A Microsoft Office (Excel, Word) forum. OfficeFrustration

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » OfficeFrustration forum » Microsoft Excel » Charts and Charting
Site Map Home Register Authors List Search Today's Posts Mark Forums Read  

manipulating x-axis and calculating derived values from data



 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old May 22nd, 2011, 03:37 PM
jglasermd jglasermd is offline
Member
 
First recorded activity by OfficeFrustration: May 2011
Posts: 3
Default manipulating x-axis and calculating derived values from data

Hi all:

I have a couple of things I have been trying to do with Excel, to no avail. I am developing some Excel sheets and charts to use for nuclear medicine imaging test results. Here are my problems:

1. the test in question uses images taken at various time intervals (in minutes): 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 105, 120. As you can see, the first several intervals are in increments of 5, while the later values are in increments of 15. These tests are graphed with the above times on the x-axis and activity (in imaging count rates) on the y-axis. I have been trying to fix the x-axis so that the spacing of the data points and the slopes between them are accurate even using this irregular interval; until now all the data points look like they are 5 minutes apart and this is not true. If I try to use empty cells to fill dummy points, the curve keeps dipping back to the x-axis assuming the value is zero.

2. Once the above is figured out, I am also trying to take the calculated value of 1/2 of the maximum y-axis value, and automatically generate a value for the corresponding x-axis coordinate. this corresponds to the time where the activity present at the beginning of the test has decreased by half. This has medical significance to us. At the present time, it is measured by hand and is laborious.

Please help!
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 10:51 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 OfficeFrustration.
The comments are property of their posters.