Managing Data in DADiSP

Datasets are DADiSP's proprietary data management system. Datasets provide users with a means of importing and exporting data to/from DADiSP. A Dataset contains one or more Series. Each channel, series, or signal imported into DADiSP is stored within a Dataset, and is referred to by its DATASET.VERSION.SERIES name.

 

The data import and export functions are available from the Data pull-down menu. DADiSP's Dataset import facility allows you to import DADiSP formatted files in a variety of formats, including ASCII, 8-bit Byte, 16-bit Integer, 32-bit Integer, 64-bit Integer, IEEE 32-bit Floating Point, or IEEE 64-bit Double Precision format. ASCII files can be comma (CSV), space, tab or newline delimited. The data files can be single or multi-channel files with or without file headers.

 

When you import data into a Dataset, you will want to have certain information such as the sampling rate, vertical and horizontal units, and the date/time acquired associated with each Series. This information is stored with the Dataset and Series, and can be viewed in the Information Box when the Series is loaded into a Window in the Worksheet by clicking on the "I" button in the toolbar. To set these parameters, DADiSP provides a default import header which you may edit during the import process, or you may create your own header, and load it during the import process.

 

A DADiSP header can either be included at the top of your data file or stored in a separate ASCII file on a disk. The header file consists of keywords and values. The DADiSP keywords are discussed below in detail; many keywords are optional.

 

If your data is regularly sampled (i.e., points are sampled at a fixed spacing or rate), then it is not necessary to import both the x-axis and the y-axis values. You only need to import the y-axis and specify the x-offset and either the sampling rate or the interval between samples. DADiSP handles evenly spaced samples very efficiently. If your data is not regularly sampled, then you must import both the x-axis and y-axis values and use the XY or XYINTERP or RESAMPLE functions. Refer to the DADiSP Function Reference Manual for more information on XY functions.

 

Data stored in DADiSP Datasets and Series can be exported to a file that is: ASCII, 8-bit Byte, 16-bit Integer, 32-bit Integer, 64-bit Integer, IEEE 32-bit Floating Point, or IEEE 64-bit Double Precision format. The Series can be exported with or without a DADiSP header. Exporting the data with a DADiSP header included in the file simplifies the import process.