Difference between revisions of "Math functions"
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[[Category:Analytica User Guide]] | [[Category:Analytica User Guide]] | ||
[[Category: Math Functions]] | [[Category: Math Functions]] | ||
− | <breadcrumbs>Analytica User Guide > | + | <breadcrumbs>Analytica User Guide > Expressions > {{PAGENAME}}</breadcrumbs> |
− | + | {{ReleaseBar}} | |
These functions can be accessed from the '''Math '''library from the [[Definition menu]]. | These functions can be accessed from the '''Math '''library from the [[Definition menu]]. | ||
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:<code>Ceil(Pi, 4) → 3.1416</code> | :<code>Ceil(Pi, 4) → 3.1416</code> | ||
:<code>Ceil(-12345, -2) → -12300</code> | :<code>Ceil(-12345, -2) → -12300</code> | ||
+ | |||
+ | '''Ceil(x, ,dateUnit)''': Rounds a date-time «x» up to the indicated «dateUnit», where «dateUnit» can be 'Y', 'Q', 'M', 'D', 'h', 'm', or 's' (year, quarter, month, day, hour, minute, second). | ||
+ | :<code>Ceil(26-July-2017, dateUnit:'Y') → 1-Jan-2018</code> | ||
+ | :<code>Ceil(26-July-2017, dateUnit:'M') → 1-Aug-2017</code> | ||
+ | :<code>Ceil(26-July-2017, dateUnit:'D') → 26-July-2017</code> | ||
'''Floor(x)''': Returns the largest integer that is smaller than or equal to «x». See also [[Floor]](). | '''Floor(x)''': Returns the largest integer that is smaller than or equal to «x». See also [[Floor]](). | ||
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:<code>Floor(Pi, 4) → 3.1415</code> | :<code>Floor(Pi, 4) → 3.1415</code> | ||
:<code>Floor(-12345, -2) → -12400</code> | :<code>Floor(-12345, -2) → -12400</code> | ||
+ | |||
+ | '''Floor(x, ,dateUnit)''': Rounds a date-time «x» down to the indicated «dateUnit», where «dateUnit» can be 'Y', 'Q', 'M', 'D', 'h', 'm', or 's' (year, quarter, month, day, hour, minute, second). | ||
+ | :<code>Floor(26-July-2017, dateUnit:'Y') → 1-Jan-2017</code> | ||
+ | :<code>Floor(26-July-2017, dateUnit:'M') → 1-July-2017</code> | ||
+ | :<code>Floor(26-July-2017, dateUnit:'D') → 26-July-2017</code> | ||
'''Round(x)''': Returns the value of «x» rounded to the nearest integer. See also [[Round]](). | '''Round(x)''': Returns the value of «x» rounded to the nearest integer. See also [[Round]](). | ||
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:<code>Factorial(0) → 1</code> | :<code>Factorial(0) → 1</code> | ||
If «x» is not an integer, it rounds «x» to the nearest integer before taking the factorial. | If «x» is not an integer, it rounds «x» to the nearest integer before taking the factorial. | ||
+ | |||
+ | '''Logit(p)''': The inverse of the [[Sigmoid]] function, is defined for <code>0 < p < 1</code> and is equal to <code>[[Ln]](p / (1-p))</code>. See alse [[Logit]](). | ||
+ | :<code>Logit(0.5) →0</code> | ||
+ | :<code>Logit(0.25) → -1.099</code> | ||
+ | |||
+ | {{Release|5.0||'''ProductLog(z)''': Returns the value for x that solves <code>z {{=}} x * [[Exp]](x)</code>. It is also known as the Lambert W function. It is real-valued for a real-valued parameter with <code>z ≥ -[[Exp]](-1)</code>. It is also defined for all complex numbers. For real-valued '''z''' with <code>z<-[[Exp]](-1)</code>, a complex result is returned only when [[EnableComplexNumbers]] is on, and in which case, the so called ''first branch'' or ''upper branch'' (<math>W_0(z)</math>) is returned. See also [[ProductLog]](). | ||
