Computed Statistics - HP 39g+ User Manual

To define your
own fit

Computed statistics

One-variable
Statistics aplet
Fit model
Quadratic
Cubic
Logistic
User
Defined
1. In Numeric view, make sure
2. Display the Symbolic view.
3. Highlight the Fit expression (Fit1, etc.) for the
desired data set.
4. Type in an expression and press
The independent variable must be X, and the
expression must not contain any unknown variables.
×
1.5
Example:
This automatically changes the Fit type (S1FIT, etc.) in
the Symbolic Setup view to User Defined.
Statistic
NΣ
TOTΣ
Meaning (Continued)
Fits to a quadratic curve,
2
y = ax +bx+c. Needs at least three
points.
Fits to a cubic curve,
3 2
y = ax +bx +cx+d. Needs at least
four points.
Fits to a logistic curve,
L
------------------------- -
y =
– ( )
bx
1 + ae
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.
Define your own expression (in
Symbolic view.)
×
cos x + 0.3 sin x
.
Definition
Number of data points.
Sum of data values (with their
frequencies).
,
is set.
.
8-13