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F

factor()

factor(Expr1[, Var]) expression
factor(List1[,Var]) list
factor(Matrix1[,Var]) matrix

factor(Expr1) returns Expr1 factored with respect to all of its variables over a common denominator.

Expr1 is factored as much as possible toward linear rational factors without introducing new non-real subexpressions. This alternative is appropriate if you want factorization with respect to more than one variable.

factor(Expr1,Var) returns Expr1 factored with respect to variable Var.

Expr1 is factored as much as possible toward real factors that are linear in Var, even if it introduces irrational constants or subexpressions that are irrational in other variables.

The factors and their terms are sorted with Var as the main variable. Similar powers of Var are collected in each factor. Include Var if factorization is needed with respect to only that variable and you are willing to accept irrational expressions in any other variables to increase factorization with respect to Var. There might be some incidental factoring with respect to other variables.

For the Auto setting of the Auto or Approximate mode, including Var permits approximation with floating-point coefficients where irrational coefficients cannot be explicitly expressed concisely in terms of the built-in functions. Even when there is only one variable, including Var might yield more complete factorization.

Note: See also comDenom() for a fast way to achieve partial factoring when factor() is not fast enough or if it exhausts memory.

Note: See also cFactor() for factoring all the way to complex coefficients in pursuit of linear factors.

factor(rationalNumber) returns the rational number factored into primes. For composite numbers, the computing time grows exponentially with the number of digits in the second-largest factor. For example, factoring a 30-digit integer could take more than a day, and factoring a 100-digit number could take more than a century.

To stop a calculation manually,

Handheld: Hold down the c key and press · repeatedly.
Windows®: Hold down the F12 key and press Enter repeatedly.
Macintosh®: Hold down the F5 key and press Enter repeatedly.
iPad®: The app displays a prompt. You can continue waiting or cancel.

If you merely want to determine if a number is prime, use isPrime() instead. It is much faster, particularly if rationalNumber is not prime and if the second-largest factor has more than five digits.

FCdf()

FCdf(lowBound,upBound,dfNumer,dfDenom) number if lowBound and upBound are numbers, list if lowBound and upBound are lists

FCdf(lowBound,upBound,dfNumer,dfDenom) number if lowBound and upBound are numbers, list if lowBound and upBound are lists

Computes the F distribution probability between lowBound and upBound for the specified dfNumer (degrees of freedom) and dfDenom.

For P(X upBound), set lowBound = 0.

 

 

Fill

Fill Expr, matrixVar matrix

Replaces each element in variable matrixVar with Expr.

matrixVar must already exist.

Fill Expr, listVar list

Replaces each element in variable listVar with Expr.

listVar must already exist.

FiveNumSummary

FiveNumSummary X[,[Freq][,Category,Include]]

Provides an abbreviated version of the 1-variable statistics on list X. A summary of results is stored in the stat.results variable. (See here.)

X represents a list containing the data.

Freq is an optional list of frequency values. Each element in Freq specifies the frequency of occurrence for each corresponding X and Y data point. The default value is 1.

Category is a list of numeric category codes for the corresponding X data.

Include is a list of one or more of the category codes. Only those data items whose category code is included in this list are included in the calculation.

An empty (void) element in any of the lists X, Freq, or Category results in a void for the corresponding element of all those lists. For more information on empty elements, see here.

 

 

Output variable

Description

stat.MinX

Minimum of x values.

stat.Q1X

1st Quartile of x.

stat.MedianX

Median of x.

stat.Q3X

3rd Quartile of x.

stat.MaxX

Maximum of x values.

floor()

floor(Expr1) integer

Returns the greatest integer that is the argument. This function is identical to int().

The argument can be a real or a complex number.

floor(List1) list
floor(Matrix1) matrix

Returns a list or matrix of the floor of each element.

Note: See also ceiling() and int().

fMax()

fMax(Expr, Var) Boolean expression
fMax(Expr, Var,lowBound)

fMax(Expr, Var,lowBound,upBound)

fMax(Expr, Var) | lowBoundVarupBound

Returns a Boolean expression specifying candidate values of Var that maximize Expr or locate its least upper bound.

 

You can use the constraint (“|”) operator to restrict the solution interval and/or specify other constraints.

For the Approximate setting of the Auto or Approximate mode, fMax() iteratively searches for one approximate local maximum. This is often faster, particularly if you use the “|” operator to constrain the search to a relatively small interval that contains exactly one local maximum.

Note: See also fMin() and max().

fMin()

fMin(Expr, Var) Boolean expression

fMin(Expr, Var,lowBound)

fMin(Expr, Var,lowBound,upBound)

fMin(Expr, Var) | lowBoundVarupBound

Returns a Boolean expression specifying candidate values of Var that minimize Expr or locate its greatest lower bound.

You can use the constraint (“|”) operator to restrict the solution interval and/or specify other constraints.

For the Approximate setting of the Auto or Approximate mode, fMin() iteratively searches for one approximate local minimum. This is often faster, particularly if you use the “|” operator to constrain the search to a relatively small interval that contains exactly one local minimum.

