Difficulties having log and linear y axes on same figure

I am trying to plot a graph that has: left y axis in a logarithmic scale and a right y axis in a linear scale...for some reason I am not able to do it. (The x axis is always logarithmic in this case).

Any help is appreciated, as I can't seem to get my head around what is wrong:

figure(1)

FontSizeCaption = 18;
FontSizeLabel = 16;
LineWidth= 1.5;

loglog(CSS_NF_1,EM_NF_1,'-rsq','LineWidth',LineWidth)
hold on
loglog(CSS_NF_1,VM_NF_1,'-bo','LineWidth',LineWidth)

caption = sprintf('Linear Viscoelastic Region Analysis \n (KHAp)');
title(caption, 'FontSize', FontSizeCaption,'FontName','CMU Sans Serif');

xlbl_N=xlabel('Complex Shear Strain (%)');
set(xlbl_N,'FontSize',FontSizeLabel,'FontName','CMU Sans Serif');

yyaxis left

ylbll_N=ylabel('Elastic Modulus, Viscous Modulus(Pa)');
set(ylbll_N,'FontSize',16,'FontName','CMU Sans Serif');

yyaxis right
semilogx(CSS_NF_1,PA_NF_1,'-^','LineWidth',LineWidth,'Color','#377E22')

ylblr_N=ylabel('Phase Angle (^{\circ})')
ylim([0 90])
set(ylblr_N,'FontSize',FontSizeLabel,'FontName','CMU Sans Serif','Color','#377E22');

ax = gca;
ax.YAxis(1).Color = 'k';
ax.YAxis(2).Color = '#377E22';

Side point: I also can't seem to separate my y labels in lines by using {\n}

Answer 1

[Star Strider]

The data are missing so I can’t run the posted code.

Try something like this —

x = linspace(0,100);
y1 = 5.1+5*sin(2*pi*x*3);
y2 = 2.1+2*cos(2*pi*x*3);

figure
yyaxis left
plot(x, y1)
ylabel('Log Scale')
yyaxis right
plot(x, y2)
ylabel('Linear Scale')
Ax = gca;
% Ax.YAxis(1)
% Ax.YAxis(2)
Ax.YAxis(1).Scale = 'log';
Ax.YAxis(2).Scale = 'linear';

Setting the axis properties after the plots are created is straightforward. See Modify Properties of Charts with Two y-Axes.

.

[Herbert Middleton]

Figured out that the problem was my data set (not large enough)...so I defined the ylim to allow for a log scale. Thanks!

[Star Strider]

As always, my pleasure!

Answer 2

[Voss]

This is your code, with some random data. It seems to do the right thing, as far as the axes scales (linear/log) being correct.

To get the ylabel on multiple lines, use sprintf with \n (like you are already doing with the title).

CSS_NF_1 = logspace(-1,2,25);
EM_NF_1 = rand(size(CSS_NF_1));
VM_NF_1 = rand(size(CSS_NF_1));
PA_NF_1 = 90*rand(size(CSS_NF_1));

figure(1)
 
FontSizeCaption = 18;
FontSizeLabel = 16;
LineWidth= 1.5;
 
loglog(CSS_NF_1,EM_NF_1,'-rsq','LineWidth',LineWidth)
hold on
loglog(CSS_NF_1,VM_NF_1,'-bo','LineWidth',LineWidth)
 
caption = sprintf('Linear Viscoelastic Region Analysis \n (KHAp)');
title(caption, 'FontSize', FontSizeCaption,'FontName','CMU Sans Serif');
 
xlbl_N=xlabel('Complex Shear Strain (%)');
set(xlbl_N,'FontSize',FontSizeLabel,'FontName','CMU Sans Serif');
 
yyaxis left
 
ylbll_N=ylabel(sprintf('Elastic Modulus\nViscous Modulus\n(Pa)'));
set(ylbll_N,'FontSize',16,'FontName','CMU Sans Serif');
 
yyaxis right
semilogx(CSS_NF_1,PA_NF_1,'-^','LineWidth',LineWidth,'Color','#377E22')
 
ylblr_N=ylabel('Phase Angle (\circ)');
ylim([0 90])
set(ylblr_N,'FontSize',FontSizeLabel,'FontName','CMU Sans Serif','Color','#377E22');
 
ax = gca;
ax.YAxis(1).Color = 'k';
ax.YAxis(2).Color = '#377E22';

[Herbert Middleton]

Thank-you so much!! Is there a way I can make the x-axis title have 2 different colours as well? Red and blue for example

[Voss]

% use '{\color{<color>}<text_string>}'
xlbl_N = xlabel('{\color{blue}Complex Shear }{\color{red}Strain (%)}');
set(xlbl_N,'FontSize',16,'FontName','CMU Sans Serif');

% inside sprintf, use \\ instead of \
caption = sprintf('{\\color{green}Linear Viscoelastic Region Analysis}\n{\\color{orange}(KHAp)}');
title(caption,'FontSize',18,'FontName','CMU Sans Serif');

[Herbert Middleton]

Amazing, thanks!

[Voss]

You're welcome!