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Opening SPLUS Data Files Using the File Menu
Opening SPLUS Data Files Using the openData Function
Importing Formatted Data Files Using the Import Menu
Importing Formatted Data files Using the import.data Function
Importing Free Formatted Data Files Using the read.table Function
Importing Data Files Using the scan Function
Importing Fixed Format Files Using the read.table Function
Exporting Data Files Using the write.table Function
Opening SPLUS Data Files Using the File Menu
You have can opan an SPLUS data file (.sdd extension) by using the
file menu. This method will open the data file in a data editor.
File Open Data then browse to the directory which contains the data file
Opening SPLUS Data Files Using the openData Function
You can also open an SPLUS data file by the openData function but note that this method does
not open the data file in a data editor. To see the data in a data editor you have to then use
the Data menu, select Data and then select the data file that you want to see in the data editor.
data.new <- openData('d:/file_name.sdd')
Importing Formatted Data Files Using the Import Menu
There many ways of inputting data and one of the easiest methods is to use the
import data menu in the file menu.
File Import Data From File...
If you are trying to import a formatted data file you first change the file
type to all files to see all the files available then you use the browse
bottom and browse to where your data is located then double click on the file that you want to import. The SPLUS import function
should automatically select the correct file type in the File Format field. If
it does not select the correct file type you will have to select it yourself by clicking on the arrow that brings up the
file type selection and then highlighting the correct file type.
SPLUS 2000 will import ASCII files with various types of delimiters including space, comma and user specified
delimiters; SPSS (.sav and .por) and SAS files (.sd2, .ssd01,
.ssd04, and .tpt). Unfortunately, in SPLUS 2000 there are a number of formats that do not seem to be supported through the
import menu. The STATA data files do not seem to be able to be imported through
the import menu, however, they can be imported by using
the import function via syntax which is discussed in the "importing using the
import function" section.
For the complete list of data files that can be imported into SPLUS 2000 wia the
import menu please refer to the manual.
SPLUS v6.1 will also import all the same types of ASCII files with various delimiters including space, comma and user specified delimiters; it will also import STATA data files (.dta), SPSS (.sav and .por), SAS files (.sas7bdat, .sd2, .ssd01, .ssd04, .sd7, .xpt, and .tpt) and dBase files. Note that it will not import STATA version 7 SE files since the SE version of STATA was developed later than the SPLUS version 6.1. For the complete list of data files that can be imported into SPLUS v6.1 using the import menu please refer to the manual.
Importing Formatted Data Files Using the import.data Function
The import function can import any formatted data file of the following form: "ACCESS", "ASCII", "DBASE", "EXCEL", "FASCII", "GAUSS", "LOTUS", "MATLAB", "ODBC", "PARADOX", "QUATTRO", "SAS", "SAS_TPT", "SPLUS", "SIGMAPLOT", "SPSS", "SPSS_POR", "STATA", "SYSTAT". The import function will allow you to import any STATA data file (version 4, 5, 6 and 7). Beware that SPLUS 2000 may not support the most current versions of the other types of formatted files. For example, it will only import SAS version 6 files (.sd2 extensions) as well as SAS export files (.tpt extensions). Note the use of the double backslashes in the file address. Here are examples of importing a SAS data file called test.sd2, an ASCII file which is space delimited called test.txt and a STATA 7 SE data file called test.dta. If you have saved these files on the D drive of your computer then the syntax would look like the following programs. Note that SPLUS is case sensitive. Furthermore, note that the names of the SPLUS data frames are totally arbitrary. The data frame test.sas could just as well have been named "potato" or "aunt.moe".
import.data(DataFrame="test.sas", FileName="d:/test.sd2", FileType = "SAS")
print(test.sas)
MAKE MODEL MPG WEIGHT PRICE
1 AMC Concord 22 2930 4099
2 AMC Pacer 17 3350 4749
3 AMC Spirit 22 2640 3799
4 Buick Century 20 3250 4816
5 Buick Electra 15 4080 7827
import.data(DataFrame="test.txt1", FileName="d:/test.txt", FileType="ASCII")
print(test.txt1)
make mpg weight price
Concord AMC 22 2930 4099
Pacer AMC 17 3350 4749
Spirit AMC 22 2640 3799
Century Buick 20 3250 4816
Electra Buick 15 4080 7827
import.data(DataFrame="test.stata", FileName="d:/test.dta", FileType = "STATA")
print(test.stata)
make model mpg weight price
1 AMC Concord 22 2930 4099
2 AMC Pacer 17 3350 4749
3 AMC Spirit 22 2640 3799
4 Buick Century 20 3250 4816
5 Buick Electra 15 4080 7827
Importing Free Formatted (Delimited) Data Files Using the read.table Function
The read.table function is very useful when reading in ASCII files that contain rectangular data. When the file contains the variable names in the first line of data the option header should be set to True. This function can read ASCII files with any type of delimiter as well as fixed format files. The default delimiter is blank space, other delimiters must be specified by using the sep option and setting it equal to the delimiter in quotes (i.e., sep=";" for the semicolon delimited data file).
