# [R] Help needed in R

From: AbouEl-Makarim Aboueissa <aaboueissa_at_usm.maine.edu>
Date: Sat, 01 Mar 2008 17:07:05 -0500

Dear ALL:

I have two quick questions about how to perform some steps in R. Could you please see the attached MS file if the data not clean enough in this email.

Thank you so much for all your helps.

Abou

Here it is:

Consider the following matrix:

data<-matrix(c(2,2,12,2,1,10,10,4,10,1,1,2,2,1,2,10,3,1,1,1,3,5,17,23,9,9,3,3,15,5,

```		  4,5,5,5,4,8,1,15,3,3,1,6,3,6,3,4,5,14,4,
0,0,0,0,0,1,1,0,1,1,0,1,1,0,0,1,0,1,0,0,0,1,0,0,0,0,0,0,1,1,0,1,1,1,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0),49,2)

[,1] [,2]
[1,]    2    0
[2,]    2    0
[3,]   12    0
[4,]    2    0
[5,]    1    0
[6,]   10    1
[7,]   10    1
[8,]    4    0
[9,]   10    1

[10,]    1    1
[11,]    1    0
[12,]    2    1
[13,]    2    1
[14,]    1    0
[15,]    2    0
[16,]   10    1
[17,]    3    0
[18,]    1    1
[19,]    1    0
[20,]    1    0
[21,]    3    0
[22,]    5    1
[23,]   17    0
[24,]   23    0
[25,]    9    0
[26,]    9    0
[27,]    3    0
[28,]    3    0
[29,]   15    1
[30,]    5    1
[31,]    4    0
[32,]    5    1
[33,]    5    1
[34,]    5    1
[35,]    4    0
[36,]    8    0
[37,]    1    0
[38,]   15    0
[39,]    3    0
[40,]    3    0
[41,]    1    0
[42,]    6    0
[43,]    3    0
[44,]    6    0
[45,]    3    0
[46,]    4    0
[47,]    5    0
```
[48,] 14 0
[49,] 4 0
```Q1. Column one is the data set, and column two is an indicator of 1 and 0. Some values
in column one corresponding to indicator 1 in column two are different, and some
are the same. There are 5 different groups of values in column one with indicator 1
in column two.

(a) How I can choose only one value (only one observation) from each of these groups to
develop a vector of length 5 as: (1   2    5   10  15).

(b) How I can find number of observations in each of these groups as a vector as:
(2     2    5    4   1).

```

These are the values with indicator 1.

[,1] [,2]

``` [1,]    1    1
[2,]    1    1
[3,]    2    1
[4,]    2    1
[5,]    5    1
[6,]    5    1
[7,]    5    1
[8,]    5    1
[9,]    5    1

[10,]   10    1
[11,]   10    1
[12,]   10    1
```
[13,] 10 1
[14,] 15 1

AbouEl-Makarim Aboueissa, Ph.D.
Assistant Professor of Statistics
Department of Mathematics & Statistics
University of Southern Maine
96 Falmouth Street
P.O. Box 9300
Portland, ME 04104-9300

Tel: (207) 228-8389
Fax: (207) 780-5607
Email: aaboueissa_at_usm.maine.edu

aboueiss_at_yahoo.com
Office: 301C Payson Smith

R-help_at_r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Sat 01 Mar 2008 - 22:16:20 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Mon 03 Mar 2008 - 16:30:18 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.