[R] Error in lm.fit(

[Peter Lauren]

I am using R.2.4.1 on Windows XP 5.1 (SP 2).

I have the following line in my R code.

Analysis=anova(lm(PM ~ x))

It works the first 60 or so times it is called but
then I get the following error message.

Error in lm.fit(x, y, offset = offset, singular.ok =
singular.ok, ...) : 0 (non-NA) cases

In order to examine the input, I preceeded the call
with the following.

print(PM)
print(x)

This gave the following.

[1] 245.0 189.0 249.8 188.0 184.3 230.0 147.0 185.3
196.0 142.3 282.0 169.0
[13] 231.5 162.0 115.0 168.8 195.0 214.0 173.0 111.3
360.0 192.3 305.5 206.0
[25] 111.0 247.0 188.0 246.0 252.0 114.0

 [1] 20.00 20.00 20.00 20.00 20.00 10.00 10.00 10.00
10.00 10.00  7.50  7.50
[13]  7.50  7.50  7.50  5.00  5.00  5.00  5.00  5.00 
2.50  2.50  2.50  2.50
[25]  2.50  1.25  1.25  1.25  1.25  1.25

I would be most grateful if someone could help with
this problem.  I do not see why these input vectors
would give this error message.  

Also, is there a way to make it so the script keeps
running if it gets an error like this?

Many thanks in advance,
Peter Lauren.