I need some help making a graph, I know how to do a basic graph, but My data has 2 X variables and the same Y variable. How can I graph this? I Know I can graph the same X variable with different Y variables, but I cant seem to do it no matter which way I do it.

Here is the data I am graphing:

0	0
.509	2
.544	5
.568	6
.585	8
.599	10
.613	12
.621	14
.630	16
.639	18
.645	20

0	0
1.683	2
1.732	5
1.766	6
1.795	8
1.822	10
1.845	12
1.866	14
1.886	16
1.908	18
1.924	20

As you see, the Y variable is the same, and I cant get the 2 to show up on the same graph. I know it works the other way, but the professor wants it done this way to make the graph display the way its supposed to.

Do you have access to Matlab?

Quote: Originally Posted by Nerdz 0 0 0 1.683 0.509 2 1.732 0.544 5 1.766 0.568 6 1.795 0.585 8 1.822 0.599 10 1.845 0.613 12 1.866 0.621 14 1.886 0.63 16 1.908 0.639 18 1.924 0.645 20

Was this what you were looking for? Arrange your data like I have above, then you should get what you need.

Just arrange your 2 x info before your y info in columns and make a scatter point chart. Scatter point charts are your friend

boardboyd, that graph is wrong. Check it against the data and you should see what I'm talking about.

The yellow line appears to be correct but the red one has the 0 to .645 as a function of 0 to 1.924. And since the yellow line is so horrid I think that you'd want the integers as the x axis and the other data as the y axis. That is easy, just put the integers as the first column and then the other two as the next two columns and select the range as the data and you know the rest

ADD: Except those 0 points really throw the chart off, that is if this should be linear.

Oops should be something like this I guess:

You need to have XY above XY like:

0	0
1.68	2
1.73	5
1.77	6
1.8	8
1.82	10
1.85	12
1.87	14
1.89	16
1.91	18
1.92	20
0	0
0.51	2
0.54	5
0.57	6
0.59	8
0.6	10
0.61	12
0.62	14
0.63	16
0.64	18
0.65	20

And select the whole 2 columns when making the chart.
**edit forgot to mention that you should make your's a lined scatterpoint instead of just a straight scatterpoint. This only makes one data series though, this is easier in excel.

I just looked into the OOo Calc FAQ and it doesn't do multiple X data series atm. So my above is an apparent workaround. Unfortunately you cannot make 2 separate lines, if you try it will make one single line. This is one area Excel excels at.

Quote: Originally Posted by boardboyd Oops should be something like this I guess: You need to have XY above XY like: 0 0 1.68 2 1.73 5 1.77 6 1.8 8 1.82 10 1.85 12 1.87 14 1.89 16 1.91 18 1.92 20 0 0 0.51 2 0.54 5 0.57 6 0.59 8 0.6 10 0.61 12 0.62 14 0.63 16 0.64 18 0.65 20 And select the whole 2 columns when making the chart. **edit forgot to mention that you should make your's a lined scatterpoint instead of just a straight scatterpoint. This only makes one data series though, this is easier in excel.

OMGWTFBBQ111! You had it wrong on your first attempt, but this is how exactly I need it! Thank you a lot!! +rep! I dont mind doing the line manually either, I had to do this a lot for my physics class.

Quote: Originally Posted by 4x0n boardboyd, that graph is wrong. Check it against the data and you should see what I'm talking about. The yellow line appears to be correct but the red one has the 0 to .645 as a function of 0 to 1.924. And since the yellow line is so horrid I think that you'd want the integers as the x axis and the other data as the y axis. That is easy, just put the integers as the first column and then the other two as the next two columns and select the range as the data and you know the rest ADD: Except those 0 points really throw the chart off, that is if this should be linear.

You are correct also. Nope, 0,0 has to be there. This is a diode Characteristic chart, which if you know, is supposed to "climb" up at around .7V, but mine is OK, since there seems to be a 20% tolerance in diodes. +rep for helping too.

Oh My God, you guys make me feel so stupid every time I read your threads. On the other hand, I love watching as you collaborate scientifically and work as a team to find a solution to your questions. THIS is PCApex at it's Finest. Sweet!!!

Quote: Originally Posted by Nerdz You are correct also. Nope, 0,0 has to be there. This is a diode Characteristic chart, which if you know, is supposed to "climb" up at around .7V, but mine is OK, since there seems to be a 20% tolerance in diodes. +rep for helping too.

But you should get yourself Matlab or Octave, Octave is free and linux compatible but both are excellent at graphing or you could try GNUplot.

Quote: Originally Posted by 4x0n But you should get yourself Matlab or Octave, Octave is free and linux compatible but both are excellent at graphing or you could try GNUplot.

Can oOo Graph Equations? Thanks!

Quote: Originally Posted by Nerdz Can oOo Graph Equations? Thanks!

Not as easily as Octave + Gnuplot or Matlab. You have to do everything on a spreadsheet i.e.
set your limits for your x or y and increment them by some increment that you want, then run your formula for your other variable to plot. It's much easier with Matlab or octave+gnuplot, I think Maple will do it as well, or Maple might just do physics stuff.

Man it's been like 5 years since I used Matlab.

Matlab is mainly for solving equations and problems (and other things) numerically while Maple and Mathematica can integrate, solve equations etc. without inputting numbers into the equations.