Return to Answer

Octave / Matlab, 74 67 bytes

Rejection method, 67 bytes:

u=1;v=1;while hypot(u,v)>1
u=rand;v=rand;end
sprintf('(%f,%f)',u,v)

Direct method, 74 bytes (thanks Martin Büttner for helping me correct errors):

t=rand*2*pi;r=1-abs(1-sum(rand(2,1)));sprintf('(%f,%f)',r*cos(t),r*sin(t))

Octave / Matlab, 74 64 bytes

Rejection method, 64 bytes:

u=1;v=1;while u^2+v^2>1
u=rand;v=rand;end
sprintf('(%f,%f)',u,v)

Direct method, 74 bytes (thanks to Martin Büttner for helping me correct two errors):

t=rand*2*pi;r=1-abs(1-sum(rand(2,1)));sprintf('(%f,%f)',r*cos(t),r*sin(t))

Octave / Matlab, 56 bytes

t=rand*2*pi;u=rand;sprintf('(%f,%f)',u*cos(t),u*sin(t))

Octave / Matlab, 74 67 bytes

Rejection method, 67 bytes:

u=1;v=1;while hypot(u,v)>1
u=rand;v=rand;end
sprintf('(%f,%f)',u,v)

Direct method, 74 bytes (thanks Martin Büttner for helping me correct errors):

t=rand*2*pi;r=1-abs(1-sum(rand(2,1)));sprintf('(%f,%f)',r*cos(t),r*sin(t))

Octave / Matlab

t=rand*2*pi;sprintf('(%f,%f)',cos(t),sin(t))

Octave / Matlab, 56 bytes

t=rand*2*pi;u=rand;sprintf('(%f,%f)',u*cos(t),u*sin(t))