user manual
Chapter 2: Main Application  86
 u binomialCDf [Action][Distribution/Inv.Dist][Discrete][binomialCDf]
Function: Returns the cumulative probability in a binomial distribution that the success will occur between 
specified lower value and upper value. 
Syntax: binomialCDf(lower value, upper value, numtrial value, 
pos  [ ) ]
Calculation Result Output:  
prob 
Example: To determine the binomial cumulative probability when lower value 
= 2, upper value = 5, numtrial value = 3, pos  = 0.63 
 u  invBinomialCDf [Action][Distribution/Inv.Dist][Inverse][invBinomialCDf]
Function: Returns the minimum number of trials of a binomial cumulative probability distribution for specified 
values.
Syntax: invBinomialCDf( 
prob , numtrial value, pos  [ ) ] 
Calculation Result Output:  
x Inv, ½ x Inv
Important!
When executing the invBinomialCDf, invPoissonCDf, invGeoCDf, or 
invHypergeoCDf function, the ClassPad uses the specified prob  value and 
the value that is one less the prob  value minimum number of significant digits 
(½ 
prob  value) to calculate minimum number of trials values. The results 
are assigned to the system variables 
xInv  (calculation result using prob ) 
and ½ xInv  (calculation result using ½ prob ). The function always returns the 
 xInv  value only. However, when the xInv  and ½ xInv  values are different, the 
warning message shown nearby appears showing both values. 
The calculation results of the function are integers. Accuracy may be reduced 
when the first argument has 10 or more digits. Note that even a slight difference in calculation accuracy 
affects calculation results. If a warning message appears, check the displayed values.
Example: To determine the minimum number of trials when 
prob = 0.609, 
numtrial value = 5, pos = 0.63 
 u poissonPDf [Action][Distribution/Inv.Dist][Discrete][poissonPDf]
Function: Returns the probability in a Poisson distribution that the success will occur on a specified trial.
Syntax: poissonPDf( 
x ,  [ ) ]
Calculation Result Output:  
prob 
Example: To determine the Poisson probability when x  = 10,  = 6 
 u poissonCDf [Action][Distribution/Inv.Dist][Discrete][poissonCDf]
Function: Returns the cumulative probability in a Poisson distribution that the success will occur between 
specified lower value and upper value. 
Syntax: poissonCDf(lower value, upper value,  [ ) ]
Calculation Result Output:  
prob 
Example: To determine the Poisson cumulative probability when lower 
value = 2, upper value = 3,  = 2.26 
 u invPoissonCDf [Action][Distribution/Inv.Dist][Inverse][invPoissonCDf]
Function: Returns the minimum number of trials of a Poisson cumulative probability distribution for specified 
values.
Syntax: invPoissonCDf( 
prob ,  [ ) ] 
Calculation Result Output:  x Inv, ½ x Inv