Note: See also fMax() and min().

For

For Var, Low, High [, Step]
     Block
EndFor

Executes the statements in Block iteratively for each value of Var, from Low to High, in increments of Step.

Var must not be a system variable.

Step can be positive or negative. The default value is 1.

Block can be either a single statement or a series of statements separated with the “:” character.

Note for entering the example: For instructions on entering multi-line program and function definitions, refer to the Calculator section of your product guidebook.

format()

format(Expr[, formatString]) string

Returns Expr as a character string based on the format template.

Expr must simplify to a number.

formatString is a string and must be in the form: “F[n]”, “S[n]”, “E[n]”, “G[n][c]”, where [ ] indicate optional portions.

F[n]: Fixed format. n is the number of digits to display after the decimal point.

S[n]: Scientific format. n is the number of digits to display after the decimal point.

E[n]: Engineering format. n is the number of digits after the first significant digit. The exponent is adjusted to a multiple of three, and the decimal point is moved to the right by zero, one, or two digits.

G[n][c]: Same as fixed format but also separates digits to the left of the radix into groups of three. c specifies the group separator character and defaults to a comma. If c is a period, the radix will be shown as a comma.

[Rc]: Any of the above specifiers may be suffixed with the Rc radix flag, where c is a single character that specifies what to substitute for the radix point.

fPart()

fPart(Expr1) expression
fPart(List1) list
fPart(Matrix1) matrix

Returns the fractional part of the argument.

For a list or matrix, returns the fractional parts of the elements.

The argument can be a real or a complex number.

FPdf()

FPdf(XVal,dfNumer,dfDenom) number if XVal is a number, list if XVal is a list

Computes the F distribution probability at XVal for the specified dfNumer (degrees of freedom) and dfDenom.

 

 

freqTablelist()

freqTablelist(List1,freqIntegerList) list

Returns a list containing the elements from List1 expanded according to the frequencies in freqIntegerList. This function can be used for building a frequency table for the Data & Statistics application.

List1 can be any valid list.

freqIntegerList must have the same dimension as List1 and must contain non-negative integer elements only. Each element specifies the number of times the corresponding List1 element will be repeated in the result list. A value of zero excludes the corresponding List1 element.

Note: You can insert this function from the computer keyboard by typing freqTable@>list(...).

Empty (void) elements are ignored. For more information on empty elements, see here.

frequency()

frequency(List1,binsList) list

Returns a list containing counts of the elements in List1. The counts are based on ranges (bins) that you define in binsList.

If binsList is {b(1), b(2), …, b(n)}, the specified ranges are {?b(1), b(1)<?b(2),…,b(n-1)<?b(n), b(n)>?}. The resulting list is one element longer than binsList.

Each element of the result corresponds to the number of elements from List1 that are in the range of that bin. Expressed in terms of the countIf() function, the result is { countIf(list, ?b(1)), countIf(list, b(1)<?b(2)), …, countIf(list, b(n-1)<?b(n)), countIf(list, b(n)>?)}.

Elements of List1 that cannot be “placed in a bin” are ignored. Empty (void) elements are also ignored. For more information on empty elements, see here.

Within the Lists & Spreadsheet application, you can use a range of cells in place of both arguments.

Note: See also countIf(), here.

 

Explanation of result:

2 elements from Datalist are 2.5

4 elements from Datalist are >2.5 and 4.5

3 elements from Datalist are >4.5

The element “hello” is a string and cannot be placed in any of the defined bins.

FTest_2Samp

FTest_2Samp List1,List2[,Freq1[,Freq2[,Hypoth]]]

FTest_2Samp List1,List2[,Freq1[,Freq2[,Hypoth]]]

(Data list input)

FTest_2Samp sx1,n1,sx2,n2[,Hypoth]

FTest_2Samp sx1,n1,sx2,n2[,Hypoth]

(Summary stats input)

Performs a two-sample F test. A summary of results is stored in the stat.results variable. (See here.)

For Ha: σ1 > σ2, set Hypoth>0
For Ha: σ1 σ2 (default), set Hypoth =0
For Ha: σ1 < σ2, set Hypoth<0

For information on the effect of empty elements in a list, see Empty (Void) Elements, here.

 

Output variable

Description

stat.F

Calculated F statistic for the data sequence

stat.PVal

Smallest level of significance at which the null hypothesis can be rejected

stat.dfNumer

numerator degrees of freedom = n1-1

stat.dfDenom

denominator degrees of freedom = n2-1

stat.sx1, stat.sx2

Sample standard deviations of the data sequences in List 1 and List 2

stat.x1_bar
stat.x2_bar

Sample means of the data sequences in List 1 and List 2

stat.n1, stat.n2

Size of the samples

Func

Func
     Block
EndFunc

Template for creating a user-defined function.

Block can be a single statement, a series of statements separated with the “:” character, or a series of statements on separate lines. The function can use the Return instruction to return a specific result.

Note for entering the example: For instructions on entering multi-line program and function definitions, refer to the Calculator section of your product guidebook.

Define a piecewise function:

Result of graphing g(x)