Microsoft Word tutorial origin doc

mode”; you will use the “Basic mode” in this exercise. 
a. Click on “Analysis/Nonlinear curve fit“ from the drop-down menu; a “Nonlinear curve 
fitting” dialog box will appear. 
b. Move the cursor to the bottom of the dialog box until a double up/down arrow appears, 
then click and drag the bottom line of the dialog box down to its maximum vertical 
expansion. 
c. If either “Close” or “Accept” buttons appear, you are in the “Basic mode” dialog box; go to 
the next step. If a “Basic mode” button appears in the lower right corner of the dialog box, 
click on it to change to the “Basic mode” and go to the next step.
d. If the “Accept” button appears, click on it and proceed to the next step; if the “Close” 
button appears, proceed to the next step. 
3. Implementing a custom fitting algorithm. The above sequence should set the dialog box to the 
“Nonlinear curve fit:Select function mode”. Click on “New” and proceed as follows.
a. In new menu box, change: “Name” box to “LINFIT”, “Form” to “Expression” and “No. of 
Parameters” to 2. Origin will insert P1 and P2 for “Parameter names”. 
b. In the “Definitions” box, type P1+P2*X and click on “Save/Accept”. 
c. Click on “Start fitting” and then on “Active data set” in the new dialog box. 
d. A new dialog box will appear in which you must insert initial values for the fitting 
parameters, P1 and P2. Clear the dashes in the boxes and set “P1” to 0.01 (see Note 4 
below) and “P2” to 1 and click on “1 Iter”; numerical values of fitting parameters will 
appear. 
e. Be sure both boxes under “Vary ?” are checked. 
f. Click on “Done”; fitting parameters will be pasted onto the figure and entered below the 
figure. The procedure described above (III-B-2-b) can be used to paste these parameters 
into a script window. 
NOTES: 1. Both a and b were used in the fitting described in III-C above. It is sometimes desirable to fix 
one or more parameters. For example, the above fit can be forced through zero by clearing the “Vary ?” 
box (III-C-3-e) adjacent to the intercept, a, and inserting zero in the “Parameters” box. Try it. 
2. This feature is particularly useful when complicated expressions are being fit to complex data sets 
for the first time. 
3. For complex relationships with poorly defined initial estimates of fitting parameters, it usually is 
best to do approximate fits initially by clicking on “1 Iter” one or more times before asking for a full fit.
4. Never set the initial estimate of the intercept to zero (III-C-2-d). Values of some fitting parameters 
smaller than about 1 x 10
-15
interfere with procedures used to obtain numerical estimates of derivatives. 
IV. USE OF ORIGIN WITH A SPREAD-SHEET PROGRAM 
It is often necessary to use best-fit parameters to compute expected curves to be compared with 
experimental data or to extend the range of computed data beyond the range represented by the data 
set. This is easily done using a spreadsheet. The purpose of this section is to illustrate how a 
spreadsheet can be used in conjunction with Origin to recalculate and replot data with the data points 
superimposed on the best-fit line. 
A. Using 
Excel 
1. After doing a linear fit in Origin (Part III-B or III-C), look at the Results log and write down values of A 
(should be about A = 0.0204) and B (should be about B = 1.201). These are the slope and intercept 
of your data. 
2. Copy Column A of your origin worksheet, open an Excel worksheet and paste Column A from Origin 
to Column A of Excel. Type 2.75 after the last entry in Column A. You should have data in rows A1 
thru A10.
3. Highlight cells B1 thru B10 of the Excel worksheet. 

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4. With Excel cells B1 thru B10 highlighted, click in the Excel formula bar and type 
=0.0204+1.201*A1:A10. Then press CTRL/Shift/Enter simultaneously. Calculated best-fit values of 
Absorbance should appear in Cells B1 thru B10. 
5. Minimize the Excel worksheet for the time being. 
B. 
Plotting data using Origin 
The purpose here is to first plot data calculated using Excel as a line and then to superimpose the 
original data as discrete points on top of the line. We shall use the FORMATTED TEMPLATE (Part II-J) 
to plot a formatted figure.
1. Preparing the Origin worksheet 
a. Highlight and Copy data in Columns A and B of the ORG1_A worksheet and close the file. 
b. Open the FORMATTED TEMPLATE file and open a new worksheet. (See Part II-K-d). 
c. Paste data copied from the ORG1_A worksheet into Columns A and B of this worksheet (or type 
in the data from Table 1). Type the value 2.75 in Cell A-10 of the origin worksheet. 
d. Click “Column/Add New Column/OK” to add a new column. 
e. Deemphasize Origin, reemphasize the Excel worksheet and copy data in Column B of the Excel 
worksheet. 
f. 
Deemphasize the Excel worksheet, emphasize the Origin worksheet and paste the calculated 
data in Column C of the Origin worksheet. 
2. Plotting the line 
a. Highlight Column C in the Origin worksheet. 
b. Bring the formatted graph to the forefront and Click “Graph/Add plot to layer/Line/OK”; a line plot 
should appear. 
3. Adding scatter points 
a. Bring the worksheet to the forefront and highlight Column B. 
b. Bring the formatted graph to the forefront and Click “Graph/Add plot to layer/Scatter/OK”; Data 
points should be superimposed on the line plot. 
c. Change the X/Y scales so that the line and points fall inside the axes. (See Part II-D-1 and 2). 
d. Change points to open symbols to visualize that points are superimposed on the best-fit line. 
(See Part II-H.) 
e. Save using a suitable file name and print. 
V. NONLINEAR DATA SET (GAUSSIAN FUNCTION)
An attractive feature of Origin and other data analysis programs is that they permit fits of user-
selected models to nonlinear data sets. This section illustrates the use of Origin to fit a Gaussian model to 
a data set (Table 1, Columns F and G) similar to that obtained for paper clips in the laboratory. 
A. Mathematical model
The data are expected to conform to a model of the form 
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