• Intro
• Highlights
• Features
• Setup
• Analysis
• Display

Data Analysis: Advanced calculations, measurements, data extraction, application specific tools and more.

To experience a selection of LabChart's data analysis features, download this rabbit ECG data file ( 76 KB ). The file can be opened in LabChart or LabChart Reader. LabChart Reader is available as a free download.

Analysis Manager

The Analysis Manager is supported by the latest version of popular LabChart Modules and LabChart alone. It allows you to save and recall:

• A selection of data and its horizontal position in Chart and Scope Views.
• An active point and its horizontal position in Chart and Scope Views.
• Settings from Module settings dialogs.
• One or more regions of analysed data and the horizontal location in Chart and Scope Views.
• Multiple analyses of the same or different regions made with modules.
• Selections from the Module menu (i.e. 'show cycle markers').
• Selections made in a module view or table (i.e. regression information, parameters displayed).

   Watch the Analysis Manager video tutorial

Spectrum View

The Spectrum View is a powerful tool to display and analyze the component frequencies of a signal.  The spectral analysis is represented graphically with the Power Spectral Density (PSD) and the Spectrogram plot. The PSD and Spectrogram panes can be displayed individually or together, in online or offline modes. You can view PSD traces in separate panes (stacked) or overlay the traces for quick and easy comparison.

Spectrum is frequently used to isolate electrical noise components or distinguish component waveforms within a signal such as Alpha, Beta, Delta, Theta and Gamma waveforms within an EEG.

Power Spectral Density (PSD)
PSD displays the power of the input signal over a selected frequency range.  Single or multiple signals can be analyzed. Data from multiple channels are overlaid on the PSD plot. The example above shows two signals being represented in red and blue. 
Spectrum View settings allow the selection of:

• The size of FFT calculations, which affects the frequency resolution.
• The type of data window, reduce artifacts due to non-periodic data.
• The extent of window overlap to increase the accuracy
• Amplitude zeroing of the first frequency component.

Several PSD display modes are available, including:

• Amplitude
• Power
• Power Density
• Power Attenuation (decibels)
• Stacked or overlaid PSD traces.

Spectrogram
The Spectrogram displays a false colour coded plot of signal spectral power against time and frequency.  Separate Spectrogram plots are used to display each selected channel.  You can easily select the colour scale of the Spectral power trace.

Spectrum parameters can be continuously displayed as signal in LabChart using Channel Calculations. Parameters of interest can be also periodically exported the Data Pad.

Analyzing Data with Data Pad

Online:

Raw signals or calculated values from any channel can be extracted and logged into a table using the Data Pad, powered by the ADInstruments Spreadsheet Engine. Designed and purpose-built by ADInstruments software architects it features parallel processing and full Unicode support for unmatched speed in data logging, analysis and export. The number of Data Pad rows is unrestricted, and you can add multiple sheets of data for analysis.

You can automate the addition of values prior to recording by using the 'Timed Add to Data Pad' feature. This feature periodically logs extracted parameters to the Data Pad while data is recorded. 'Timed Add to Data Pad' in conjunction with LabChart OLE linking allows real time plotting of X-Y curves in Excel for qualitative linear regression analysis.

Offline:

You can also select the data of interest after it has been recorded by simply choosing the 'Add to Data Pad' command. The 'Multiple Add to Data Pad' feature can also repeatedly extract values from data already recorded.

Data Pad contents can be saved as a text file, Excel file (Win only) or can be copied to other programs. Using OLE you can also export incoming values to Excel and other programs in real time.

Analysis options include:

• Statistics

  - calculate the mean, SD, RMS, max and min value, time at max and min values and number of points

• Selection & Active Point

  - obtain the start time, end time, duration and number of points

• End Value - Start Value

  - provides the difference between the start and end values of a selection.

• Comments

  - list time or value of active points, comments and comment numbers or times

• Slope

  - get the average slope value, max and min slope or time at max and min slopes

• Integral

  - calculate time integrals online or offline

• Block Information

  - obtain the range, sample interval, block number, block duration, samples in block, start time, start date and sampling rate

• Cyclic Measurements

  - extract periodic parameters from waveforms including frequency, rate mean, min and max, 1/3 max + 2/3 min, height, integral, variance, max and min derivatives

• Scope

  - obtain page number, page duration and page start time containing the active point or selection from Scope View

• XY Loop Calculations

  - calculates the area inside the XY loop, x or y value and slope at the reference point in XY loop, minimum and maximum x or y value, time at minimum and maximum x or y value, and mean of x or y value in XY loop in the XY View

Incoming or already recorded values can be exported in real time using OLE client programs such as Excel and Word. The link from LabChart to Excel can be made dependent so that any change to the data selection in LabChart will automatically update the values in Excel. OLE is available from the LabChart View mode as well as from the Data Pad.

  Download: Timed Add to Data Pad Software Tip(103 KB)

OLE Linking with LabChart for Windows

Incoming or already recorded values can be exported in real time using OLE client programs such as Excel and Word. The link from LabChart to Excel can be made dependent so that any change to the data selection in LabChart will automatically update the values in Excel. OLE is available from the LabChart View mode as well as from the Data Pad.

