Re: st: number of dates in x axis

[Maria Ana Vitorino <vitorino@wharton.upenn.edu>]

Thanks Nick.
I tried running your example but I got the error message "invalid  
label specifier, :  15341 15400 15461 ..."
Any suggestions?
Thanks!
Ana

On May 24, 2011, at 4:20 AM, Nick Cox wrote:

> There is relevant material at
>
> Stata 7: How can I get "nice" date labels on a graph?
>
> http://www.stata.com/support/faqs/graphics/nicedate.html
>
> StataCorp have added this annotation:
>
> "Note: This FAQ is relevant for users of releases prior to Stata 8.
> For Stata 8 see update from 12 September 2003."
>
> In fact the techniques there do remain useful for some problems.
>
> Here's an example with different data. Here I decide that I want
> labels every 2 months from 1 January 2002 to 1 January 2003. I loop
> over the dates and put them in a bag, namely a local macro.
>
> sysuse xtline1
> xtset person day
>
> forval i = 1(2)11 {
> 	local thisdate = mdy(`i', 1, 2002)
> 	local mydates `mydates' `thisdate'
> }
>
> local thisdate = mdy(1,1,2003)
> local mydates `mydates' `thisdate'
>
> xtline calories, overlay xlabel(`mydates', format(%d_m_Y) ang(v))
>
> See also
>
> SJ-7-4  gr0030  . Stata tip 55: Better axis labeling for time points/ 
> intervals
>        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   
> N. J. Cox
>        Q4/07   SJ 7(4):590--592                                 (no  
> commands)
>        tip on labeling graphs for time points and time intervals
>
>
> On Tue, May 24, 2011 at 4:45 AM, Maria Ana Vitorino
> <vitorino@wharton.upenn.edu> wrote:
>
> > I have the following data:
> >
> >
> >    +------------------------+
> >    | Person   Weight      Date    |
> >    |------------------------|
> >  1. |  Name1       50      17988  |
> >  2. |  Name1       55      18110  |
> >  3. |  Name1       50      18141  |
> >  4. |  Name1       45      18171  |
> >  5. |    ...        .      . |
> >    |------------------------|
> >  6. |  Name2       85      18110 |
> >  7. |  Name2       88      18171 |
> >  8. |  Name3       68      17988 |
> >  9. |    ...        .                       . |
> > 10. |     ..        .      .                 |
> >    |------------------------|
> > 11. |  NameN        .               . |
> >    +------------------------+
> >
> > The labels for the date variables are the months' names (plus year)  
> > (e.g.
> > "jan2006", "feb2007", etc)
> >
> > If I do something like:
> >
> > xtline Weight , overlay  i(Person) t(Date) xlab(, valuelabel)
> >
> > The month names show up on the xaxis BUT only every 6 months or so.  
> > How can
> > I control the number of "ticks" (AND month names ) that show up on  
> > the
> > x-axis? (suppose I want a tick every 2 months or even every month)
>
> *
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> *   http://www.stata.com/help.cgi?search
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> *   http://www.ats.ucla.edu/stat/stata/

*
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