HP 39gII

Statistics 2Var app 91
To define your
own fit
1. Display the Symbolic view.
2. Highlight the Fit expression (Fit1, etc.) for the
desired data set.
3. Type in an expression and press
E. The
independent variable must be X, and the expression
must not contain any unknown variables.
Example: .
Computed statistics
When you press , there are three sets of statistics
available. By default, the statistics involving both the
independent and dependent columns are shown. Press
to see the statistics involving just the independent
column or to display the statistics derived from the
Logistic Fits to a logistic curve,
where L is the saturation value
for growth. You can store a
positive real value in L, or—if
L=0—let L be computed
automatically.
Quadratic Fits to a quadratic curve,
y = ax
2
+bx+c. Needs at least
three points.
Cubic Fits to a cubic polynomial,
Quartic Fits to a quartic polynomial,
Trigonometric Fits to a trigonometric curve,
. Needs
at least three points.
User Defined Define your own expression (in
the Symbolic view.)
Fit model Meaning (Continued)
y
L
1 ae
bx–()
+
--------------------------=
yax
3
b
2
xcxd+++=
yax
4
bx
3
cx
2
dx e++++=
ya bxc+()sin⋅ d+=
1.5 xcos× 0.3 xsin×+