What does conv () mean in matlab?

conv (vector convolution operation)

The convolution of two vectors is actually a polynomial multiplication. ?

for example, p = [123] and q = [11] are two vectors, and the convolution calculation method of p and q is as follows:?

Take the element of p as the coefficient of a polynomial, and the polynomials are arranged in ascending power (or descending power), for example, write the corresponding polynomial according to ascending power: 1+2x+3x 2;

similarly, arrange the elements of q as coefficients of polynomial in ascending order, and write the corresponding polynomial: 1+x ..

Convolution means "multiplying two polynomials to get a coefficient". ?

（1+2x+3x^2）×（1+x）=1+3x+5x^2+3x^3?

so the result of convolution of p and q is [1 3 5 3]

note: when it is determined that the previous sequence is arranged in ascending or descending power, the latter sequence should also be arranged in this way, otherwise the result is wrong.

p = [1 2 3]; q=[1 1]; ?

conv(p,q)

ans =

1 ? 3 ? 5 ? 3

Extended data:

convn function in p>matlab

Syntax format:

w=convn(u,v);

calculate the convolution of matrices u and v, and the size of w is size (u)+size (v)-1;

w=convn（u,v,'shape'）;

returns a part of the convolution, which is determined by the parameter shape:

full? Returns the complete convolution (default);

same? Returns the central part of the convolution, which has the same size as u;

valid only returns those parts of the convolution that are calculated but not filled with zeros, and the size of w is max (size (u)-size (v)+1,).

Baidu encyclopedia-convolution