Pick Columns To Plot

Allows you to specify which columns within a multiple-column file to plot. Up to 20 rows from the selected file are displayed in the read-only box on the left side of the dialog box. Each column is preceded by a heading with the column number as interpreted by DPlot. If the column numbers do not match up with what you expected, or if the displayed text does not start with the first data line, then DPlot had difficulty in determining either the number of columns or the start of the data, or both. For more information see the description of file type D in the Open Command Help topic.

By default, DPlot uses the first column of data in multi-column files for the X axis values. If there is only one column of data, DPlot starts X at 0 and increments by 1 for each additional row. Subsequent columns (or the first column in single-column files) are used for the Y values, each sharing the same X.

To change the column number used for the X axis values, enter a number in the Use column __ for X Axis box. This entry cannot be a text column. If this number is 0, then DPlot starts X at 0 and increments X by 1 for each additional row of data values.

Select columns to use for the Y values by checking the appropriate check boxes under Use these columns for Y. Note that you cannot select a column to serve as both the X Axis values and the Y values for a curve, nor can you select text columns (anything other than numbers, currencies, dates, times, or date-time pairs).

Alternatively, if the file contains alternating X,Y columns, as in:

X(1,1) Y(1,1) X(1,2) Y(1,2)

X(2,1) Y(2,1) X(2,2) Y(2,2)

X(3,1) Y(3,1) X(3,2) Y(3,2)

etc., then you should check the box labelled Alternating X,Y columns. In this case DPlot will disable the even-numbered (Y) columns. Checking an X column will automatically cause the corresponding Y column to be checked. Alternating X,Y columns cannot be selected if the total number of columns in the file is an odd number, or if the file contains any non-numeric columns.

Labels

For X,Y data files containing 3 (and only 3) columns or for 3D data files containing 4 columns, you may specify that the last column contains point labels. For example this data:

0.0, 0.000000000,"X=$X, Y=$Y"

0.1, 0.309016994,

0.2, 0.587785252,

0.3, 0.809016994,

0.4, 0.951056516,

0.5, 1.000000000,"X=$X, Y=$Y"

0.6, 0.951056516,

0.7, 0.809016994,

0.8, 0.587785252,

0.9, 0.309016994,

1.0, 0.000000000,"X=$X, Y=$Y"

1.1,-0.309016994,

1.2,-0.587785252,

1.3,-0.809016994,

1.4,-0.951056516,

1.5,-1.000000000,"X=$X, Y=$Y"

1.6,-0.951056516,

1.7,-0.809016994,

1.8,-0.587785252,

1.9,-0.309016994,

2.0, 0.000000000,"X=$X, Y=$Y"

will produce this plot:

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