for(i in 1:length(p.values)){
  if(0 < p.values[i,1] <= 0.001) p<-c("***")
  else if(0.001 < p.values[i,1] <= 0.01) p<-c("**")
  else if(0.01 < p.values[i,1] <= 0.05) p<-c("*")
  else if(0.05<p.values[i,1]<=0.01) p<-c(".")
  else if(0.01<p.values[i,1]<= 1) P<-C(" ")
}
上述程序在R中始终运行不出来，运行提示如下：
for(i in 1:length(p.values)){
+   if(0 <= p.values[i,1] <= 0.001) p<-c("***")
Error: unexpected '<=' in:
"for(i in 1:length(p.values)){
  if(0 <= p.values[i,1] <="
>   else if(0.001 < p.values[i,1] <= 0.01) p<-c("**")
Error: unexpected 'else' in "  else"
>   else if(0.01 < p.values[i,1] <= 0.05) p<-c("*")
Error: unexpected 'else' in "  else"
>   else if(0.05<p.values[i,1]<=0.01) p<-c(".")
Error: unexpected 'else' in "  else"
>   else if(0.01<p.values[i,1]<= 1) P<-C(" ")
Error: unexpected 'else' in "  else"
> }
Error: unexpected '}' in "}"
> for(i in 1:length(p.values)){
+   if(0 < p.values[i,1] < 0.001) p<-c("***")
Error: unexpected '<' in:
"for(i in 1:length(p.values)){
  if(0 < p.values[i,1] <"
>   elseif(0.001 < p.values[i,1] < 0.01) p<-c("**")
Error: unexpected '<' in "  elseif(0.001 < p.values[i,1] <"
>   elseif(0.01 < p.values[i,1] < 0.05) p<-c("*")
Error: unexpected '<' in "  elseif(0.01 < p.values[i,1] <"
>   elseif(0.05<p.values[i,1]<0.01) p<-c(".")
Error: unexpected '<' in "  elseif(0.05<p.values[i,1]<"
>   elseif(0.01<p.values[i,1]< 1) P<-C(" ")
Error: unexpected '<' in "  elseif(0.01<p.values[i,1]<"
> }
Error: unexpected '}' in "}"