Triple Axis Commands

Contains a list of commands relevant to triple axis instruments.

AcceptLattice

Brief Description

Accepts the calculated lattice constant from the last findpeak if available .

Full Command Path

Usage: AcceptLattice [h] [k] [l]

Usage: AcceptLattice A B C

Positional Arguments

[h] [k] [l] are the hkl values. Parameters of the sample lattice will be set as follows:

  • A will be set equal to [h]*[lattice constant]/[length]

  • B will be set equal to [k]*[lattice constant]/[length]

  • C will be set equal to [l]*[lattice constant]/[length]

  • [length] is the square root of the sum of squares of [h], [k], and [l]

Alternatively, the user specify combination of symbols A, B and C as parameter of AcceptLattice. A B C refer to lattice vectors A, B and C. The corresponding parameter(s) of the sample lattice will be redefined to the lattice constant determined by the last findpeak command.

CalcLattice

Brief Description

Calculate lattice constant from the last findpeak if available. Assumes a cubic lattice.

Full Command Path

CalcLattice

CheckFit

Brief Description

Performs curve fitting to the specified data file.

Full Command Path

Usage: CheckFit [FILE]

[FILE] is a two-column data file.

CorrectLattice

Brief Description

Redefines lattice parameters a,b and/or c based on the results of the last peak scan on A4 or A3/A4. Typically this command is queued right after a peak scan is initiated to automatically changed the lattice constants. NOTE: At least one peak scan on A3 or A3/A4 must have been run since the server started or else this command will fail.

Full Command Path

Usage: Correct Lattice [Coefficient] -a -b -c

Positional Arguments

[Coefficient] scales the value to which the lattice parameters are redefined.

Keyword Arguments

-a If present, lattice parameter a will be redefined (Optional)

-b If present, lattice parameter a will be redefined (Optional)

-c If present, lattice parameter a will be redefined (Optional)

Comment

Brief Description

Appends a comment to a current data file.

Full Command Path

Usage: Comment [comment]

[comment] is a string that contains information that has to be written into a data file.

DefineBragg

Brief Description

Sets the position of the [ThetaDevice] so that it is equal to half of the position of the [TwoThetaDevice].

Full Command Path

Usage: DefineBragg [TwoThetaDevice] [ThetaDevice]

Positional Arguments

[TwoThetaDevice] is the value set the Two Theta device to.

[ThetaDevice] is the value set the Theta device to.

DisableUBMode

Brief Description

Disables UB Matrix mode.

Full Command Path

Usage: DisableUBMode

No arguments.

EnableUBMode

Brief Description

Enables UB Matrix mode.

Full Command Path

Usage: EnableUBMode

No parameters.

GetNewLattice

Brief Description

Returns FindPeak lattice conversion value. Values lesser than zero indicate that lattice parameter has not been set.

Full Command Path

Usage: GetNewLattice

No arguments.

Home

Full Command Name

Instrument Action Home

Instrument

In addition to general instrument commands, the following commands can be used to view and modify triple-axis instrument state.
Instrument Getana
Instrument Getanaspacing
Instrument Getmono
Instrument Getmonospacing
Instrument Setanaspacing
Instrument Setmonospacing

Instrument GetAna

Brief Description

Gets the analyzer information for the instrument.

Syntax

Instrument GetAna

Instrument GetAnaSpacing

Brief Description

Prints the analyzer d-spacing (measured in Angstrom).

Syntax

Instrument GetAnaSpacing

Instrument GetMono

Brief Description

Gets the monochromator information for the instrument.

Syntax

Instrument GetMono

Instrument GetMonoSpacing

Brief Description

Outputs the monochromator d-spacing (measured in Angstrom).

Syntax

Instrument GetMonoSpacing

Instrument SetAnaSpacing

Brief Description

Sets the analyzer d-spacing (measured in Angstrom).

Syntax

Instrument SetAnaSpacing Value

Required Parameters

Value is the number to be set for the analyzer d-spacing

Instrument SetMonoSpacing

Brief Description

Sets the monochromator d-spacing (measured in Angstrom).

Syntax

Instrument SetMonoSpacing Value

Required Parameters

Value is the number to be set for the monochromator d-spacing.

MoveBragg

Brief Description

Moves two devices together to preserve the Bragg condition.

Syntax

MoveBragg TwoThetaDevice TwoThetaPosition ThetaDevice

Required Parameters

TwoThetaDevice is a name of the device representing the two-theta device.