+ | :<code>ProductLog(0) → 0</code> | ||
+ | :<code>ProductLog(100) → 3.386</code> | ||
+ | ::<code> 3.386 * Exp(3.386) → 100</code> | ||
+ | }} | ||
+ | |||
+ | '''Sigmoid(x)''': The sigmoid function is also called the logistic function, the expit function, or the inverse logit function. It serves as a continuous approximation to the step function <code>(x>=0)</code>. It approaches 0 as '''x''' approaches <code>-Inf</code>, approaches 1 as x approaches <code>Inf</code> and is 1/2 at x=0. It is equal to <code>1/(1+[[Exp]](-x))</code>. See also [[Sigmoid]](). | ||
+ | :<code>Sigmoid(0) → 0.5</code> | ||
+ | :<code>Sigmoid(1) → 0.7311</code> | ||
'''Cos(x), Sin(x), Tan(x)''': Return the cosine, sine, and tangent of «x», «x» assumed in degrees. See also [[Cos]](x), [[Sin]](x), [[Tan]](x). | '''Cos(x), Sin(x), Tan(x)''': Return the cosine, sine, and tangent of «x», «x» assumed in degrees. See also [[Cos]](x), [[Sin]](x), [[Tan]](x). | ||
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* [[Numbers]] | * [[Numbers]] | ||
* [[Number formats]] | * [[Number formats]] | ||
+ | * [[Text, Date, Math, and Financial Functions]] | ||
* [[Advanced math functions]] | * [[Advanced math functions]] | ||
* [[Complex number functions]] | * [[Complex number functions]] |
Latest revision as of 17:48, 4 August 2017
Release: |
4.6 • 5.0 • 5.1 • 5.2 • 5.3 • 5.4 • 6.0 • 6.1 • 6.2 • 6.3 • 6.4 • 6.5 |
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These functions can be accessed from the Math library from the Definition menu.
Abs(x): Returns the absolute value of «x». When «x» is complex, returns the magnitude, see Complex number functions. See also Abs().
Abs(180) → 180
Abs(-210) → 210
Ceil(x): Returns the smallest integer that is greater than or equal to «x». See also Ceil().
Ceil(3.1) → 4
Ceil(5) → 5
Ceil(-2.9999) → -2
Ceil(-7) → -7
Ceil(x, digits): Returns the smallest number with the indicated of digits to the right of the decimal that is greater than or equal to «x». See also Ceil().
Ceil(Pi, 4) → 3.1416
Ceil(-12345, -2) → -12300
Ceil(x, ,dateUnit): Rounds a date-time «x» up to the indicated «dateUnit», where «dateUnit» can be 'Y', 'Q', 'M', 'D', 'h', 'm', or 's' (year, quarter, month, day, hour, minute, second).
Ceil(26-July-2017, dateUnit:'Y') → 1-Jan-2018
Ceil(26-July-2017, dateUnit:'M') → 1-Aug-2017
Ceil(26-July-2017, dateUnit:'D') → 26-July-2017
Floor(x): Returns the largest integer that is smaller than or equal to «x». See also Floor().
Floor(2.999) → 2
Floor(3) → 3
Floor(-2.01) → -3
Floor(-5) → -5
Floor(x, digits): Returns the largest number with the indicated number of digits past the decimal that is less than or equal to «x». See also Floor().
Floor(Pi, 4) → 3.1415
Floor(-12345, -2) → -12400
Floor(x, ,dateUnit): Rounds a date-time «x» down to the indicated «dateUnit», where «dateUnit» can be 'Y', 'Q', 'M', 'D', 'h', 'm', or 's' (year, quarter, month, day, hour, minute, second).
Floor(26-July-2017, dateUnit:'Y') → 1-Jan-2017
Floor(26-July-2017, dateUnit:'M') → 1-July-2017
Floor(26-July-2017, dateUnit:'D') → 26-July-2017
Round(x): Returns the value of «x» rounded to the nearest integer. See also Round().
Round(1.8) → 2
Round(-2.8) → -3
Round(1.499) → 1
Round(-2.499) → -2
Round(x, digits): Rounds the value of «x» to the number of decimal digits, indicated by «digits», to the right of the decimal point. See also Round().
