Statistical functions
Beta and noncentral beta distributions
Cumulative beta distribution
Probability density of the beta distribution
Right-tailed beta distribution
Inverse cumulative beta distribution
Inverse of the upper-tailed distribution
Cumulative noncentral beta distribution
Probability density of the noncentral beta distribution
Inverse cumulative noncentral beta distribution
Binomial distribution
Cumulative binomial distribution
Probability mass of the binomial distribution
Right-tailed binomial distribution
Inverse cumulative binomial distribution
Inverse of the upper-tailed binomial distribution
Cauchy distribution New
Cumulative Cauchy distribution
Probability density of the Cauchy distribution
Reverse cumulative Cauchy distribution
Inverse cumulative Cauchy distribution
Inverse upper-tailed Cauchy distribution
Natural log of the Cauchy density
Chi-squared distribution
Cumulative chi-squared distribution
Probability density of chi-squared distribution
Right-tailed chi-squared distribution
Inverse cumulative chi-squared distribution
Inverse of the upper-tailed chi-squared distribution
Noncentral chi-squared distribution
Cumulative noncentral chi-squared distribution
Inverse cumulative noncentral chi-squared distribution
Noncentrality parameter of the noncentral chi-squared distribution
Probability density of noncentral chi-squared distribution
Reverse cumulative noncentral chi-squared distribution
Inverse of upper-tailed noncentral chi-squared distribution
Dunnett’s multiple range
Cumulative Dunnett’s multiple range distribution
Inverse cumulative Dunnett’s multiple range distribution
Exponential distribution*
Probability density of the exponential distribution
Cumulative exponential distribution
Reverse cumulative exponential distribution
Inverse cumulative exponential distribution
Inverse upper-tailed exponential distribution
F and noncentral F distributions
Cumulative F distribution
Probability density of the F distribution
Right-tailed F distribution
Inverse cumulative noncentral F distribution New
Inverse cumulative F distribution
Inverse of the upper-tailed distribution
Cumulative noncentral F distribution
Probability density of the noncentral F
Right-tailed noncentral F distribution
Inverse upper-tailed noncentral F distribution
Noncentrality parameter of the noncentral F distribution
Gamma distribution
Cumulative gamma distribution
Probability density of the gamma distribution
Right-tailed gamma distribution
Inverse cumulative gamma distribution
Inverse of the upper-tailed distribution
Partial derivatives of the cumulative gamma distribution
Second partial derivatives of the cumulative gamma distribution
Natural log of the inverse gamma density*
Hypergeometric distribution
Cumulative hypergeometric distribution
Probability mass of the hypergeometric distribution
Inverse Gaussian distribution
Cumulative inverse Gaussian distribution
Probability density of the inverse Gaussian distribution
Reverse cumulative inverse Gaussian distribution
Inverse cumulative inverse Gaussian distribution
Inverse upper-tailed inverse Gaussian distribution
Natural log of the inverse Gaussian density
Laplace distribution New
Cumulative Laplace distribution
Probability density of the Laplace distribution
Reverse cumulative Laplace distribution
Inverse cumulative Laplace distribution
Inverse upper-tailed Laplace distribution
Natural log of the Laplace density
Logistic distribution*
Probability density of the logistic distribution
Cumulative logistic distribution
Reverse cumulative logistic distribution
Inverse cumulative logistic distribution
Inverse upper-tailed logistic distribution
Negative binomial distribution
Cumulative negative binomial distribution
Probability mass function of the negative binomial distribution
Right-tailed negative binomial distribution
Inverse cumulative negative binomial distribution
Inverse of the upper-tailed negative binomial distribution
Normal, log of the normal, and binormal distributions
Cumulative bivariate normal distribution
Cumulative standard normal distribution
Probability density of the normal distribution
Inverse cumulative standard normal distribution
Log of the cumulative standard normal distribution
Log of the probability density of the normal distribution
Natural log of the multivariate normal density*
Poisson distribution
Cumulative Poisson distribution
Probability mass of the Poisson distribution
Right-tailed Poisson distribution
Inverse cumulative Poisson distribution
Inverse of the upper-tailed Poisson distribution
Student’s t and noncentral Student’s t distributions
Cumulative Student’s t distribution
Robability density of the Student’s t distribution
Right-tailed Student’s t distribution
Inverse cumulative Student’s t distribution
Inverse of the upper-tailed Student’s t distribution*
Cumulative noncentral Student’s t distribution
Probability density of the noncentral Student’s t distribution
Right-tailed noncentral Student’s t distribution
Inverse cumulative noncentral Student’s t distribution New
Inverse of the upper-tailed noncentral Student’s t distribution
Noncentrality parameter of the noncentral Student’s t distribution
Tukey’s Studentized range
Cumulative Tukey’s Studentized range distribution
Inverse cumulative Tukey’s Studentized range distribution
Weibull distribution*
Probability density of the Weibull distribution
Cumulative Weibull distribution
Upper-tailed Weibull distribution
Inverse cumulative Weibull distribution
Inverse upper-tailed Weibull distribution
Weibull (proportional hazards) distribution
Probability density of the Weibull (proportional hazards) distribution
Cumulative Weibull (proportional hazards) distribution
Reverse cumulative Weibull (proportional hazards) distribution
Inverse cumulative Weibull (proportional hazards) distribution
Inverse upper-tailed Weibull (proportional hazards) distribution
Wishart and inverse Wishart distributions*
Natural log of the density of the Wishart distribution
Natural log of the density of the inverse Wishart distribution
Date and time functions
Complete suite of functions for manipulating dates and datetimes, including support for business calendars and leap seconds
Convert dates and datetimes in string form to numeric form with great flexibility, including support for any order of year, month, day, hour, minute, second, and millisecond
Extract day, day of week, week of year, month, quarter, half-year, or year from specified date
Extract hour, minute, second, or millisecond from specified time or datetime, including optional adjustments for leap seconds
Convert between units of date and time
Convert between business dates and regular dates
Matrix functions
Stata has a powerful matrix language called Mata that contains hundreds of functions.
