Matlab Coder error : converting datetime Format error

I have a problem about Matlab Coder... Actually, The code is correctly run in Matlab, but I want to use Matlab coder. Coder makes error, when I want to change datetime Format. For example, variable DateTime is type of datetime, 2017-05-01 00:00, 2017-05-01 00:15, ...... 2017-09-30 23:45 and I want to change it only year and date like, 20170501, 20170501, ...... , 20170930. That's why I make the code in matlab, d1 = datetime(DateTime, 'Format', 'uuuuMMdd');
DateTime = table2array(datatable(1:row/4,1)); % 2017-05-01 00:00, 2017-05-01 00:15, ...... 2017-09-30 23:45 d1 = datetime(DateTime, 'Format', 'uuuuMMdd'); % 20170501, 20170501, ...... , 20170930
In Matlab, it works correctly. But Matlab Coder can't call the function. I want to know how I can solve this problem...TT

 Accepted Answer

Use the dateType argument for the datetime function
d1 = datetime(DateTime, 'dateType', 'yyyymmdd'); % use the dateType argument
instead of
d1 = datetime(DateTime, 'Format', 'uuuuMMdd'); % 20170501, 20170501, ...... , 20170930

4 Comments

TT it doesn't not work in matlab...TT Coder also...TT The error report said that 'Undefinded function or variable 'processedVarArgin'. The first assignment to a local variable determines its class.'
it seems you are converting table data to array. Convert the table data to cell array as shown below and then use the Format argument
DateTime = table2cell(datatable(1:row/4,1))); % convert the table data to cell array
d1 = datetime(DateTime, 'Format', 'yyyyMMdd'); % use the Format argument
Use MM to represent month instead of mm which represents minutes
In the table, there is datetime type. That's why I use table2array... Because value of type 'datetime' in the table, it can't be convertible to 'cell'.
I have a problem only in Matlab Coder... I want to convert from matlab code to c code. Actually my original code has no problem in matlab, but it happens only when I use Matlab Coder codegen...TT Is the correct solution for Matlab Coder?? TT
Ok, for some reason, Matlab coder doesnt support datetime functions
D = datetime({'2017-05-01 00:00', '2017-05-01 00:15'})
D = 1×2 datetime array
01-May-2017 00:00:00 01-May-2017 00:15:00
T = table(D,'VariableNames',{'D'})
T = table
D __________________________________________ 01-May-2017 00:00:00 01-May-2017 00:15:00
DateTime = table2array(T);
d1 = datetime(DateTime, 'Format', 'uuuuMMdd')
d1 = 1×2 datetime array
20170501 20170501

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More Answers (1)

Can you try this once
d1 = datestr(datetime, 'yyyymmdd')
d1 = '20221212'

1 Comment

it still doesn't work... alarm that codegen is not supported datestr method.

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Products

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R2022b

Asked:

on 12 Dec 2022

Edited:

on 14 Dec 2022

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