Chromatography Forum

i find excel really difficult to use for scientific graph. i need another program that does trend lines / calibration curves ect..
What is a good application that i can use in substiture of excel?

There are several, but none are any easier to use than Excel (IMHO).

You might try Origin.

Excel is relatively most simpler to many of us. However still many find trouble with excel trendline feature. For simple regression you need not to have commercial product and if you google you will find many. Linear regression in most staistical packages is also very simple (however simpler is subjective). Try different freewares and see which you find useful.

A good link may be this: http://statistiksoftware.com/free_software.html

Excel's help files are pretty useful, but the more advanced stats are a chore. Read up on Array functions in general if you want a linear regression with additional statistics, then look up the linest function.

The general trick to array functions is that you have to select an appropriate range of output cells and write the function as you normally would in the active cell. To get the thing to work in the range, you have to close the edit on the active cell by hitting ctrl-shift-enter instead of just enter.

As with all of these apps, RTM.

I think that everyone does agree with the fact that excel is maybe not the simplest program for regressions, but its almost the easiest.

Maybe you can post your specific problem with the regression, calibration, etc... and we can help you to develop a worksheet thats easy to use?

Bart

I have used SigmaPlot. It is good, but I doubt it's worth buying if you don't use it regularly.
For some things it is easier to use than Excel, for others not at all (I sometimes ended up preparing the datasets in excel or SPSS just to bring them in a convenient form for SigmaPlot)

SPSS, a statistics software, can be easier, too, for those purposes. I mention this because it might be that some colleague in the building uses this regularly and has it installed on his computer which you could use... This would have the added advantage that he already would know how to use it.

If this is not the case, go with jitender's recomendations!

I found R very usefull, but I doubt it's easier than Excell.
If you want to use R, download the RCmdr package, it will become a lot easier.

GL

Bart

I also find R-language very good and its a kind of my favorite. However, I use it for some difficult computaion work. Its command line interface makes it difficult for many people especially those always worked with graphical interface programs. I have not loaded Rcmdr ever. It may be useful.

Indeed the command line is a bit confusing when you used to work with graphical interfaces. But once you learn to work with it, and you can make your own scripts life become much easier.

@jitender:
Here is some information about the RCmdr:
http://socserv.mcmaster.ca/jfox/Misc/Rcmdr/

I have tried it to see what it does, and in the beginning I used it as a learning tool: For everything it does it write down the commands used.

Best regards

Bart