adding marker points

[Kara]

Hi I am trying to make a chart of patients lab vaules...basically for each
patient I have there date and corresponding lab value making this line graph
is easy....what I want to do is a vertical line at a particular date that
corresponds to a treatment date...this date more than likely has no lab value
that corresponds to it.... I think I could do individually by just drawing a
marker in on the existing line graph ...but with multiple people and multiple
treatment dates for each patient this could become lengthy ...is there some
trick I am missing?

 

[Del Cotter]

I am trying to make a chart of patients lab vaules...basically for each
patient I have there date and corresponding lab value making this line graph
is easy....what I want to do is a vertical line at a particular date that
corresponds to a treatment date...

Create your chart as a Line chart type, then make sure the X axis is a
Time-scale axis (ask for instructions if you don't know how to do this,
making sure to say which version of Excel you use)

Now create a block of data separate from your lab data, like this:

Vertical line
[Date] 0
[Date] [maximum on chart]

The two dates are the same, the date that you want to put the line
running from zero to the top of the chart. Now copy this block and Paste
Special into the line chart, where it should appear as a new line series
in the wrong place. Select the series and change its Chart Type to XY
(Scatter), which should cause it to appear in the correct place on the
line chart, as a vertical line.

Alternatively, simply create it in with your lab data, with dates in the
same column but the y value in a column separate from the lab values,
like this:

Lab Treatment
13/07/2008 0.887
14/07/2008 0.533
15/07/2008 0.694
16/07/2008 0.921
17/07/2008 0.256
18/07/2008 0.921
19/07/2008 0.866

Then when you've made your line chart, give the "Treatment" series a Y
error bar of 100% Minus, which will create a line that drops down to the
bottom of the chart.

 

[Jon Peltier]

Add lines to a chart:
http://peltiertech.com/Excel/Charts/AddLine.html

- Jon