TwoThetaPosition is a float representing the target position of TwoThetaDevice.

ThetaDevice is a name of the device that will be moved together with TwoThetaDevice by a ratio 1:2.

Examples

MoveBragg A4 41 A3

Drives angle A4 to 41 degrees and angle A3 to Pos3 + (41 - Pos4)/2, where Pos3 and Pos4 are current locations of angles A3 and A4, respectively.

Additional Information

See also: Move.

Execution behavior: Queued.

Q

Brief Description

Drives angles A1 through A6 to given energy and HKL positions. Note that lattice and orientation parameters are determined by previously executed Sample and Scan commands.

Full Command Path

Q [Et Etype Efixed] H K L

Required Parameters

H is a value defining a point in reciprocal space.

K is a value defining a point in reciprocal space.

L is a value defining a point in reciprocal space.

Optional Parameters

Et is a value for the energy transfer.

Etype is either i or f specifying that initial(i) or final(f) energy is fixed.

Efixed is a value for the selected energy.

Examples

Q 0.5 i 14.7 1 0 0

Drives angles A1 through A6 to Q-vector (1, 0, 0), incident energy 14.7 meV and energy transfer 5 meV.

Qscan

Brief Description

Start a Q scan, keeping current Ei and Ef as they are

Full Command Path

Usage: QScan [h_i] [k_i] [l_i] [h_f] [k_f] [l_f] [monitor counts] [h step] [k step] [l step]

Positional Arguments

  • [h_i], [k_i], and [l_i] .  are the initial reciprocal lattice points for the scan.

  • [h_f], [k_f], and [l_f] .  are the final reciprocal lattice points for the scan.

  • [monitor counts] .  is the number of monitor counts to count per point.

  • [h step], [k step], and [l step] .  are the step sizes in each reciprocal lattice direction for the scan.

Sample

Sample GetDescr
Sample GetLattice
Sample GetOrient
Sample Info
Sample SetDescr
Sample SetLattice
Sample SetOrient

Sample GetDescr

Brief Description

Retrieves sample description if it is available.

Syntax

Sample GetDescr

Sample GetLattice

Brief Description

Displays parameters of the crystal lattice of the sample in the console.

Syntax

Sample GetLattice

Sample GetOrient

Brief Description

Displays the current orientation vectors in the console.

Syntax

Sample GetOrient

Sample Info

Brief Description

Display in the console the information about sample including sample orientation, lattice and description.

Syntax

Sample Info

Sample SetDescr

Brief Description

Changes sample description.

Syntax

Sample SetDescr Description

Required Parameters

Description is a string describing a sample.

Sample SetLattice

Brief Description

Sets or modifies parameters that determine the structure of the crystal lattice of the sample.

Syntax

Sample SetLattice [options] -A [A] -B [B] -C [C] -Alpha [Alpha] -Beta [Beta] -Gamma [Gamma]

Options
-A A

Specifies first lattice constants.

-B B

Specifies second lattice constants.

-C C

Specifies third lattice constants.

-Alpha Alpha

Specifies angle between lattice vectors.

-Beta Beta

Specifies angle between lattice vectors.

-Gamma Gamma

Specifies angle between lattice vectors.

Sample SetOrient

Brief Description

Sets or modifies the sample orientation vectors which define the scattering plane.

Syntax

SetOrient H1 K1 L1 H2 K2 L2

Required Parameters

H1, K1, L1 describe the first Q-vector, H2, K2, L2 describe the second Q-vector defining the scattering plane.

Scan

Scans are described as an instrument state or a sequence of states at which measurements are made. Virtual devices and sample environment devices can be used in scan description just like any other device.

The following commands can be used to do manipulations on scans and scan lists. Scan AppendList
Scan Automon
Scan ChkOverwrite
Scan ClearList
Scan CurrentToList
Scan Delete
Scan DeleteIndex
Scan Descr
Scan DescrToList
Scan DryRun
Scan FromFile
Scan Howlong
Scan InitScan
Scan List
Scan ListBackup
Scan ListCopy
Scan ListDescr
Scan Load
Scan LoadList
Scan Modify
Scan Operation
Scan Progress
Scan Resume
Scan Run
Scan ScanOn
Scan Set
Scan SetPoint
Scan Stop
Scan ThinLoad

Scan Descriptions

A string describing a scan is used to transfer the scan information between processes. This string is parsed and translated into a sequence of instrument states.

