
@b@cInput


@bDescription

This launches the data input/editing window. There are three input fields:
(1) the variable's name, (2) a description of the variable, and (3) actual
values. The first two are free form strings, and can be set to anything you
wish. The last accepts only float numbers (no string data, maybe in a future
version?).

As values are entered, they appear in the variable list. The Add, Delete,
Replace, and Insert buttons work interactively with the data lister and
input field. The clear button will erase all current values.

The easiest way to enter missing observations is to put some use the add
button to add blank lines to the lister. When the data is then read into
xldlas a requestor will appear asking you how to treat blank lines. Select
the missing observations option.


@bNotes

Values in the variable list can be fed into the input window by double
clicking on them.


@bSee Also

Data --> Edit, File --> Input



@b@cEdit


@bDescription

Edit uses the same routine as Input (see above) except that the user must
choose an existing variable.


@bNotes

Since the data being edited is actually dropped and then re-inputed, the
variable's position in subsequent listings will be altered.


@bSee Also

Data --> Input



@b@cDrop


@bDescription

The drop window allows you to erase current data in memory. There are two
main modes, selected via the All Obs or In Range buttons. When All Obs is
active, any variable selected for dropping is removed completely from
memory. In Range, by way of contrast, fills the existing variable with the
current value for a missing observation between From: and To:. If, however,
the resulting variable consists of nothing but missing observations, it is
dropped from memory as though All Obs had been active.

New variables in memory must be dropped or saved before you can exit xldlas.

@bNotes

Drop All is a very dangerous button.


@bSee Also

File --> Quit



@b@cRename


@bDescription

This calls up a simple input requestor which allows you to change the name
of an existing variable. If you want to change the description, you have to
edit the variable.


@bNotes

None


@bSee Also

Data --> Edit



@b@cDescribe

@bDescription

Describe generates a table showing the current variables in memory, the
number of observations in each variable, and any variable descriptions.
Output is logged to any existing log or texlog file.


@bNotes

None


@bSee Also

Data --> List



@b@cList

@bDescription

List generates a table showing the actual values contained in a variable.
Output is logged to any existing log or texlog file.


@bNotes

None


@bSee Also

Data --> Describe



@b@cLabel


@bDescription

Label allows you to attach a text label to the dataset as a whole. This
label will be displayed when any subsequent Describe command is performed.


@bNotes

None


@bSee Also

None



@b@cGenerate


@bDescription

Calls up a window which allows you to perform mathematical transformations
of existing data and store the resulting values in a new variable or
overwrite an existing variable. There are a lot of buttons in this window,
so things can get a little confusing. 

The basic idea is that you can perform mathematical operations on a
variable. The Name: and Desc: input fields are used to name and describe the
variable you are working on (!). If you want to overwrite an exisitng
variable, simply supply its name in the Name: input. Anytime you hit the
Write button, the current data (listed in the browser on the right) is
written to memory with the supplied variable name. 

The buttons in the lower left hand corner immediately affect the data you
are working on. If you push the log button, for example, your data will be
replaced with its base e log. The yellow missing and zero buttons will fill
the current observations with --- surprise suprise --- missing values and
zeros (respectively).

Use of the keypad buttons is a little more subtle. First, choose an operator
(+ by default), and then start clicking a number. Both your operator and
number clicks appear in windows. If you then select the Go button, the
specified operation will be performed. For example, when you first launch
the generate window, all values are set equal to 0. If you then click the
'-' button, followed by '100', and then Go, xldlas will subtract 100 from
each of your observations.

Generally, you'll want to perform transformations on existing data (rather
than a vector of 0's). That's where the choice button (labelled (current) by
default) comes into play. Suppose you have a variable called 'age_y' which is
measured in years, and you want to create a new variable called 'age_m' to
represent age in months. The first step is to select the variable 'age_y'
from the choice button (click and hold the left mouse button to move through
all existing variable names). Once selected the variable name will appear
(appended by [0]) in the relevant window. Click Go, and it will be read into
the data browser. Now click '*' '12', followed by Go, then supply the
variable name and select Write. Voila, new variable created.

Now, what does that little [0] mean after the variable's name? That is how
far the observations being read in should be offset. Suppose you have a
variable who's first three observations are {1, 2, 3}. If you read them in
with the index (the number between [ and ]) eqaul to 0, then you're data
browser will begin {1, 2, 3}. If, however, you click on the lag 1 button
just below the choice button, the [0] will change to a [-1]. Now if you
select Go, the first three observations will be {missing, 1, 2}. Conversly,
if you hit forw 1 (changing [0] to [1]), your first two observations will be
{2, 3}. This is very handy for offsetting time series data.

The generate functions take a little getting used to, and they are not very
useful for performing complex transformations. 

@bNotes

Unlike the original ldlas, xldlas does not require the program bc to perform
transformations on data.


@bSee Also

Data --> Edit