Here are some examples of data with different types of delimiters. The data called testsemicolon.txt has semicolon delimiters and the dataset test called testz.txt uses the letter z as a delimiter both of which are acceptable delimiters in SPLUS. The option row.names=NULL forces the row names to be the observation number.
test.semi <- read.table("d:/testsemicolon.txt", header=T, sep=";", row.names=NULL)
print(test.semi)
make model mpg weight price
1 AMC Concord 22 2930 4099
2 AMC Pacer 17 3350 4749
3 AMC Spirit 22 2640 3799
4 Buick Century 20 3250 4816
5 Buick Electra 15 4080 7827
test.z <- read.table("d:/testz.txt", header=T, sep="z", row.names=NULL)
print(test.z)
make model mpg weight price
1 AMC Concord 22 2930 4099
2 AMC Pacer 17 3350 4749
3 AMC Spirit 22 2640 3799
4 Buick Century 20 3250 4816
5 Buick Electra 15 4080 7827
Importing Data Files Using the scan Function
The scan function is an extremely flexible tool for importing data. It can be used
to read in almost any type of data, numeric, character or complex and it can be
used for fixed or free formatted files. Moreover, by using the scan function it is
possible to input data directly from the console. The scan function reads the fields of
data in the file as specified by the what option with the default being numeric. If
the what option is specified to be what=character() or what=" " then all the
fields will be read as strings. If the data is a mix of numeric, string or complex data then
a list can be used in the what option. The default separator for the scan function
is any white space (single space, tab, or new line). However, unlike the read.table
function which returns a data frame, the scan function returns a list or
a vector. This makes the scan function less useful for inputting
"rectangular" data such as the car data set that was seen in the
previous examples.
In the following examples we input first numeric data and then string data directly from the console; then
we input the text file, scan.txt, where the first variable is a string variable and the
second variable is numeric.
#inputting data directly from the console in the Commands window
x <- scan()
3 5 6 9
2 5 6
x
1: 5: 8: [1] 3 5 6 9 2 5 6
#inputting string data directly from the console in the Commands window
name.x <- scan(, what="")
bobby
kate dave
mia
name.x
1: 2: 4: 5: [1] "bobby" "kate" "dave" "mia"
#inputting a text file and outputting a list
x <- scan("d:/scan.txt", what=list(age=0, name=""))
x
$age
[1] 12 24 35 20
$name
[1] "bobby" "kate" "david" "michael"
#using the same text file and saving only the names as a vector
x <- scan("d:/scan.txt", what=list(NULL, name=character()))
x <- x[sapply(x, length) > 0]
x
$name
[1] "bobby" "kate" "david" "michael"
is.vector(x)
[1] TRUE
Importing Fixed Format Files Using the read.table Function
For fixed format files the variables names are often in a separate file from the data. In this example the variable names are in a file called names and the data are in a file called testfixed.txt. This is especially convenient when the fixed format file is very large and has many variables then it becomes rather impractical to have to type in all the variable names. In this situation the sep option is used to specify the column number where each variable begins and the col.name option specifies the file containing the variable names. So, first we read in the file for the names using the scan function. The what option is where we specify that the values in the file are character values. The print function with argument "names" shows us that the names is a list of string values. By using the col.names option in the read.table function this list will supply the variables names.
names <- scan("d:/names.txt", what=character() )
print(names)
[1] "model" "make" "mph" "weight" "price"
test.fixed <- read.table("d:/testfixed.txt", col.names=names, row.names=NULL, sep = c(1, 6, 13, 15, 19))
print(test.fixed)
model make mph weight price
1 AMC Concord 22 2930 4099
2 AMC Pacer 17 3350 4749
3 AMC Spirit 22 2640 3799
4 Buick Century 20 3250 4816
5 Buick Electra 15 4080 7827
Exporting Files Using the write.table Function
The write.table function outputs data files. The first argument specifies which data frame is to be exported. The next argument specifies the file to be created. The default separator is a blank space but any separator can be specified in the sep option. The default value for both the row.names and col.names options is TRUE. In the example we specify that we do not wish to include row names. The default setting for the quote option is to include quotes around all the character values, i.e. around values in string variables and around the column names. As we have shown in the example it is very common not to want the quotes when creating a text file.
#using the test.csv data frame to write a text file with no row names #and without quotes around the character values (both column names and string variables) write.table(test.csv, "d:/test1.txt", row.names=F, quote=F)
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