Family Regression

        This program will use standard 
linear regression techniques and
linearizing tranformations to fit data
from a .DO file with the following
models:


        Y = A+B*X        Linear

        Y = A+B*LOG(X)   Logarithmic

        Y = A*EXP(B*X)   Exponetial

        Y = A*X^B        Power

The values for A and B are returned 
with their associated correlation coef-
ficient. Next the data is plotted on 
the LCD, followed by whichever fit the
user selected.

        After loading the program into 
the computer, one must store the data 
to be fit into a .DO file.  Select the 
TEXT mode and enter the data as pairs 
of independent and dependent values, in
the following way:

1.1,2.8
2,3.87
2.92,5.02
3.77,6.091
4.72,7.21

Once the data is entered then exit the 
TEXT select the FAMREG program. The 
following will be displayed on the LCD:

           FAMILY REGRESSION
        THIS PROGRAM WILL DO LINEAR(N),
EXPONENTIAL(E), LOGARITHMIC(L), AND/OR
POWER(P) FITS TO DATA IN A .DO FILE,
PRINT THE FACTORS, AND PLOT BOTH DATA
AND FITS.

At the bottom of the LCD will be the 
following question:

WHICH .DO FILE IS TO BE FIT?

The user will then need to enter the 
name of the in which the data stored. 
This question will disappear and be 
replaced with the following:

WHICH FITS (ENTER LETTER)?

The user will then the letter assoc-
iated with the model desired. For 
instance, if one wanted only to do an 
exponential fit, then only an E is 
entered. However, if a linear and a 
exponential fit is desired then either 
NE or EN would be entered.  Once the 
types of fits are selected, then the 
LCD is cleared and the word WORKING is 
displayed in the center.  After a 
moment A, B and the correlation 
coefficient will be displayed for a 
particular fit. For instance, a linear
fit of the above example would return 
the following:


    LINEAR FIT -> Y = B*X+A

  A = 1.44247
  B = 1.22527

     CORR. COEFF. = .99929
     <PRESS ANY KEY TO CONTINUE>

Each selected fit will be displayed 
separately.  After all the fits have 
been displayed, then the LCD will be 
cleared and the data poits plotted.  
Next a selected fit will be plotted 
over the data. When that fit is plot-
ted, an abbreivation of the type of fit
(i.e. LIN., EXP., LOG. or POW.) will 
appear on the left side to the LCD. 
When the user is ready to plot the next
fit, one need only hit any key. If 
there are no more fits then END appear 
left side.

        The checksum=371,870. This 
program must have LINE.CO from DL7 to 
run.

        One last note, with a little 
thought, one could use lines 900-1380 
to plot most any X-Y graph one might 
want.

          Hope you find this useful,
          Randy Kays [74766,3553]