skip to main content NIST Center for Neutron Research NIST Center for Neutron Research National Institute of Standards and Technology
Home Instruments Science Experiments SiteMap
DAVE, Data Analysis and Visualization Environment
DAVE Home Features Changelogs Screenshots Downloads Citations DAVE/IDL documentation

New features in DAVE 2.x

Key Elements in DAVE 2.x series

The DAVE 1.x series essentially consisted of several major, relatively independent, application modules that shared a common launch pad and application preferences. Only one dataset could be loaded at any one time in the main application and this dataset could be shared with any application module at its launch. This posed a serious limitation on the addition of modules that could operate on two or more persistent datasets.

In the DAVE 2.x series, a major effort has been made to design an application which is much more integrated and takes advantage of the iTools application framework in IDL. The iTools framework makes extensive use of object oriented programming (OOP) and consists of a set of classes and associated utilities that are designed to facilitate the development of sophisticated applications containing standard features including:

Using the iTools as a foundation, we have been come with a radically different radically different design approach consisting of the following key elements.

Project Space

A user session with the DAVE application always occurs within the concept of a project. A project can be saved and the application closed. A project can be resumed when the application is restarted. The save action should preserve all data and other useful application state information so that the user is able to return to the project at some later time. This functionality gives users the option of analyzing and or visualizing related datasets together and then saving the results in a project. Multiple projects can, of course, be created based on criteria such as experiment or instrument type.

Data Reduction

In DAVE2, as in DAVE1, special modules are provided for performing data reduction, that is converting raw data into the scattering function. Data reduction covers a broad set of tasks which are typically instrument specific and consequently, the data reduction modules will be unique and designed to meet the needs of particular instruments.

Data Input/Output

Support for the following data file formats are provided in DAVE.

Data Manager

The Data Manager is responsible for providing the interface through which the user can interact with all data that is currently loaded in the application. The interface is a tree widget that provides a hierarchical view that is used to organize data structures and information. The nodes and branches of the tree view can be expanded or collapsed depending on the level of detail that is required for the components of the dataset under examination.

Visualization Manager

The Visualization Manager provides the base functionality required for user interaction with the visualizations that have been created in the system. Visualizations are visual representations of data such as line plots, images and surface displays. Because multiple visualizations can be created, it is necessary to provide a means for the user to manage them effectively and intuitively. The interface for this is also a tree widget that enables a hierarchical arrangement of complex information without compromising on the amount of detail that can be included.

Data Visualization

Visualizations provide a graphic representation of the data and there is a limited number of ways in which this can be done. DAVE2 provides comprehensive support for all types of visualizations - thanks to the extensive features already present in the iTools framework. The list of supported visualizations include the following.

Supersets of these individual visualizations such as image-contour, surface-image and surface-contour are also possible.

Data Analysis

Most data analysis features are encapsulated into iTools components known as operations. Operations are well defined components that can be used to modify data, visualizations or application state. The number of data analysis tasks is extensive and what follows is an incomplete list of currently available or planned features.

Miscellaneous Tools

These are independent, self-contained tools that are useful for performing tasks in DAVE that cannot be categorised as data reduction, analysis or visualization. These are located in the Planning Tools and Misc Tools top level menus.

New features in DAVE 1.5

As with previous stable releases, there have been numerous upgrades to DAVE in version 1.4 as well as the introduction of new application modules. Some of the more notable changes includes the following modules (click on the hyperlinks to view a brief description): TAS Data Reduction,Mslice ,MagProp,PAN,HFBS

TAS Data Reduction

Menu location: Data Reduction => NCNR => TAS => BT7 PSD Reduction

New module used for reducing data taken on BT7 with the new position-sensitive detector and analyzer package.

Menu location: Data Reduction => NCNR => TAS => SPINS PSD Calibration

New module that determines the efficiencies and energy calibration for the position-sensitive detector on the SPINS instrument.

Menu location: Tools => General Tools => Miscellaneous Tools => BT1 to DAVE Converter

New module used to convert BT1 Files into the DAVE format for quick view using DAVE visualization tools.


Menu location: Data Reduction => NCNR => DCS => DCS Mslice

Upgrade Mslice with additional data reduction features for DCS.

Mslice now includes support for inverse geometry instruments.