In some cases, additional parameters might be needed for the scan description to be complete. For example, when defining a scan in terms of Q and E, the following parameters have to be included in the description:

  1. Choice of fixed energy: initial (monochromator) or final (analyzer)

  2. Value of fixed energy [meV]

  3. Energy transfer list or initial value (the convention is E = Einitial – Efinal) [meV]

  4. H, K and L list or initial value

In addition, some scans might require server parameters to be set. For example, a scan defined in terms of Q and E will require the following server parameters to be set already:

  1. Monochromator and analyzer d-spacings [Å]

  2. Two orientation vectors

  3. Lattice parameters (a, b, c, α, β, γ)

Example: Scan:Title=”QA4”:Fixed=0:FixedE=14.7:CountType=Time:Counts=10: Npts=5:Range=E=0.1 0:Range=Q=1~0~0 0~0.1~0:Range=A4= 21 1

The description string should always start with the word Scan. Colons separate tokens and values in a list are separated by a space. Each token is made of a field descriptor following by an equal (=) sign and one or several values. The list of available field descriptors is:

  1. Title:  Title of the scan.

  2. Type:  Scan type. Can be supplied as an integer or a string. See below for discussion.

  3. Fixed:  Sets the energy to fix: 0=monochromator, 1=analyzer.

  4. FixedE:  Sets the value of the fixed energy [meV].

  5. Counts:  The number of counts for the point.

  6. CountType:  The device that will be used to count.

  7. DetectorType:  The device that will be used to accumulate the data. This tag only needs to be supplied to select the data to be sent to Xpeek and to specify meta data in the data file. No information will be lost by omitting this tag.

  8. Prefac:  Gives a multiplication factor for the number of counts.

  9. Npts:  The number of points in the scan.

  10. Range:  The functional relation between the scan points for a given device. The format is Range=[device name]=[central position] [increment]. Alternatively, it is possible to define a scan range the following way: Range=[device name]=[start] [stop] S. An “S” at the end of the string indicates that we are using start and stop positions. An I at the end means that the scan specifies initial, step, number of points.

    The Range token can be used to specify any value, including Q and E. Values that are constant throughout the scan can also be specified with a zero increment.

  11. Dev:  As an alternative to Range, the complete list of values to be visited can be supplied: Dev=[device name]=value1 value2 value3…

  12. Timeout:  Time after which the preset counter will be stopped regardless of whether it has reached its preset value.

  13. HoldPoint:  Holding time before the preset counter is started at each point.

  14. HoldScan:  Holding time before the preset counter is started for the first point of a scan.

  15. Npts2:  Number of points of the second dimension in a 2D scan.

  16. Range2:  The functional relation between the scan points for a given device used in the second dimension of a 2D scan.

  17. Comment:  The user can enter a comment here.

  18. Filename:  Specifies a string to be added at the beginning of the data file name.

Any additional tokens can be appended to the scan description as meta data. These additional tokens must be separated by colons.

The Scan List

Scans in ICE are stored in a list in memory. The scan descriptions contained in the list are available to users to run on an instrument. In order to save scans for repeated uses over time, the scan list must be backed up to disk. Several commands exist for manipulating the scan list and moving its contents to and from disk.

Scan AppendList

Brief Description

Appends scans from a given file to the scan list.

Note that this can lead to entries in the current scanlist being overwritten. Use Scan ChkOverwrite to see which scans would be overwritten.

Syntax

Scan AppendList Filename [option]

Required Parameters

Filename is the name of the file content of which will be appended to the scan list.

Options

-K

Prevents scans from being overwritten.

Scan Automon

Brief Description

Estimates the number of monitor counts needed to make the scan run for a given amount of time. This function uses SCAN HOWLONG and scales the monitor counts according to the desired running time.

The Rate command should be run before Scan Automon. If it has not been run when Scan Howlong is run, it will be run automatically before a result is given, unless a scan is in progress, in which case the command will fail.

Syntax

Scan Automon Duration Scanname [options]

Required Parameters

Duration is a whole number of hours.

Scanname is a name in the scan list.

Options

-s

will cause the result to be basaed on a time in seconds.

-o Overhead

sets a default overhead to add to the time for each point. The overhead is in seconds. If there is a device with a higher overhead than the specified overhead, then that device's overhead will be added instead.

