How can I replace eval and rewrite the below line?

 Hi..How can I replace eval..when I tried this way

   Speed =Data.(cycle_name(1:end-4)).Data;
   Time=Time.(cycle_name(1:end-4)).Time;

it is giving me some error saying Undefined variable "Data" or class "Data.FTP.Data".

        eval(['Speed = ' cycle_name(1:end-4) '.Data;']);
          eval(['Time = ' cycle_name(1:end-4) '.Time;']);

[Stephen23]

The solution will be to load your data properly, into an output variable (which happens to be a structure). If you want help with this then please edit your question and upload a sample .mat file so that we can check our code on your data.

[Harini pushparaj]

Hi ..I am attaching both FTP file and the code

Answer 1

[OCDER]

NEW ANSWER:

Inside the FTP.mat is a variable called ts storing the timeseries object. To access the contents inside ts, do this:

Z = load(fullfile('..\cycledata',cycle_name))  % Z is a temporary variable

Speed = Z.ts.Data;
Time  = Z.ts.Time;

OLD ANSWER:

Assuming you have a non-scalar structure called cycle_name that has at least 5 elements, this should work:

Speed = cycle_name(1:end-4).Data;
Time  = cycle_name(1:end-4).Time;

[Harini pushparaj]

Struct contents reference from a non-struct array object.

Error in Vehicle_Model_init (line 41) Speed = cycle_name(1:end-4).Data;..it's not working

[Harini pushparaj]

load(fullfile('..\cycledata',cycle_name)) eval(['Speed = ' cycle_name(1:end-4) '.Data;']); eval(['Time = ' cycle_name(1:end-4) '.Time;']); Time_interp = (Time(1):Ts:Time(end))' Speed_interp = (interp1(Time,Speed,Time_interp)); This way it works...but i want to replace eval...

[OCDER]

Oh, I see - cycle_name is some sort of string/char. What is stored inside this file being loaded? Using load without an output makes it hard to debug, as you're "poofing" variables out of no where into your workspace. Try this:

Z = load(fullfile('..\cycledata',cycle_name))  

Speed = Z.(Z.cycle_name(1:end-4)).Data;
Time  = Z.(Z.cycle_name(1:end-4)).Time;

[Harini pushparaj]

Cycle_name='FTP.mat' inside FTP.mat I have Data and Time

                 Data: [86400×1 double]
            DataInfo: [1×1 tsdata.datametadata]
                Time: [86400×1 double]
               TimeInfo: [1×1 tsdata.timemetadata]

[OCDER]

Z = load(fullfile('..\cycledata',cycle_name))  
Speed = Z.Data;
Time  = Z.Time;

[Harini pushparaj]

Reference to non-existent field 'Data'.

Error in Vehicle_Model_init (line 41) Speed =Z.Data;

[OCDER]

Odd... Try this for debugging purposes on the matlab command window. What are the outputs?

>> load(fullfile('..\cycledata',cycle_name))  
>> disp(fullfile('..\cycledata',cycle_name))  %show file name
>> whos  %show variables that are loaded

[Harini pushparaj]

disp(fullfile('..\cycledata',cycle_name)) ..\cycledata\FTP.mat

Name Size Bytes Class Attributes

Ah_zero               1x1                 8  double                  
CurrentFolder         1x55              110  char                    
FTP                   1x1             30362  timeseries              
Km_end                1x1                 8  double                  
Q_zero                1x1                 8  double                  
SOC_zero              1x1                 8  double                  
Ts                    1x1                 8  double                  
Z                     1x1             30538  struct                  
alpha_J_charge        1x1                 8  double                  
alpha_J_life          1x1                 8  double                  
alpha_J_range         1x1                 8  double                  
alpha_J_speed         1x1                 8  double                  
cycle_name            1x7                14  char                    
km_percorsi_zero      1x1                 8  double

[OCDER]

I don't see "Data" or "Time" in this FTP.mat. But you did say FTP.mat has them, right? Where does this come from:

                 Data: [86400×1 double]
            DataInfo: [1×1 tsdata.datametadata]
                Time: [86400×1 double]
               TimeInfo: [1×1 tsdata.timemetadata]

I think there's some missing info. In the original question, EDIT it to attach the full code (the one you're trying to replace eval with) and FTP.mat file.

[Harini pushparaj]

Please see the pic..attached one with red circles

[Stephen23]

@Harini pushparaj: You have been asked twice to upload your .mat file. I will ask a third time: please edit your question and upload a sample .mat file.

[OCDER]

Oh.... FTP.mat stores the time series data, ts...

Z = load(fullfile('..\cycledata',cycle_name))
Speed = Z.ts.Data;
Time  = Z.ts.Time;

[Harini pushparaj]

OLD ANS:When i used this Speed = cycle_name(1:end-4).Data; Time = cycle_name(1:end-4).Time; error saying Struct contents reference from a non-struct array object.

Error in Vehicle_Model_init (line 30) Speed = cycle_name(1:end-4).Data; NEW ANS: error saying : Reference to non-existent field 'ts'.

Error in Vehicle_Model_init (line 31) Speed = Z.ts.Data;

[OCDER]

Is this the same FTP.mat file, or is there another FTP.mat file? The one you uploaded has a ts timeseries variable.

[Harini pushparaj]

I have only one FTP file..its the same ...

[OCDER]

Starting from the beginning... Set your working directory to the folder storing FTP.mat. Then do this:

clear
load('FTP.mat')

Do you atleast get ts variable show up in your workspace?

Note that "..\cycledata\FTP.mat" means go to the folder above the current directory, then to cycledata folder, then the FTP.mat file inside there. My hunch is, there is another FTP.mat file, just not in your current directory that you want.

The FTP.mat file you showed in the screenshot picture DOES show the ts variable.

HOWEVER, the result from whos command does not show the ts variable, and instead show a variable called FTP that is the timeseries. Hence, it seems you are not loading the correct .mat file.