Menu location: Data Analysis => MagProp (Workup and Analysis of Magnetic Data)

New program module for the workup, visualisation and analysis of magnetic data, incorporating a Hamiltonian matrix generator that allows the user to generate a matrix representation of a given Hamiltonian from a symbolic expression. In future, it will be extended to calculate EPR and INS spectra that can be compared directly with experiment.


Menu location: Data Analysis => PAN(Peak Analysis)

Upgrade: new feature in PAN allowing groups in a single DAVE file to have different independent variable ranges.  Also allows users to mask individual data points.

HFBS Raw Data Detector View

Menu location: Tools => NCNR Tools => HFBS Tools => Raw Data Detector View

New. Given a raw HFBS data file, this tool provides a geometric view of the detector location and raw data collected from each detector.

New features in DAVE 1.4

As with previous stable releases, there have been numerous upgrades to DAVE in version 1.4 as well as the introduction of new application modules. Some of the more notable changes includes the following modules (click on the hyperlinks to view a brief description): DCS Data Reduction, TAS Data Reduction, NSE Data Reduction, Peak Analysis, TAS Scan Mapper, ResCal, Gaussian98/03 Viewer, MARS Data Reduction, Mars User Registration, MARS Experiment Planner, MARS Batch, MARS Status, MARS Diffraction Banks Calibration, MARS Analyser Banks Calibration, FOCUS Batch .

DCS Data Reduction

Menu location: Data Reduction => NCNR => DCS => GUI:DCS Reduction

An overhaul of the original DCS data reduction program. This version is more user friendly and is also faster.

TAS Data Reduction

Menu location: Data Reduction => NCNR => TAS => TAS data reduction

Upgrade TAS data reduction to include full support for the BT7 intermediate data format generated by the new ICE instrument control software. Update the monitor and resolution correction procedures for BT7, BT9 and SPINS instrument.

NSE Data Reduction

Menu location: Data Reduction => NCNR => NSE => Reduce NSE data

Upgrades to Spin Echo data reduction to include support for magnetic systems and diffraction.

Peak Analysis and RAINS

Menu location: Data Analysis => PAN (Peak Analysis)

Menu location: Data Analysis => RAINS

Upgrades to the convolution procedure to make it more general. Independent handling of instrumental resolution and experimental data and improve how each can be independently constrained or modified (crop, rebin etc).

TAS Scan Mapper

Menu location: Planning => TAS Tools => TAS Scan Mapper

This program computes and displays TAS scan trajectories in reciprocal space produced by the primary beam, harmonics from the monochromator and analyzer, and incoherent scattering from the monochromator and analyzer. It maps out reciprocal space, highlights positions in a scan which may give rise to spurious features, and it displays their likely origin.


Menu location: Planning => TAS Tools => Rescal2

ResCal uses the Cooper-Nathans approach to calculate the resolution ellipse for a triple axis spectrometer in three different planes. The program provides a simplified user interface for visualizing the calculated results.

Gaussian98/03 Viewer

Menu location: Tools => NCNR Tools => FANS Tools => Gaussian98/03 Calculation

This program takes the output log file Gaussian98/03 calculation and converts it into a vibrational spectrum that can be compared with neutron scattering data. It also allows the animation of the vibrational modes of the molecule to be seen (or saved).

MARS Data Reduction

Menu location: Data Reduction => PSI => Reduce MARS Data

Program for the reduction of MARS data. MARS is inverted time-of-flight spectrometer at PSI, Switzerland. The common use of this program is to convert the raw time-of-flight data into S(Q,w).

Mars User Registration

Menu location:Tools => PSI Tools => MARS Tools => MARS User Registration

Allows a user to enter personal details and other information pertaining to an experiment. The information constitutes part of the information written to the data files.

MARS Experiment Planner

Menu location:Tools => PSI Tools => MARS Tools => MARS Experiment Planner

Allows the user to plan experiments for the inverted time-of-flight spectrometer MARS. For a given setting, the user may view the incoming flux, analyser efficiency, resolution, available energy window, and the Q range. To realize a given setting, the choppers phases, analyser scattering angle and histogram memory must be configured. The information can be sent directly to the instrument or stored in a planner file, which may be read and interpreted by the MARS batch program.

MARS Batch

Menu location:Tools => PSI Tools => MARS Tools => MARS Batch

Affords the execution of given experiment. Commands relating to the measurement time, sample environment and instrument settings entered by the user are translated into the language of the server and sent to the instrument. Batch files containing a number of different instrument settings may be easily configured and executed.

