如何将符号函数转换为矩阵函数
发布网友
发布时间：2022-04-25 00:57
共1个回答
热心网友
时间：2023-10-18 15:11
命令就是下面的，coeffs（）
>> syms x1 x2;
>> pdx1=pi*cos(pi*x1) + pi*cos(pi*x1)*cos(pi*x2)
pdx1 =
pi*cos(pi*x1) + pi*cos(pi*x1)*cos(pi*x2)
>> coeffs(pdx1)
ans =
[ 1, 1]
>> coeffs(pdx1,x1)
ans =
[pi*cos(pi*x1) + pi*cos(pi*x1)*cos(pi*x2)]
>> coeffs(pdx1,x2)
ans =
[pi*cos(pi*x1) + pi*cos(pi*x1)*cos(pi*x2)]
matlab解释
COEFFS Coefficients of a multivariate polynomial.
C = COEFFS(P) returns the coefficients of the polynomial P with
respect to all the indeterminates of P.
C = COEFFS(P,X) returns the coefficients of the polynomial P with
respect to X.
[C,T] = COEFFS(P,...) also returns an expression sequence of the
terms of P. There is a one-to-one correspondence between the
coefficients and the terms of P.
Examples:
syms x
t = 2 + (3 + 4*log(x))^2 - 5*log(x);
coeffs(expand(t)) = [ 11, 19, 16]
syms a b c x
y = a + b*sin(x) + c*sin(2*x)
coeffs(y,sin(x)) = [a + c*sin(2*x), b]
coeffs(expand(y),sin(x)) = [a, b + 2*c*cos(x)]
syms x y
z = 3*x^2*y^2 + 5*x*y^3
coeffs(z) = [5, 3]
coeffs(z,x) = [5*y^3, 3*y^2]
[c,t] = coeffs(z,y) returns c = [5*x, 3*x^2], t = [y^3, y^2]
