While using "hold on" to create a graph with multiple graphs together, the logarithmic scale on x axis is not applied.

I want to create a multiple graph using a logarithmic scale on the x-axis, to be able to see the differences between the different values on y-axis. Altough the scale on x-axis is linear and not logarithmic. Is there another way to do what I intend, using a different function?

Thanks in advande,

Here's the code i used:

pi_1=[1 1 0.643 0.472 0.371 0.297]';
pi_08=[1 1 0.632 0.467 0.367 0.295]';
pi_05=[1 1 0.614 0.459 0.362 0.291]';
pi_01=[1 1 0.588 0.448 0.354 0.285]';
s=[3.394 2.400 1.697 1.200 0.849 0.600]';
figure(1)

hold on
cum1=semilogx(s, pi_1); 
cum08=semilogx(s,pi_08); 
cum05=semilogx(s, pi_05);
cum01=semilogx(s, pi_01);

hold off
xlabel('Calibre, mm');
ylabel('Pi');
grid on
title('Cumulante Produto Final')

legend('Pa=1.000','Pa=0.800','Pa=0.500','Pa=0.100');

cum1.LineStyle = '-';
cum1.Color = 'blue';
cum1.Marker = 'o';


cum08.LineStyle = '-';
cum08.Color = 'red';
cum08.Marker = 'o';

cum05.LineStyle = '-';
cum05.Color = 'green';
cum05.Marker = 'o';

cum01.LineStyle = '-';
cum01.Color = 'magenta';
cum01.Marker = 'o';

Answer 1

[Voss]

One way to fix this is to set the 'XScale' of the axes to 'log' explicitly.

pi_1=[1 1 0.643 0.472 0.371 0.297]';
pi_08=[1 1 0.632 0.467 0.367 0.295]';
pi_05=[1 1 0.614 0.459 0.362 0.291]';
pi_01=[1 1 0.588 0.448 0.354 0.285]';
s=[3.394 2.400 1.697 1.200 0.849 0.600]';
figure(1)

set(gca(),'XScale','log') % this can go anywhere from this line down

hold on
cum1=semilogx(s, pi_1); % these can be plot() or semilogx() now
cum08=semilogx(s,pi_08); 
cum05=semilogx(s, pi_05);
cum01=semilogx(s, pi_01);

hold off
xlabel('Calibre, mm');
ylabel('Pi');
grid on
title('Cumulante Produto Final')

legend('Pa=1.000','Pa=0.800','Pa=0.500','Pa=0.100');

cum1.LineStyle = '-';
cum1.Color = 'blue';
cum1.Marker = 'o';


cum08.LineStyle = '-';
cum08.Color = 'red';
cum08.Marker = 'o';

cum05.LineStyle = '-';
cum05.Color = 'green';
cum05.Marker = 'o';

cum01.LineStyle = '-';
cum01.Color = 'magenta';
cum01.Marker = 'o';

[João Sá Pereira]

Tanhk you, it worked perfectly!!

[Voss]

You're welcome!

Answer 2

[Voss]

One way to fix this is to put the hold on afer the first semilogx() call.

pi_1=[1 1 0.643 0.472 0.371 0.297]';
pi_08=[1 1 0.632 0.467 0.367 0.295]';
pi_05=[1 1 0.614 0.459 0.362 0.291]';
pi_01=[1 1 0.588 0.448 0.354 0.285]';
s=[3.394 2.400 1.697 1.200 0.849 0.600]';
figure(1)

cum1=semilogx(s, pi_1); 
hold on
cum08=semilogx(s,pi_08); 
cum05=semilogx(s, pi_05);
cum01=semilogx(s, pi_01);

hold off
xlabel('Calibre, mm');
ylabel('Pi');
grid on
title('Cumulante Produto Final')

legend('Pa=1.000','Pa=0.800','Pa=0.500','Pa=0.100');

cum1.LineStyle = '-';
cum1.Color = 'blue';
cum1.Marker = 'o';


cum08.LineStyle = '-';
cum08.Color = 'red';
cum08.Marker = 'o';

cum05.LineStyle = '-';
cum05.Color = 'green';
cum05.Marker = 'o';

cum01.LineStyle = '-';
cum01.Color = 'magenta';
cum01.Marker = 'o';