Round(Pi, 1) → 3.100
Round(Pi, 3) → 3.142
Round(14243.4, -2) → 14200
Note: The Number Format setting determines how many digits are included when a number is displayed, while Round(x,digits)
returns a new rounded number so that the rounded value can be used in subsequent computations.
Exp(x): Returns the exponential of «x», e
raised to the power of «x». See also Exp().
Exp(5) → 148.4
Exp(-4) → 0.01832
Ln(x): Returns the natural logarithm of «x», which must be positive unless the system variable EnableComplexNumbers is set. See also Ln().
Ln(150) → 5.011
Ln(Exp(5)) → 5
Logten(x): Returns the logarithm to the base 10 of «x», which must be positive unless the system variable EnableComplexNumbers is set. See also Logten().
Logten(180) → 2.255
Logten(10^30) → 30
Sign(x): Returns -1 when «x» is negative, 1 when «x» is positive, 0 when «x» is zero, and NaN
when «x» is NaN
. See also Sign().
Sign(-15.2) → -1
Sign(7.3) → 1
Sign(0) → 0
Sign(0/0) → NaN
Sqr(x): Returns the square of «x». See also Sqr().
Sqr(5) → 25
Sqr(-4) → 16
Sqrt(x): Returns the square root of «x». «x» must be positive unless the system variable EnableComplexNumbers is set. See also Sqrt().
Sqrt(25) → 5
Sqrt(-1) → NAN
Sqrt(-1) → 1j { when EnableComplexNumbers is set }
Mod(x, y): Returns the remainder (modulus) of «x»/«y»
. See also Mod().
Mod(7, 3) → 1
Mod(12, 4) → 0
Mod(-14, 5) → -4
Factorial(x): Returns the factorial of «x», which must be between 0 and 170. See also Factorial().
Factorial(5) → 120
Factorial(0) → 1
If «x» is not an integer, it rounds «x» to the nearest integer before taking the factorial.
Logit(p): The inverse of the Sigmoid function, is defined for 0 < p < 1
and is equal to Ln(p / (1-p))
. See alse Logit().
Logit(0.5) →0
Logit(0.25) → -1.099
ProductLog(z): Returns the value for x that solves z = x * Exp(x)
. It is also known as the Lambert W function. It is real-valued for a real-valued parameter with z ≥ -Exp(-1)
. It is also defined for all complex numbers. For real-valued z with z<-Exp(-1)
, a complex result is returned only when EnableComplexNumbers is on, and in which case, the so called first branch or upper branch ([math]\displaystyle{ W_0(z) }[/math]) is returned. See also ProductLog().
ProductLog(0) → 0
ProductLog(100) → 3.386
3.386 * Exp(3.386) → 100
Sigmoid(x): The sigmoid function is also called the logistic function, the expit function, or the inverse logit function. It serves as a continuous approximation to the step function (x>=0)
. It approaches 0 as x approaches -Inf
, approaches 1 as x approaches Inf
and is 1/2 at x=0. It is equal to 1/(1+Exp(-x))
. See also Sigmoid().
Sigmoid(0) → 0.5
Sigmoid(1) → 0.7311
Cos(x), Sin(x), Tan(x): Return the cosine, sine, and tangent of «x», «x» assumed in degrees. See also Cos(x), Sin(x), Tan(x).
Cos(180) → -1
Cos(-210) → -0.866
Sin(30) → 0.5
Sin(-45) → -0.7071
Tan(45) → 1
Arctan(x): Returns the arctangent of «x» in degrees (the inverse of Tan). See also Arctan(x), Arccos(x), Arcsin(x), Arctan2(y, x) and Advanced math functions.
Arctan(0) → 0
Arctan(1) → 45
Arctan(Tan(45)) → 45
Degrees(r), Radians(d): Degrees(r) gives degrees from radians, and Radians(d) gives radians from degrees. See also Degrees(r) and Radians(d).
Degrees(Pi/2) → 90
Degrees(-Pi) → -180
Degrees(90) → -1.57079633
Degrees(180) → 3.141592654
See Also
- Numbers
- Number formats
- Text, Date, Math, and Financial Functions
- Advanced math functions
- Complex number functions
- EnableComplexNumbers
- Operators
- Sum
- Product
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