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E

e^()

e^(Expr1) expression

Returns e raised to the Expr1 power.

Note: See also e exponent template, here.

Note: Pressing u to display e^( is different from pressing the character E on the keyboard.

You can enter a complex number in reiθ polar form. However, use this form in Radian angle mode only; it causes a Domain error in Degree or Gradian angle mode.

e^(List1) list

Returns e raised to the power of each element in List1.

e^(squareMatrix1) squareMatrix

Returns the matrix exponential of squareMatrix1. This is not the same as calculating e raised to the power of each element. For information about the calculation method, refer to cos().

squareMatrix1 must be diagonalizable. The result always contains floating-point numbers.

eff()

eff(nominalRate,CpY) value

Financial function that converts the nominal interest rate nominalRate to an annual effective rate, given CpY as the number of compounding periods per year.

nominalRate must be a real number, and CpY must be a real number > 0.

Note: See also nom(), here.

eigVc()

eigVc(squareMatrix) matrix

Returns a matrix containing the eigenvectors for a real or complex squareMatrix, where each column in the result corresponds to an eigenvalue. Note that an eigenvector is not unique; it may be scaled by any constant factor. The eigenvectors are normalized, meaning that:

if  V = [x1, x2, … , xn]

then x12 + x22 + … + xn2 = 1

squareMatrix is first balanced with similarity transformations until the row and column norms are as close to the same value as possible. The squareMatrix is then reduced to upper Hessenberg form and the eigenvectors are computed via a Schur factorization.

In Rectangular Complex Format:

To see the entire result,
press 5 and then use 7 and 8 to move the cursor.

eigVl()

eigVl(squareMatrix) list

Returns a list of the eigenvalues of a real or complex squareMatrix.

squareMatrix is first balanced with similarity transformations until the row and column norms are as close to the same value as possible. The squareMatrix is then reduced to upper Hessenberg form and the eigenvalues are computed from the upper Hessenberg matrix.

In Rectangular complex format mode:

To see the entire result,
press 5 and then use 7 and 8 to move the cursor.

Else

 

 

ElseIf

If BooleanExpr1 Then
     Block1
ElseIf BooleanExpr2 Then
     Block2

ElseIf BooleanExprN Then
     BlockN
EndIf

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

 

EndFor

 

 

EndFunc

 

 

EndIf

 

 

EndLoop

 

 

EndPrgm

 

 

EndTry

 

 

EndWhile

 

 

euler ()

euler(Expr, Var, depVar, {Var0, VarMax}, depVar0, VarStep [, eulerStep]) matrix

euler(SystemOfExpr, Var, ListOfDepVars, {Var0, VarMax},      ListOfDepVars0, VarStep [, eulerStep]) matrix

euler(ListOfExpr, Var, ListOfDepVars, {Var0, VarMax}ListOfDepVars0, VarStep [, eulerStep]) matrix

Uses the Euler method to solve the system

with depVar(Var0)=depVar0 on the interval [Var0,VarMax]. Returns a matrix whose first row defines the Var output values and whose second row defines the value of the first solution component at the corresponding Var values, and so on.

Expr is the right-hand side that defines the ordinary differential equation (ODE).

SystemOfExpr is the system of right-hand sides that define the system of ODEs (corresponds to order of dependent variables in ListOfDepVars).

ListOfExpr is a list of right-hand sides that define the system of ODEs (corresponds to the order of dependent variables in ListOfDepVars).

Var is the independent variable.

ListOfDepVars is a list of dependent variables.

{Var0, VarMax} is a two-element list that tells the function to integrate from Var0 to VarMax.

ListOfDepVars0 is a list of initial values for dependent variables.

VarStep is a nonzero number such that sign(VarStep) = sign(VarMaxVar0) and solutions are returned at Var0+iVarStep for all i=0,1,2,… such that Var0+iVarStep is in [var0,VarMax] (there may not be a solution value at VarMax).

eulerStep is a positive integer (defaults to 1) that defines the number of euler steps between output values. The actual step size used by the euler method is VarStep  eulerStep.

Differential equation:
y'=0.001*y*(100-y) and y(0)=10

To see the entire result,
press 5 and then use 7 and 8 to move the cursor.

Compare above result with CAS exact solution obtained using deSolve() and seqGen():




System of equations:

with y1(0)=2 and y2(0)=5

eval () 

eval(Expr) string

eval() is valid only in the TI‑Innovator™ Hub Command argument of programming commands Get, GetStr, and Send. The software evaluates expression Expr and replaces the eval() statement with the result as a character string.

