How to set YTickLabel in double y-axis plot?

The simplified code is as following:

 x=[2,3,4,5,6,7];
 y1=[ 1,    1,  1.2,  1.2,   1,    1];
 y2=[ 0, 0.01, 0.02, 0.02,   0, 0.01];
 fig1 = figure;
 [ax,h1,h2] = plotyy(x,y1, x,y2, 'plot');
 set(get(ax(1),'YLabel'),'String','y1','fontsize',14)
 set(get(ax(2),'YLabel'),'String','y2','fontsize',14)
 legend('y1','y2');
 xlabel('x')
 ylim(ax(1), [0.7, 1.3])
 ylim(ax(2), [0, 0.03])
 print(fig1, '-dpng', 'test1')

The figure plot is like

I wanted to set the digits of YTick, so I tried something like

 set(get(ax(1),'YTick'), [1.00, 1.05, 1.10, 1.15, 1.20]);
 set(get(ax(1),'YTickLabel'), [1.00, 1.05, 1.10, 1.15, 1.20]);

or

 set(get(ax(1),'YTick'), {'1.00', '1.05', '1.10', '1.15', '1.20']);
 set(get(ax(1),'YTickLabel'), {'1.00', '1.05', '1.10', '1.15', '1.20']);

or

 set(get(ax(1),'YTick'), str2mat('1.00', '1.05', '1.10', '1.15', '1.20']);
 set(get(ax(1),'YTickLabel'), str2mat('1.00', '1.05', '1.10', '1.15', '1.20']);

All went wrong.

So my question is, how to set the digits of y axis label?

And why the left YTick is from 1.0 to 1.2 but leaves all other ticks?

And more generally, how to handle this `gca` properties?

Answer 1

[dpb]

Isn't it annoying that plot isn't intelligent-enough to use a consistent numeric format for tick labels??? I've complained about this for almost 30 years now... :(

Anyway, it's relatively easy to fix...

Long-winded way; easier to see what did...

yt=get(hAx(1),'ytick');  % retrieve the tick marks from desired axes
set(hAx(1),'yticklabel',num2str(yt.','%.2f'))  % set with a desired format same values

You can, of course, dispense with the temporary -- easiest to write w/o getting fouled up with parentheses nesting if start from inside out...

set(hAx(1),'yticklabel',num2str(get(hAx(1),'ytick').','%.2f'))

NB: the transpose; it's important as the tick values are returned as a row vector and num2str needs a column vector or the values will all be returned as a single long string, not an array of strings.

[Albert Bing]

Thank you very much for your answer. (I hate that stupid format too!)

It's just that I'm sorry but I don't know this part

 num2str(yt.'),'%.2f')

Why is there a dot . after yt , and a single quotation mark ' followed by a right parenthesis ) ?

If those deleted, say

 num2str(yt,'%.2f')

then every ticklabel becomes the same, 1.001.051.101.151.20.

[dpb]

>> help transpose
.' Transpose.
  X.' is the non-conjugate transpose.

I commented specifically on the need and what happens without it...

[Albert Bing]

Ah, transpose, thank you!

So that better be

 num2str(yt.', '%.2f')

Answer 2

[Mike Garrity]

Or in R2016a:

ax(1).YAxis.TickLabelFormat = '%.2f';