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## Re: Exponential notation in tick labels?

 From: Matthias Brennwald Subject: Re: Exponential notation in tick labels? Date: Wed, 9 Sep 2009 16:07:00 +0200

```
On Sep 9, 2009, at 3:38 PM, Carlo de Falco wrote:

```
```2009/9/9 Carlo de Falco <address@hidden>:
```
```2009/9/9 Matthias Brennwald <address@hidden>:
```
Thanks, this does the trick! Now I could even try to adapt this to the
```"10^n" notation... I don't know a direct way to use sprintf(...) to
print numbers in  the 10^n format, but I guess it is feasible by
manipulating the ticklabels using string functions somehow.
```
```

octave-3.2.2:76> x= [1e5:1e5:1e6];
octave-3.2.2:77> plot(x,x);
octave-3.2.2:78> axis tight
octave-3.2.2:79> xt = get(gca, 'xtick');
octave-3.2.2:80> x_ex = floor(log10(xt));
octave-3.2.2:81> x_mant = xt./10.^x_ex;
octave-3.2.2:82> set(gca, 'xticklabel', sprintf('%1.1fx10^{%d}|',
x_mant, x_ex));

Note that if one of the ticks were labeled "0" it would need to be
handled separately
(that's the reason for "axis tight")
```
```
sorry, I made  mistake in the call to sprintf above..
the approach below should work correctly and also andle the
zeros automatically...

function [ex, mant] = exp_notation (x)
nz = find(x);
ex(nz) = floor(log10(abs(x(nz))));
mant(nz) = x(nz)./10.^ex(nz);
endfunction

octave-3.2.2:108> x= [-1e6:1e5:1e6];
octave-3.2.2:109> plot(x,x);
```
octave-3.2.2:110> xt = get(gca, 'xtick');[xex,xmant] = exp_notation (xt); octave-3.2.2:111> yt = get(gca, 'ytick');[yex,ymant] = exp_notation (yt);
```octave-3.2.2:112> set(gca, 'xticklabel', sprintf('%3.3gx10^{%d}|',
[xmant; xex](:)));
octave-3.2.2:113> set(gca, 'yticklabel', sprintf('%3.3gx10^{%d}|',
[ymant; yex](:)));
```
```
Even better, thanks a bunch!

Matthias

```