How to fix "unrecognized table variable name" error?

I have the following code for App Designer which it does exactly what I want.

The code upload a file and then the user has to select the starting date to plot the data on Axes but also the user has to select the ending date. This is done by using "date picker" See the image for the result.

When ever the user change the date of the Start or Ending then the timestamp change on the Axes.

To do that I have to write my code under functions of 'date picker start' and 'date picker ending'. Again the code is working fine but I think I am overwriting it in two different locations.

I want to minimize my code as much as possible because I am just trying to see how it works here. And then I have a different GUI that has many Axes and files to upload.

Here is the main code : And I also uploaded the files that I am working with.

classdef Gui_app < matlab.apps.AppBase

% Properties that correspond to app components

properties (Access = public)

UIFigure matlab.ui.Figure

UIAxes matlab.ui.control.UIAxes

UPLOADButton matlab.ui.control.Button

StartDatePickerLabel matlab.ui.control.Label

StartDatePicker matlab.ui.control.DatePicker

EndingDatePickerLabel matlab.ui.control.Label

EndingDatePicker matlab.ui.control.DatePicker

end

properties (Access = private)

IN1, IN2, tr, tt, value1, value2, data; % Description

end

% Callbacks that handle component events

methods (Access = private)

% Button pushed function: UPLOADButton

function UPLOADButtonPushed(app, event)

app.data=readtable('EKW.csv','ReadVariableNames', true);

end

% Value changed function: StartDatePicker

function StartDatePickerValueChanged(app, event)

app.value1 = app.EndingDatePicker.Value;

app.IN1=datestr(app.value1);

app.value2 = app.StartDatePicker.Value;

app.IN2=datestr(app.value2);

Time_Stamp=datetime(app.data.Timestamp,'InputFormat','yyyy-MM-dd''T''HH');

app.tt = timetable(Time_Stamp,app.data.YYY);

app.tr = timerange(app.IN2,app.IN1);

daterange = app.tt(app.tr,:);

plot(app.UIAxes,daterange.Time_Stamp,daterange.Var1)

end

% Value changed function: EndingDatePicker

function EndingDatePickerValueChanged(app, event) % I was trying to write everything under this function but then the ....

% graph will not continously once the user change the date of StartDatePicker

app.value1 = app.StartDatePicker.Value;

app.IN1=datestr(app.value1);

app.value2 = app.EndingDatePicker.Value;

app.IN2=datestr(app.value2);

Time_Stamp=datetime(app.data.Timestamp,'InputFormat','yyyy-MM-dd''T''HH'); % Also, I want to write this only on one location ..

% so I do not have to read the file everytime that I want to use Time_Stamp

% I tried to make 'Time_Stamp' as a properties but it give me the following error on 'Plot function'

app.tt = timetable(Time_Stamp,app.data.YYY);

app.tr = timerange(app.IN1,app.IN2);

daterange = app.tt(app.tr,:);

plot(app.UIAxes,daterange.Time_Stamp,daterange.Var1) % unrecognized table variable name Time_Stamp

% I did use app.Time_Stamp but still not working

end

end

Answer 1

[Srijith Kasaragod]

Hi @Steven Shaaya,

You can assign a single 'ValueChangedFcn' callback for both the date pickers to remove redundant code from your app. Refer the attached app to see how this can be achieved.

Regards,

Srijith.