How to change lines' color in the plot region with a loop in xtline?

[Ting Liu]

Hi all, I'm using xtline to make a graph of predicted rate of change over time and I have 134 lines (id) altogether, whose color need to be changed into black instead of motley fashion. Since the options have exceeded the assumed upper limit of 70, I can't make that with
"xtline ... if ..., t(time) i(id) overlay plot1(lc(black)) ///
plot2(lc(black)) plot3(lc(black)) plot4(lc(black)) plot5(lc(black)) ///
plot6(lc(black)) plot7(lc(black)) plot8(lc(black)) plot9(lc(black)) ///".

I tried "xtline ... if ..., t(time) i(id) overlay forv i =1/134 {
ploti(lc(black))
} ". However, forv is not allowed as an option for xtline.

So, could you please tell me how to realize it with a loop? Many thanks in advance.

[Maarten Buis]

The easiest way is not to use xtline, but just twoway line with the connect(J) option, something like:

xtset id time
twoway line var time, connect(J)

[Ting Liu]

Thanks, Maarten. But the graph after "twoway line predictedrnfl time if PROG_OD==4 | PROG_OD==5, connect (direct) lc(black)" is like this:
,
which is not what I want.
Can I make it look like:
?
Thanks again.

[Rich Goldstein]

try sorting the data by id and time before you graph it

[Ting Liu]

Yes, I've sorted id and time before that.

[Rachael Wills]

Have you considered modifying a graph scheme to achieve this?

For instance, you could save your own scheme file in your ado folder such as 'myscheme.scheme' and then call this option when you produce your graph.

Your scheme code might look something like this:

#include s2color
color p black
color p1 black
color p2 black
color p3 black
color p4 black
color p5 black
color p6 black
color p7 black
color p8 black
color p9 black
color p10 black
color p11 black
color p12 black
color p13 black
color p14 black
color p15 black

[Nick Cox]

You really don't need to define a scheme to do this. I suspect what Ting is missing most is the possibility of connect(L)

webuse grunfeld
xtset
twoway line mvalue year, ysc(log) c(L)

If the default colour is not black, then add lcolor(black).

An important side-effect of xtset is to restore the sort order you want for this kind of graph, should it have been lost somehow.

(I don't know why Maarten recommended c(J); knowing him, I'd suspect he remembered that the default c(l) is insufficient here, but remembered the wrong alternative.)

[Maarten Buis]

(I don't know why Maarten recommended c(J); knowing him, I'd suspect he remembered that the default c(l) is insufficient here, but remembered the wrong alternative.)

Nick's assumption is correct.

[Svend Juul]

I repeatedly made Maarten's mistake until I learned that instead of connect(L), I can write connect(ascending).

Svend

[Ting Liu]

Thanks a lot for all of you guys. "twoway line y x, ysc(log) c(ascending) lcolor(black)" really works now.