R help - Apr 2009 - How to create matrix for if-else application with "i"?

Dear R-friends,

Could you please help me with a problem?

I have a table with 4 columns: P,Z,S,T.

Sometimes z is smaller than s, sometimes z is greater than t. For these
smaller/greater z-values, I do need the associated p-value (see example below).

I need the whole range of "a" and "b", but I only get the
values of "25" for "a" and "5.5" for
"b".

Also "i" is always "[1]" for all values of p.

Could you please help on how to get a matrix form for all separate p-values (for
z<s and z>t)?

Thanks very much in advance!

Herbert



#################################
p<-fig8$P
z<-fi8a$Z
s<-fig8$S
t<-fig8$T

for(i in 1:length(p))
{
if (z[i]<s[i]) 
{
a<-print(p[i])
}
else
{
if (z[i]>t[i]) 
{
b<-print(p[i])
}
}
}
[1] 0.5
[1] 1
[1] 1.5
[1] 2
[1] 2.5
[1] 3
[1] 3.5
[1] 4
[1] 4.5
[1] 5
[1] 5.5
[1] 17
[1] 17.5
[1] 18
[1] 18.5
[1] 19
[1] 19.5
[1] 20
[1] 20.5
[1] 21
[1] 21.5
[1] 22
[1] 22.5
[1] 23
[1] 23.5
[1] 24
[1] 24.5
[1] 25
> a
[1] 25
> b
[1] 5.5

######################

--

Dear R-friends,

Could you please help me with a problem?

I have a table with 4 columns: P,Z,S,T.

Sometimes z is smaller than s, sometimes z is greater than t. For these
smaller/greater z-values, I do need the associated p-value (see example below).

I need the whole range of "a" and "b", but I only get the
values of "25" for "a" and "5.5" for
"b".

Also "i" is always "[1]" for all values of p.

Could you please help on how to get a matrix form for all separate p-values (for
z<s and z>t)?

Thanks very much in advance!

Herbert



#################################
p<-fig8$P
z<-fi8a$Z
s<-fig8$S
t<-fig8$T

for(i in 1:length(p))
{
if (z[i]<s[i])
{
a<-print(p[i])
}
else
{
if (z[i]>t[i])
{
b<-print(p[i])
}
}
}
[1] 0.5
[1] 1
[1] 1.5
[1] 2
[1] 2.5
[1] 3
[1] 3.5
[1] 4
[1] 4.5
[1] 5
[1] 5.5
[1] 17
[1] 17.5
[1] 18
[1] 18.5
[1] 19
[1] 19.5
[1] 20
[1] 20.5
[1] 21
[1] 21.5
[1] 22
[1] 22.5
[1] 23
[1] 23.5
[1] 24
[1] 24.5
[1] 25
> a
[1] 25
> b
[1] 5.5

######################
--

herbert8686 at gmx.de wrote:
> Dear R-friends,
>
> Could you please help me with a problem?
>
> I have a table with 4 columns: P,Z,S,T.
>
> Sometimes z is smaller than s, sometimes z is greater than t. For these
smaller/greater z-values, I do need the associated p-value (see example below).
>
> I need the whole range of "a" and "b", but I only get
the values of "25" for "a" and "5.5" for
"b".
>
> Also "i" is always "[1]" for all values of p.
>
> Could you please help on how to get a matrix form for all separate p-values
(for z<s and z>t)?
>
>   
Hi Herbert,
Try this:

smallz<-mytable$P[mytable$Z < mytable$S]
names(smallz)<-which(mytable$Z < mytable$S)
bigz<-mytable$P[mytable$Z > mytable$T]
names(bigz)<-which(mytable$Z > mytable$T)

The two vectors are unlikely to be the same length (unless there is 
something I missed) and so making a matrix out of them will probably 
fail, or at least cause trouble. You could get a list:

mynewlist<-list(smallz=smallz,bigz=bigz)

Jim

Is it really a table? (That is a specific class of object in R.)

You seem to be accessing it as a data.frame. Perhaps something along  
the lines of (untested):

subset(fig8, (Z < S | Z > T) )$P

-- 
David Winsemius


On Apr 10, 2009, at 5:54 AM, herbert8686 at gmx.de wrote:
> Dear R-friends,
>
> Could you please help me with a problem?
>
> I have a table with 4 columns: P,Z,S,T.
>
> Sometimes z is smaller than s, sometimes z is greater than t. For  
> these smaller/greater z-values, I do need the associated p-value  
> (see example below).
>
> I need the whole range of "a" and "b", but I only get
the values of
> "25" for "a" and "5.5" for "b".
>
> Also "i" is always "[1]" for all values of p.
>
> Could you please help on how to get a matrix form for all separate p- 
> values (for z<s and z>t)?
>
> Thanks very much in advance!
>
> Herbert
>
>
>
> #################################
> p<-fig8$P
> z<-fi8a$Z
> s<-fig8$S
> t<-fig8$T
>
David Winsemius, MD
Heritage Laboratories
West Hartford, CT