0.975,0.02,0.10,72.2,1.002,""

>> cellstr(S)

ans =

'"12:15",333.98,0.06,0.06,65.3,0.975,0.02,0.10,72.2,1.002,""'

>> C = textscan(ans, '"%[^"]",%f,%f,%f,%f,%f,%f,%f,%f,%f,%*s', 'CollectOutput', 1); Error using textscan First input must be of type double or string.

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Answer 3

omax ali 2020-11-5

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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/216355-from-char-to-number#answer_535170

i just write this for new ones who searching:

to change some value like a=["1","2.2","3",......] to number format we can do as:

b=char(a);

c=str2num(b);

c gives you the numbers.

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Walter Roberson 2020-11-6

编辑：Walter Roberson 2020-11-6

在 MATLAB Online 中打开

a=["1","2.2","3"]
a = 1×3 string array
    "1"    "2.2"    "3"
double(a)
ans = 1×3
    1.0000    2.2000    3.0000

This relies upon a being datatype string and not cell array of character vector:

a = {'1', '2.2', '3'}
a = 1x3 cell array
    {'1'}    {'2.2'}    {'3'}
str2double(a)
ans = 1×3
    1.0000    2.2000    3.0000
●

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Answer 4

Philipp Prestel 2023-6-24

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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/216355-from-char-to-number#answer_1261893

编辑：Philipp Prestel 2023-6-24

在 MATLAB Online 中打开

Again for someone stumbling over this:

if this is your char array: ' "10:58 ", 297.98, 0.25, 0.15, 66.5, 1.194, -0.31, -0.27, 71.1, 0.966,"" '

and these are your values:

val1 (1,1) datetime = 10:58

val2 (1,1) double = 297.98

...

val10 (1,1) double = 0.966

First of all, i want to say something about the array itself; you don't need any qotation marks around the time, it's arbitrary since you already have a char array. Next is the "" at the end, if it is supposed to be a empty string it's fine, otherwise remove it.

This applies if you're indexing stays the same for other arrays you may want to decode, if the indexing varries for some reasons there are better ways of doing dynamic identification.

Generally, I would advise against using char arrays to pass around data. If you have to do it or read from a text file make sure what you save is compatible with sscanf, fscanf, readtable or anything using Matlabs format spec. Json works as well with jsonencode and jsondecode.

if you can't get around it, I found the following to work:

value_char = '"10:58",297.98,0.25,0.15,66.5,1.194,-0.31,-0.27,71.1,0.966,""';
value_char = erase(value_char,'"');
value_cellstr = split(value_char,',');
time_str = string(value_cellstr{1});
value_time = datetime(time_str,InputFormat='HH:mm')
value_time = datetime
   24-Jun-2023 10:58:00
num_cellstr = value_cellstr(2:end-1);
nums = cellfun(@str2num,num_cellstr)
nums = 9×1
  297.9800
    0.2500
    0.1500
   66.5000
    1.1940
   -0.3100
   -0.2700
   71.1000
    0.9660
last_str = erase(value_cellstr{end},'"');
last_str = string(last_str)
last_str = ""

This isn't the best implementation but it shows what you can do. Split the array into cell string using ',' as a delimiter then convert the individual cellstirngs to the format you want.

If you want it more adaptive you can also write a small function to use for cellfun, which identifies what type you want a value in and then does the conversion. Which might look something like this:

value_char = '"10:58",297.98,0.25,0.15,66.5,1.194,-0.31,-0.27,71.1,0.966,""';
value_cellstr = split(value_char,',');
nums = cellfun(@convert2type,value_cellstr,UniformOutput=false)
nums = 11×1 cell array
    {["10:58" ]}
    {[297.9800]}
    {[  0.2500]}
    {[  0.1500]}
    {[ 66.5000]}
    {[  1.1940]}
    {[ -0.3100]}
    {[ -0.2700]}
    {[ 71.1000]}
    {[  0.9660]}
    {[""      ]}
function A_convert =  convert2type(A)
    arguments 
        A char {mustBeTextScalar} 
    end
    if contains(A,'"')
        A_convert = erase(A,'"');
        A_convert = string(A_convert);
    else
        A_convert = str2num(A);
    end
end 