MARS Status

Menu location:Tools => PSI Tools => MARS Tools => MARS Status

Displays the current status of the instrument. All hardware parameters may be accessed and the data viewed as it is currently being collected.

MARS Diffraction Banks Calibration

Menu location:Tools => PSI Tools => MARS Tools => MARS Diffraction Banks Calibration

Program to assist in calibrating the angles and distances of the diffraction detectors.

MARS Analyser Banks Calibration

Menu location:Tools => PSI Tools => MARS Tools => MARS Analyser Banks Calibration

Program to assist in deriving the correct motor positions of the moveable analyser banks.


Menu location:Tools => PSI Tools => FOCUS Tools => FOCUS Batch

This program is akin to MARS batch, but written for the direct geometry time-of-flight spectrometer FOCUS.

New features in DAVE 1.3

In this release, many of the existing applications within DAVE have undergone a significant overhaul. The changes have been geared towards improved stability, better accuracy, user interface enhancements and the implimentation of missing features. In addition, several new application modules were introduced in the current release such as NSE Data Reduction, Reflectometry Software, FOCUS Data Reduction, etc. A brief summary of the main features of the new modules follows.

NSE Data Reduction

Menu location: Data Reduction => NSE => NSE Data Reduction

This module is used to reduce Neutron Spin Echo data and provide some basic analysis capabilities for the reduced I(Q,t). Some key features are:
  1. Input, data interaction, fitting
    • Simplified tree widget interface provides clear organization and easy access to multiple files.
    • Multiple plotting and image options provide easy inspection and interaction with the data (e.g. image visualizations of key fitting and data parameters; plot visualizations of echo curves and fit parameters.)
    • Multiple convenient and flexible ways to fit and refit the echo curves, (e.g. graphical interactions
  2. Output
    • DAVE format (for use in other DAVE modules, e.g. PAN)
    • ASCII text formats (compatible with earlier Igor reduction programs).
  3. Experimental Support
    • Initial views of incomplete scans
    • Preliminary calculation of S(Q,0) and S(Q,t) (with or without resolution and background scans)
    • Basic calculations for instrument characterization (e.g. average width calculations)

Reflectometry Software

Menu locations:Data Reduction => REFLECTOMETRY => Reduce reflectometry data
Data Analysis => Reflectometry Analysis => ReflFit Nonpolarized Reflectivity Analysis
Data Analysis => Reflectometry Analysis => ReflPol Polarized Reflectivity Analysis

Reduce and analyze reflectivity data.

FOCUS Data Reduction

Menu location:Data Reduction => PSI => Reduce FOCUS data

Reduce data from the FOCUS tof instrument at PSI.

New features in DAVE 1.2

In this release, many of the existing applications within DAVE have undergone a significant overhaul. The changes have been geared towards improved stability, better accuracy, user interface enhancements and the implimentation of missing features. In addition, several new application modules were introduced in the current release such as RAINS, Data Browser, DAVE PEEK, DCS Mslice, ASCII data reader, etc. A brief summary of the main features of the new modules follows.

ASCII data reader

Menu location: Data Reduction => ASCII data => ASCII data->DAVE

This is a flexible module for reading and converting ASCII data into the DAVE data format. Thus enabling the use of the available analysis and visualization application modules within DAVE. Main features include.
  • Supports ASCII files with a single group of three-column: x, z(x), dz(x)
  • And with multiple dimensions/groups: x, y, z(x,y), dz(x,y)
  • Transforms the ASCII datasets into the DAVE data format.
  • Easy-to-use tree view ASCII file browser.
  • Can assign relevant sample information, useful for combining files in a parametric study.

