matrixvb 里的randM及stdM的意思

kkkkkk

下的卡尔曼滤波的程序
标红的两个函数是什么意思啊，谢谢解答

Public Sub krm1()
clf
ax = vbaxes(Picture1.hWnd)
t = 50
m = 3
n = 1
w = randM(m + 1)
v = randM(n)
c = zeros(m + 1)
qq1 = stdM(v).r1(1)
rvv = qq1 ^ 2
qq2 = stdM(w).r1(1)
rww = qq2 ^ 2
x = randM(t, m)
xx = horzcat(ones(t, 1), x)
yy = times(randn(t, 1), 2)
b = mldivide(xx, yy)
y = zeros(t, 1)
krmsub t, rww, rvv, c, b, xx, y, yy
I = colon(1, 1, t)
ax = plot(I, y, "r", I, yy, "b")
End Sub