Graph two curves together (datetime format and double format)

Hi, thank you so much for reading me, i am using matlab 2019a, and i have this problem, i want to graph a function of curvefitting with my original curve, but i can't for this error that appears (attach photo) , i want the two graphs together .......

thank you so much for your valious time

tEnersol=readtable('solar.xlsx','sheet','EneDics');    % read into a table object
tEnersol.Properties.VariableNames={'Rad','Dia'};       % assign variable names
% yr=2014;                                             % need the proper year 
tEnersol.Date=datetime(yr,1,tEnersol.Dia);             % and create a date column
hB=plot(tEnersol.Date,tEnersol.Rad, '.r'); hold on     % bar plot against actual date
hAx=gca;                                               % get axes handle...
xlim([datetime(2014,1,1) datetime(2014,12,12)])        % set limit to cover the full year
hAx.XAxis.TickLabelFormat='MM';                        % show day of MONTH
% xticklabels(cellstr(tEnersol.Date(xticks)))          % use the date string as tick labels
hAx.XTickLabelRotation=45;                             % rotate so can have chance to read...
xlabel('Mes del año, TMYE'), ylabel('Irradiancia solar máxima [KWh/m^2]');
a1= 2329 
b1= 0.6522  
c1= 0.95
a2= 1519  
b2= 0.7781 
c2= -2.545  
d = (1:1:365); 
w = a1.*sin(b1.*d+c1) + a2.*sin(b2.*d+c2)
plot(d,w,'.-b'); hold off 

Answer 1

[Walter Roberson]

hB=plot(tEnersol.Date,tEnersol.Rad, '.r'); hold on     % bar plot against actual date

That is the first plot in the axes, and it establishes that the x axes is to be based upon datetime values.

plot(d,w,'.-b'); hold off 

Your d is not datetime values, just pure numbers. You cannot plot a pure number variable in an axes that is already a datetime axes. So...

D = datetime(yr, 1, d);
plot(D, w, '.-b')

[Ana Soph]

i obtain this (final photo) but i want something like the first photo) and thank you for your explanation

[Ana Soph]

i obtain this with that code:

[Walter Roberson]

If you want something like the first photo, the one that results from the curvefit toolbox, then

hB = plot(tEnersol.Dia, tEnersol.Rad, '.r'); hold on     % bar plot against day of year
xtick(0:50:350);

[Ana Soph]

i tried it but this happens.

[Ana Soph]

or this .. .

[Walter Roberson]

xticks(0:50:350)

[Walter Roberson]

Why are you using d = 1:50:365 ? That is going to give you a very rough w line. Why are you not using d=1:365 ?

[Ana Soph]

thank you , i finally use this code:

tEnersol=readtable('solar.xlsx','sheet','EneDics');    % read into a table object
tEnersol.Properties.VariableNames={'Rad','Dia'};       % assign variable names
yr=2014;                                               % need the proper year 
tEnersol.Date=datetime(yr,1,tEnersol.Dia);             % and create a date column
hB=plot(tEnersol.Date,tEnersol.Rad, '.r'); hold on     % plot against actual date
% xticks(0:50:365);
hAx=gca;                                               % get axes handle...
xlim([datetime(2014,1,1) datetime(2014,12,12)])        % set limit to cover the full year
hAx.XAxis.TickLabelFormat='MM';                        % show day of MONTH
% xticklabels(cellstr(tEnersol.Date(xticks)))          % use the date string as tick labels
hAx.XTickLabelRotation=45;                             % rotate so can have chance to read...
xlabel('Mes del año, TMYE'), ylabel('Irradiancia solar máxima [KWh/m^2]');
% z = fminsearch(@ds,[1339 .05 .12 492.1 .01 1.96])
% fplot(a1.*sin(b1.*d+c1) + a2.*sin(b2.*d+c2), [0,365]) hold off
a1= 1339
b1= 0.00571  
c1= 0.1232
a2= 492.1  
b2= 0.0086
c2= 1.966  
d =(1:365); 
w = a1.*sin(b1.*d+c1) + a2.*sin(b2.*d+c2)
D = datetime(yr, 1, d);
plot(D, w, '.-b')

and obtain this (attach photo) i can put the equation in the figure ?

thank you so much

[Walter Roberson]

text() or legend() to put the equation in. You will probably want to use 'Interpreter', 'latex'

[Ana Soph]

ok, thank you so much !