kUsing Distribution Graphs in a Program

Special commands are used to draw distribution graphs in a program.

• To draw a normal cumulative distribution graph

DrawDistNorm <Lower>, <Upper> [,σ, ]

Population mean*1

Population standard deviation*1

Data upper limit

Data lower limit

*1 This can be omitted. Omitting these items performs the calculation using  = 1 and  = 0.

 

1

 

∫

Upper

–

(x – μ)2

 

 

Lower – μ

ZUp =

Upper – μ

p =

 

 

2

dx

 

 

 

 

 

e

2σ

 

ZLow =

 

 

 

 

 

 

 

 

σ

 

 

 

 

 

σ

 

2πσ

Lower

 

 

 

 

 

 

 

 

 

 

 

 

 

 

•Executing DrawDistNorm performs the above calculation in accordance with the specified conditions and draws the graph. At this time the ZLow < x < ZUp region on the graph is filled in.

•At the same time, the p, ZLow, and ZUp calculation result values are assigned respectively to variables p, ZLow, and ZUp, and p is assigned to Ans.

•To draw a Student-tcumulative distribution graph

DrawDistT <Lower>, <Upper>, <df>

Degree of freedom

Data upper limit

Data lower limit

–df + 1

Upper

Γ

df + 1

 

1 +

x2

 

2

 

 

 

 

2

 

 

df

 

 

 

 

p = ∫Lower

 

 

 

⋅

 

 

 

dx

tLow = Lower

tUp = Upper

 

 

 

 

 

 

 

 

 

 

df

 

 

 

 

Γ

 

 

π ⋅ df

 

 

2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

•Executing DrawDistT performs the above calculation in accordance with the specified conditions and draws the graph. At this time the Lower < x < Upper region on the graph is filled in.

•At the same time, the p calculation result value and the Lower and Upper input values are assigned respectively to variables p, tLow, and tUp, and p is assigned to Ans.

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