[Octave]
Octave $B$H(B MATLAB $B$K6&DL$7$F8@$($k9bB.2=$N $B$H=q$-D>$;$P3JCJ$KB.$/$J$j$^$9!#(B
$BAH$_9~$_4X?t$r;H$C$F(B for$BJ8$r$J$/$9(B
n = 1;
wns = randn(100000, 1);
for k=1:length(wns)
if wns(k)> a
idx(n) = k;
n = n+1;
end
end
$B$N%3!<%i$r!"(b
wns = randn(100000, 1);
idx = find(wns> a);
$BG[Ns$r6n;H$7$F(Bfor$BJ8$r$J$/$9Nc(B
for t=1:1000
sig(t) = sin(2*pi*100*t/sf);
end
$B$r!"(B
t = 1:1000;
sig = sin(2*pi*100*t/sf);
$B$H$7$^$9!#$b$A$C$H9bEY$JNc$O!"(B
f = 100:10:2000;
t = (1:1000)/sf;
for k=1:length(f)
sig(k,:) = sin(2*pi*f(k)*t);
end
$B$r!"(B
f = 100:10:2000;
ff = ones(length(f), 1).*f';
t = (1:1000)/sf;
sig = sin(2*pi*t*ff*t);
$B$G$9!#(B(M x 1) x (1 x N) = (M x N) $B9TNs7W;;$N8x<0$r;w$$=p$7$^$7$g$&(b:-)$b!#(b
$B$A$J$_$K!"$3$NNc$G$O!"Ls(B length(f)$BG\%a%b%j$rB?$/;HMQ$9$k$N$G!"%a%b%j$,(B
$B>/$J$$>l9g$O(B HDD$B$X$N%9%o%C%W%,%j%,%j$G%A%g!
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for k=1:10000 if x(k)> 2 y(k) = x(k)^2+5; elseif x(k) < -2 y(k) = x(k)^3-5; else y(k) = x(k); end end$B$r!"(B
y = (x> 2).*(x.^2+5) + (x < -2).*(x.^3-5) + (x <= 2 & x>= -2).*x;$B$J$s$F=q$1$A$c$&$N$G!"%b%&BgJQ(B!!$B!#(B akira@rsch.tuis.ac.jp