The argument Expr must simplify to a real number.

Set the blue element of the RGB LED to half intensity.

Reset the blue element to OFF.

eval() argument must simplify to a real number.

Program to fade-in the red element

Execute the program.

Although eval() does not display its result, you can view the resulting Hub command string after executing the command by inspecting any of the following special variables.

iostr.SendAns
iostr.GetAns
iostr.GetStrAns

Note: See also Get (here), GetStr (here), and Send (here).

exact()

exact(Expr1 [, Tolerance]) expression
exact(List1 [, Tolerance]) list
exact(Matrix1 [, Tolerance]) matrix

Uses Exact mode arithmetic to return, when possible, the rational-number equivalent of the argument.

Tolerance specifies the tolerance for the conversion; the default is 0 (zero).

Exit

Exit

Exits the current For, While, or Loop block.

Exit is not allowed outside the three looping structures (For, While, or Loop).

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

Function listing:

exp

Exprexp

Represents Expr in terms of the natural exponential e. This is a display conversion operator. It can be used only at the end of the entry line.

Note: You can insert this operator from the computer keyboard by typing @>exp.

exp()

exp(Expr1) expression

Returns e raised to the Expr1 power.

Note: See also e exponent template, here.

You can enter a complex number in reiθ polar form. However, use this form in Radian angle mode only; it causes a Domain error in Degree or Gradian angle mode.

exp(List1) list

Returns e raised to the power of each element in List1.

exp(squareMatrix1) squareMatrix

Returns the matrix exponential of squareMatrix1. This is not the same as calculating e raised to the power of each element. For information about the calculation method, refer to cos().

squareMatrix1 must be diagonalizable. The result always contains floating-point numbers.

explist()

explist(Expr,Var) list

Examines Expr for equations that are separated by the word “or,” and returns a list containing the right-hand sides of the equations of the form Var=Expr. This gives you an easy way to extract some solution values embedded in the results of the solve(), cSolve(), fMin(), and fMax() functions.

Note: explist() is not necessary with the zeros() and cZeros() functions because they return a list of solution values directly.

You can insert this function from the keyboard by typing exp@>list(...).

expand()

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

expand(Expr1) returns Expr1 expanded with respect to all its variables. The expansion is polynomial expansion for polynomials and partial fraction expansion for rational expressions.

The goal of expand() is to transform Expr1 into a sum and/or difference of simple terms. In contrast, the goal of factor() is to transform Expr1 into a product and/or quotient of simple factors.

expand(Expr1,Var) returns Expr1 expanded with respect to Var. Similar powers of Var are collected. The terms and their factors are sorted with Var as the main variable. There might be some incidental factoring or expansion of the collected coefficients. Compared to omitting Var, this often saves time, memory, and screen space, while making the expression more comprehensible.

Even when there is only one variable, using Var might make the denominator factorization used for partial fraction expansion more complete.

Hint: For rational expressions, propFrac() is a faster but less extreme alternative to expand().

Note: See also comDenom() for an expanded numerator over an expanded denominator.

expand(Expr1,[Var]) also distributes logarithms and fractional powers regardless of Var. For increased distribution of logarithms and fractional powers, inequality constraints might be necessary to guarantee that some factors are nonnegative.

expand(Expr1, [Var]) also distributes absolute values, sign(), and exponentials, regardless of Var.

Note: See also tExpand() for trigonometric angle-sum and multiple-angle expansion.

expr()

expr(String) expression

Returns the character string contained in String as an expression and immediately executes it.

ExpReg

ExpReg X, Y [, [Freq] [, Category, Include]]

Computes the exponential regression y = a(b)x on lists X and Y with frequency Freq. A summary of results is stored in the stat.results variable. (See here.)

All the lists must have equal dimension except for Include.

X and Y are lists of independent and dependent variables.

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. All elements must be integers 0.

Category is a list of category codes for the corresponding X and Y 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.

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

 

Output variable

Description

stat.RegEqn

Regression equation: a(b)x

stat.a, stat.b

Regression coefficients

stat.r2

Coefficient of linear determination for transformed data

stat.r

Correlation coefficient for transformed data (x, ln(y))

stat.Resid

Residuals associated with the exponential model

stat.ResidTrans

Residuals associated with linear fit of transformed data

stat.XReg

List of data points in the modified X List actually used in the regression based on restrictions of Freq, Category List, and Include Categories

stat.YReg

List of data points in the modified Y List actually used in the regression based on restrictions of Freq, Category List, and Include Categories

stat.FreqReg

List of frequencies corresponding to stat.XReg and stat.YReg