Hi Tommaso,
I looked closer at your examples. I agree with you that the first one
transform the following labels:
-80 -60 -40 -20 0 20 40 60 80
into:
80 60 40 20 0 -20 -40 -60 -80
But, seems to me the 2nd example transform:
0 20 40 60 80 100 120 140 160 180
into:
90 70 50 30 10 -170 -150 -130 -110 -90
Which, I guess, is not what you want. I think you did a mistake in your
2nd example.
Cheers, Olivier
On Tue, 9 Mar 2004, Tommaso Chiarusi wrote:
>
> Hello everybody:
>
> OS Linux RH 9
> ROOT 3.10/02 16 December 2003
>
> well, I need to reset the labels onto an histogram.
> It has the x axis which ranges from 0 to +180
> I like it to span from +90 to -90 (yes from positive to negative
> like 90 80 70..10 0 -10 ... -80 -90).
>
> So decided to
> TGaxis method together with a function
>
>
> So I've written the function:
>
> double funz(double *x,double *par)
> {
> double fu=0;
> fu = -x[0];
> return fu;
> }
>
> and in the body of the macro,
>
> TF1 *f = new TF1("f",funz,-90,90,0);
> TGaxis *tga = new TGaxis(0,0,180,0,"f",510);
> tga->Draw();
>
> and it works!
>
> note that the spanning of the new scale is independent from the original
> range.
> -----
> THE QUESTION:
>
> Why the following doesn't give the same result?
>
> I redefine the function,
>
> double funz(double *x,double *par)
> {
> double fu=0;
> if(x[0]<=90) fu = 90 -x[0];
> if(x[0]>90) fu = x[0]-270;
>
> return fu;
> }
>
> and in the body of the macro,
>
> TF1 *f = new TF1("f",funz,0,180,0);
> TGaxis *tga = new TGaxis(0,0,180,0,"f",510);
> tga->Draw();
>
> note the different range for f
>
> Best regards, Tommaso
>
> P.S.
> is this mailing list hard-contamined by spam?
> is it true that it will be removed by the CERN mailing list?
>
>
>
>
--
Org: CERN - European Laboratory for Particle Physics.
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