Below, we list some basic matrix functions that are provided within Stata. All of the same functionality, and more, is provided in Mata too. Mata is included with Stata.
Determinant of matrix
Trace of matrix
Number of rows of matrix
Number of columns of matrix
Number of zeros on diagonal of matrix
Floor of matrix element
Check if matrix is symmetric
Check for missing elements in matrix
Relative difference of two matrices
Column number associated with specified column name
Row number associated with specified row name
Identity matrix
Inverse of matrix
Cholesky decomposition
Hadamard matrix
Sweep matrix
Correlation matrix of variance matrix
Diagonal matrix from vector
r x c matrix with each element equal to z
r x c matrix with elements containing uniformly distributed pseudorandom numbers in [0,1]
Column vector from matrix
Random-number functions
Uniform over interval (0,1)
Uniform over interval (a,b)*
Uniform integers over interval [a,b]*
Standard normal
Normal, mean m and std. deviation 1
Normal, mean m and std. deviation s
Beta
Binomial
Cauchy New
Chi-squared
Exponential*
Gamma
Hypergeometric
Inverse Gaussian
Laplace New
Logistic, mean 0 and std. deviation π/√3*
Logistic, mean 0, scale s, std. deviation sπ/√3*
Logistic, mean m, scale s, std. deviation sπ/√3*
Negative binomial
Poisson
Student’s t
Weibull, shape a, scale b*
Weibull, shape a, scale b, location g*
Weibull (proportional hazards), shape a, scale b*
Weibull (proportional hazards), shape a, scale b, location g*
Random-number generators
64-bit Mersenne Twister generator*
Stream version of 64-bit Mersenne Twister
Allow random numbers to be drawn correctly on multiple machines or in multiple processes
Each stream is independent of other streams
When the stream generator is used, all random-number functions automatically become stream enabled.
32-bit KISS generator
Mathematical functions
Programming functions
Absolute value
Ceiling
Combinatorial
Floor
Maximum
Minimum
Modulus
Relative difference
Round of x in units of y
Running sum
Sign
Truncation
Common transcendental functions
Natural logarithm
Base-10 logarithm
Exponential
Natural log of n factorial
Complementary log-log
Inverse of the complementary log-log
Logit
Inverse of the logit
Square root
Natural log of gamma
digamma
trigamma
Trigonometric functions
Sine of radians
Cosine of radians
Tangent of radians
Arcsine returning radians
Arccosine returning radians
Arctangent returning radians
Two-argument arctangent
Inverse hyperbolic sine
Inverse hyperbolic cosine
Inverse hyperbolic tangent
Hyperbolic sine
Hyperbolic cosine
Hyperbolic tangent
Time-series functions
Return whether time is within a specified range, excluding the range’s endpoints
Return whether time is within a specified range, including the range’s endpoints
String functions
Full Unicode (UTF-8) support*
Abbreviation
Concatenation
Duplication
Reduce multiple, consecutive internal blanks to one blank
Remove leading blanks
Remove trailing blanks
Remove both leading and trailing blanks
Lowercase string
Convert string to “proper” case
Uppercase string
Locale-aware “titlecase” string*
Pluralize string
Reversed string
Substitution of characters for pattern found in string
Substitution of characters for word found in string
Extract substring
Length of string
Position of first character in string in list of match characters
Position of first character in string not in list of match characters
Position of string in another string
nth word of string
Number of words in string
Convert string to numeric
Convert numeric to string
Sort and compare Unicode strings based on locale*
Regular expression pattern matching
Regular expression pattern replacement
Regular expression pattern subexpressions
Convert string to valid Stata name
Wildcard pattern matching
Convert strings to/from Unicode (UTF-8) and extended ASCII*
Escape and unescape Unicode (UTF-8) strings*
Unicode character for code point*
Code point for Unicode character*
ASCII character for decimal number
Soundex code for string
U.S. Census soundex code for string
Watch Unicode in Stata.
Low-level programming functions
Partition interval into n equal-length intervals
Recode number into one of several specified categories
Byte order of computer architecture on which Stata is currently running
Version of caller of currently running program to assist with backward compatibility version control
Round if rounding does not exceed specified tolerance
Convert number to single-precision floating-point value
Restrict returned value to a range
Conditional function to return one value if argument is true and another value if argument is false
Check for any missing value in set or arguments
Access to system parameters, system constants, and current setting values
Access to results of Stata commands
Return whether observation is in estimation subsample
Check whether value is in a list of arguments, string or numeric
Check whether value lies within a specified range of numbers or strings
Return maximum output width for value displayed with specified display format
Access to machine precision of double- and single-precision floating-point numbers
Access to cutoff value for normalized/denormalized IEEE double-precision floating point numbers
Access to largest and smallest possible values of each numeric Stata variable storage type
Read contents of file into string
Write string to file
Check whether file exists
Normalize Unicode strings*
Search for invalid UTF-8 sequences*