Finding Data

The Find and Select feature allows you to quickly find specific points of interest within a data file. Set up your required search and selection criteria and search any number of channels for:

• comments
• waveform peaks
• waveform troughs
• block boundaries
• maximum or minimum values
• and more

 

Using the Marker Tool

You can make relative measurements of a waveform with respect to its position by dragging and locking the Marker at a point of interest on the waveform. By moving the cursor along the waveform, on either side of the marker, you can measure and display the relative time and amplitude at the cursor positions.

Channel Calculations

These options let you apply calculations to channels of recorded data online or offline. The following channel calculations are built into LabChart:

• Arithmetic

  - apply equations to channels, including math equations, trigonometric functions, logarithmic functions, noise and filtering functions.

• Cyclic Measurements

  - analyze periodic waveforms to derive functions such as rate, period and frequency as well as cyclic mean, maximum, minimum and height.

• Derivative

  - display the first and second derivative.

• Digital Filter

  - select from six online or offline filter types: low-pass, high-pass, notch, narrow band-pass, band-pass and band-stop.

• Integral

  - measure areas under waveforms.

• Shift

  - shift data backwards or forwards in time.

• Smoothing

  - remove unwanted high frequencies and noise from a waveform.

• Spectrum

  - display Total Power, Percentage Total Power, Maximum and Minimum Power, Maximum and Minimum Power Frequency, Mean Power Frequency, Median Power Frequency, Standard Deviation Frequency and Spectral Edge Frequency.

Cyclic Measurements

Cyclic Measurements allows quick, easy and powerful processing of periodic waveform signals, online or offline, converting raw data from one channel to computed data displayed in another. The advanced detection and available presets allows users to simply select the signal type, drag the slider until all peaks are selected and click ok to start analyzing the the periodic data. The following calculations are available:

• Rate

  - calculate rates e.g. heart rate from ECG.

• Period

  - measure time taken to complete a cycle.

• Frequency

  - calculate event frequencies.

• Mean

  - derive the mean of a cyclic waveform.

• Min, Max, 1/3 Max + 2/3 Min

  - use these, for example, to calculate the diastolic, systolic and mean BP from an arterial BP trace.

• Height

  - calculate maximums minus minimum height.

• Integral

  - measure areas under waveforms.

• Variance

  - detect statistical variance of values within a given cycle of a waveform.

• Min and Max Derivative

  - calculate minimum and maximum derivatives in a given cycle of a waveform.

• Unit Spike at Events

  - place markers on a second channel where a peak occurs on the input channel.

• Event markers now able to be exported separately from comments

  - you now have the choice of exporting event markers separately in the Export as settings dialogs.

Macros

LabChart 7 allows editable macros with VB scripting in both Chart and Scope View. Use the Macro feature to:

• Automate repetitive tasks such as extracting data, exporting data and adding comments
  
• Change recording settings such as sampling rates and stimulus settings for different stages of an experiment

LabChart Extensions

LabChart Extensions are available free of charge to all LabChart users and provide additional data formatting, filtering, visualization, measurement calculations and other utility features.

See the LabChart Extensions page for the complete Extension list for Windows and Macintosh.

Latest additions include:

• Playback File Extension - A powerful virtual recording device that streams data from saved LabChart files (source files) to live LabChart channels. It can be used alone as a single device connected to LabChart), or in combination with a PowerLab unit, to mimic real-time data acquisition. The source file can be streamed at its native sample rate, or resampled at rates commonly used by LabChart.
  Any file that is recognized by LabChart can be used as a source file (including imported file types) such as EDF, MATLAB, WAV, FLAC, OGG and more.
  Any channel calculations present within the source file are generated as source data. As well as allowing aggregation of data for research, is a cost-effective solution for simulating real-time PowerLab sampling in the classroom.
• Integration of Export, Import and Translate Extensions - All Export, Import and Translate extensions (with the exception of Export QuickTime) are bnow available in LabChart as a standard feature. These include:
  • Export IGOR, Export MATLAB, Export WAV
  • Read AcqKnowledge
  • Read WAV, Read WinDAQ
  • Translate Axon, Translate Binary, Translate EDF
• New Read Wav and Read WinDAQ Extensions - Part of the newly integrated Export, Import and Translate extensions, WAV and WinDAQ files can now be imported into LabChart. The filetypes are available from Open dialog in the File drop down menu.

LabChart Modules for Advanced Analysis

LabChart Modules provide specialized data acquisition and analysis features for specific applications.

Blood Pressure Module (Win)	Heart Rate Variability Module (Win or Mac)
Cardiac Output Module (Win)	Metabolic Module (Win or Mac)
DMT Normalization Module (Win or Mac)	Peak Analysis Module (Win)
Dose Response Module (Win)	Spike Histogram Module (Win or Mac)
ECG Analysis Module (Win)	Circadian Analysis Module (Win)
Video Capture Module (Win or Mac)	PV Loop Module (Win)

See the LabChart Modules page for more information, and visit our multimedia page to watch movies detailing the features of several Modules.

For more information, or an obligation-free demonstration of the PowerLab data acquisition system including LabChart software, contact your local ADInstruments representative.

Please note that software features may differ between the Windows and Mac OS versions of LabChart. See the Software Updates page for more information on the latest versions.