MATLAB Built-in Functions
Several functions are built into MATLAB.
Contents
Numeric Functions
Most built-in functions operate on numeric arrays by applying the function element-wise. These include:
Mathematical functions
Name |
Meaning |
Notes |
abs(x) |
absolute value |
|
ceil(x) |
round toward positive infinity |
|
exp(x) |
exponentiation |
|
factorial(x) |
factorial |
|
fix(x) |
round toward 0 |
|
floor(x) |
round toward negative infinity |
|
log(x) |
natural logarithm |
|
log10(x) |
base-10 logarithm |
|
max(x) |
maximum |
optionally return index of maximum as well: [m,i]=max(x) |
min(x) |
minimum |
optionally return index of minimum as well: [m,i]=min(x) |
mod(x,d) |
modulo of x divided by d |
|
nthroot(x,n) |
nth root of x |
|
round(x) |
round to integer |
|
sqrt(x) |
square root |
|
Trig functions
Name |
Meaning |
sin |
sine |
cos |
cosine |
tan |
tangent |
cot |
cotangent |
sec |
secant |
csc |
cosecant |
asin |
inverse sine |
acos |
inverse cosine |
atan |
inverse tangent |
acot |
inverse cotangent |
asec |
inverse secant |
acsc |
inverse cosecant |
sinh |
hyperbolic sine |
cosh |
hyperbolic cosine |
tanh |
hyperbolic tangent |
coth |
hyperbolic cotangent |
sech |
hyperbolic secant |
csch |
hyperbolic cosecant |
asinh |
inverse hyperbolic sine |
acosh |
inverse hyperbolic cosine |
atanh |
inverse hyperbolic tangent |
acoth |
inverse hyperbolic cotangent |
asech |
inverse hyperbolic secant |
acsch |
inverse hyperbolic cosecant |
Type-checking functions
Name |
Meaning |
allfinite(x) |
are all elements finite |
anynan(x) |
are any elements NaN |
isfloat(x) |
is a floating-point array |
isinteger(x) |
is an integer array |
isnumeric(x) |
is a numeric array |
isreal(x) |
uses complex storage |
Array functions
Name |
Meaning |
linspace(a,b,n) |
row vector of n evenly-spaced elements starting at a and ending in b |
String Functions
These functions operate on a string array and return a string scalar:
Name |
Meaning |
join(s) |
join the elements of string matrix s |
join(s,d) |
join the elements of string matrix s using delimiter d |
Matrix Functions
These functions return a matrix:
Name |
Meaning |
diag(v) |
diagonal matrix from vector v |
eye(n) |
n x n identity matrix |
ones(n) |
n x n matrix of 1s |
ones(r,c) |
r x c matrix of 1s |
rand(n) |
n x n matrix of random numbers |
rand(r,c) |
r x c matrix of random numbers |
zeros(n) |
n x n matrix of 0s |
zeros(r,c) |
r x c matrix of 0s |
These functions operate on a matrix:
Name |
Meaning |
diag(m) |
diagonal vector from matrix m |
size(m) |
array of dimensions |
To demonstrate how the size function can be used:
>> A = [12 62 93 -8];
>> sz = size(A)
sz = 1×2
1 4
>> B = zeros(size(A))
B = 1x4
0 0 0 0