Data Browser

Menu location: Visualization => Data Browser

The Data Browser is intended to fulfill the data visualization requirements within DAVE in addition to some basic data analysis tasks. The list of capabilities is long but can be summarized under the following groupings.
  1. Input/Output
    • Read/write DAVE format files. Multiple datasets can be handled simultaneously
    • Print and save output plots/images in a variety of formats (ps,jpeg,png,bmp,tiff)
  2. Data Operations
    • Rebin, scale, and add a scaler to individual datasets
    • Make 1D slices/cuts of 2D data
    • Merge/combine multiple 1D/2D datasets into a single 2D dataset
    • Make copies of datasets, extract spectra and edit sample information
  3. Visualization
    • Create multi-line plots from one or more 1D datasets.
    • Create contour/image/surface plots from a 2D dataset.
    • Fully customizable plot attributes such as linestyle, symbol, color, fonts, axes labels, title, legends, color tables (2D), data display ranges, etc.
    • Context-sensitive menus improves ease of use; only valid menu options are shown when a user right-clicks on an editable plot item.
    • Quick mouse (rubber-band) zooming and window resizing.
    • Multiple views of the same data.
    • All views are updated if/when the data they depend on changes.
    • View current treatment information for all datasets.
    • View/modify sample information.


Menu location: Visualization => DAVE PEEK

This application is a DAVE clone of XPEEK and is useable only when DAVE is run locally within the NCNR. DAVE PEEK displays "real-time" data from those instruments that use ICP for their data acquisition. This is a simple viewer that displays the current data from any of the ICP instruments. In addition, the data being displayed can be made available to the modules within DAVE.

DCS Mslice

Menu location: Data Reduction => DCS => DCS Mslice

DCS Mslice is a DAVE clone of the original MATLAB Mslice program. Almost all the capabilities of the original program have been ported over and many new ones added. Mslice is well suited to the visualization of time-of-flight neutron inelastic scattering data in general, especially for single crystal data where most other visualization programs would be inadequate. The main features include the following.
  • Three modes of operation: powder, single crystal or diffuse scattering
  • Background subtraction, detector efficiency correction, detector masking and intensity normalization.
  • Color contour plots or surface plots of slices of S(Q,w) or symmetrized S(Q,w).
  • Flexible plotting and overplotting of cuts.
  • Arbitrary number of plotting windows.
  • Direct exporting of 1D cuts to PAN for fitting.


Menu location: Data Analysis => RAINS

RAINS (Refinement Application for Inelastic Neutron Scattering) is a least-squares fitting application which fits 2D model functions to 2D data. Thus minimization of the fitted parameters is performed globally using ALL the available 2D data. The main features of this application module include the following.
  • Easy-to-navigate interface.
  • Interrupt fitting and save parameters at current iteration.
  • Instrumental resolution function included in fits.
  • Impose constraints on fit parameters.
  • Select any range (in either independent variable) over which to fit data.
  • Fit different models to the same data set and compare chisquare values.
  • Several 2D model functions are included. New ones will be added at request of users.

If you reduced, analyzed or visualized your data using DAVE, please acknowledge its use by including the following reference:

[1] DAVE: A comprehensive software suite for the reduction, visualization, and analysis of low energy neutron spectroscopic data, R.T. Azuah, L.R. Kneller, Y. Qiu, P.L.W. Tregenna-Piggott, C.M. Brown, J.R.D. Copley, and R.M. Dimeo, J. Res. Natl. Inst. Stan. Technol. 114, 341 (2009).


This software was developed at the National Institute of Standards and Technology at the NIST Center for Neutron Research by employees of the Federal Government in the course of their official duties. Pursuant to title 17 section 105* of the United States Code this software is not subject to copyright protection and is in the public domain. The DAVE software package is an experimental neutron scattering data reduction, visualization, and analysis system. NIST assumes no responsibility whatsoever for its use, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic. The use of certain trade names or commercial products does not imply any endorsement of a particular product, nor does it imply that the named product is necessarily the best product for the stated purpose. We would appreciate acknowledgment if the software is used.

*Subject matter of copyright: United States Government works

Copyright protection under this title is not available for any work of the United States Government, but the United States Government is not precluded from receiving and holding copyrights transferred to it by assignment, bequest, or otherwise.


This work is based upon activities supported by the National Science Foundation under Agreement No. DMR-0944772 (previously DMR-0454672 for period 2005 to 2010).

The DAVE development team consists of Richard Azuah, John Copley, Rob Dimeo, Sungil Park, Seung-Hun Lee, Alan Munter, Larry Kneller, Yiming Qiu, Inma Peral, Craig Brown, Paul Kienzle and Philip Tregenna. Additional open source utilities written by David Fanning, Ronn Kling, Mark Piper, Michael D. Galloy, and Craig Markwardt have been incorporated into some of the DAVE programs as well.

Last modified 14-September-2010 by website owner: NCNR (attn: Richard Azuah)