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Topic: ploting in db
Replies: 5   Last Post: Mar 19, 2013 6:49 PM

 Messages: [ Previous | Next ]
 dpb Posts: 9,850 Registered: 6/7/07
Re: ploting in db
Posted: Mar 19, 2013 6:49 PM

On 3/19/2013 4:25 PM, Steven_Lord wrote:
>
>
> "dpb" <none@non.net> wrote in message
> news:kiaaa6\$s4e\$1@speranza.aioe.org...

>> On 3/19/2013 12:05 PM, Steven_Lord wrote:
>>>
>>>
>>> "Yousef " <yayatoure@hotmail.com> wrote in message
>>> news:kia1ui\$9hl\$1@newscl01ah.mathworks.com...

>>>> Hi Guys,
>>>>
>>>> Can anybody help me to change my y-axis to (db) logarithmic scale..
>>>> part of my code looks like:
>>>>
>>>>
>>>> c=sqrt(abs(data(:,2)).^2 + abs(data(:,3)).^2);

>> ...
>>
>> Steven answered the axis question,

>
> Yes, I did focus on that piece and didn't look at the code.
>

>> I'll simply note that the above can be written more succinctly as
>>
>> c=abs(complex(data(:,2),data(:,3)));
>>
>> The abs() in your expression are purely superfluous since squaring a
>> value makes it positive.

>
> Even more succinctly, you can probably just replace this with a call to
> HYPOT.
>
> http://www.mathworks.com/help/matlab/ref/hypot.html

If have recent-enough version, yes...

>> help hypot

>>

I've not yet learned all the new functions and generally don't use the
gratis new release owing to it overwhelming my old machine, unfortunately...

--

Date Subject Author
3/19/13 Steven Lord
3/19/13 dpb
3/19/13 Steven Lord
3/19/13 dpb
3/19/13 Derek Goring