       Re: Plot with x value in Log

• To: mathgroup at smc.vnet.net
• Subject: [mg101204] Re: Plot with x value in Log
• From: Bill Rowe <readnews at sbcglobal.net>
• Date: Fri, 26 Jun 2009 06:54:04 -0400 (EDT)

```On 6/25/09 at 7:13 AM, breno.minzon at gmail.com (Breno Tresoldi Minzon)
wrote:

>I need to plot an Integral, that i need to solve numerically. I need
>to plot 10Log10[x] versus result of integral. If i plot

>Plot[nIntegrate[<my func here, in x>],{x,100,1,-1}]

>is easy, but the plot is wrong. i need to do 10Log10 of x, not only
>x. But if i plot

>LogLinearPlot[nIntegrate[<my func here, in x>],{x,100,1,-1}] the
>plot is a Log in x, but the values that appear isn't in
>log...How can i do this? i search alot in google, in
>help, in anywhere...What i'm doing wrong?

You simply aren't using the best built-in function for the task
at hand. Use ParametricPlot.

The syntax would be:

ParametricPlot[{10 Log[10,x],f[x]},{x,xmin,xmax}]

Note, unlike most plot functions the default aspect ratio for
ParametericPlot is 1. If the range for f[x] is significantly
different than the range for 10 Log[10, xmin] to 10 Log[10,
xmax] your plot likely not be what you want. To get the more
typical aspect ratio you will need to override the default by
specifying ApectRatio->1/GoldenRatio

```

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