Scan ChkOverwrite

Brief Description

Returns the list of scans which would be overwritten by loading a list of scans from a file. See also Scan LoadList and Scan AppendList commands.

Syntax

Scan ChkOverwrite Filename

Required Arguments

Filename is the name of the file to check for conflicts which would overwrite the current scan list.

Scan Clearlist

Brief Description

Clears out all scans currently in the scan list. If those scans have not been backed up, they will be lost.

Syntax

Scan ClearList

Scan CurrentToList

Brief Description

Puts the current scan description in the scan list on the server under a specified name. Note that if a target scan already exists in the list, it will be replaced.

Syntax

Scan CurrentToList Name

Required Arguments

Name is a name of the scan in the scan list to which the scan should be stored.

Scan Delete

Brief Description

Deletes a given scan from the scan list on the server.

Syntax

Scan Delete Name

Required Parameters

Name is the name of the scan in the scan list which is to be deleted.

Scan DeleteIndex

Brief Description

Deletes the scan list entry at a given list index position.

Syntax

Scan DeleteIndex Index

Required Parameters

Index is an integer representing the location of the item to be deleted in the scan list.

Scan Descr

Brief Description

Returns description of the current scan.

Syntax

Scan Descr

Scan DescrToList

Brief Description

Puts a given scan description into the scan list, under the given name. Note that if a target scan already exists in the list, it will be replaced.

Syntax

Scan DescrToList Name Description

Required Parameters

Name is the name to use for the scan.

Description is a properly formatted scan description.

Scan DryRun

Brief Description

Dry runs a given the current scan by calculating device positions for each point in a scan. Each device position is then checked for validity such as being within preset limits. If scan name not given, dry runs the current scan.

Syntax

Scan DryRun Name

Required Arguments

Name is a scan of interest.

Scan FromFile

Brief Description

Runs a scan taken from an already existing data file. The scan description stored in the data file is loaded and run.

The user can specify a new name for the scan; otherwise the scan will have the same name as in the data file.

Syntax

Scan FromFile Datafile Scanname [options]

Required Parameters

Datafile is a name of the data file to read.

Scanname is a name to give the scan when loaded.

Options

-f

forces scan to be overwritten.

-n

stores the scan on the server without running it.

-d

dry runs the scan (and sets it to the current scan).

Scan Howlong

Brief Description

Computes the duration of a scan. If scan counts against Time, the duration of the scan will be set to the number of counts multiplied by the prefactor.

If scan counts against Monitor counts, a 3rd degree polynomial parameterization of the monitor rate as a function of an instrument-specific device will be used to estimate the rate at each point of the scan. The monitor rate predicted by the parameterization is scaled according to the stored monitor rate and the value of device it was measured at.

The Rate command should generally be run before Scan Howlong. If it has not been run when Scan Howlong for scans using monitor counts is run, Rate will be run automatically before a result is given.

Syntax

Scan HowLong Name [options]

Required Parameters

Name is a name of the scan which duration will be estimated.

Options

-s

Instructs to return the result in seconds. Otherwise it will be in hours.

-o Overhead

Sets a default overhead, in seconds, that will be added to the time for each point. If there is a device with a higher movement overhead than the specified overhead, then that device's overhead will be added instead.

Additional Information

See also: Device GetOverhead and Device SetOverhead commands.

Execution behavior: Immediate.

Scan InitScan

Brief Description

Initializes the current scan and sets it to its first point. If the scan is already running, it will finish processing current point and will be re-initialized.

Syntax

Scan InitScan

Scan List

Brief Description

Retrieves the server’s list of scans.

Syntax

Scan List

Scan ListBackup

Brief Description

Saves the scan list to a file.

Syntax

Scan ListBackup Filename

Required Parameters

Filename is a name of file to which the scan list will be saved.

Additional Information

See also: Scan LoadList command.

Execution behavior: Immediate.

Scan ListCopy

Brief Description

Copy an entry in the scan list pointed by Source into the entry pointed by Destination. Note that if Destination already exists in the list, it will be replaced.

Syntax

Scan ListCopy Source Destination

Required Arguments

Source is a positive integer indicating scan to be copied.

Destination is a positive integer indicating the destination where the scan is to be copied.

Scan ListDescr

Brief Description

Retrieves the description of a given scan from the server.

Syntax

Scan ListDescr Name

Required Arguments

Name is a name of the scan to look for in the scan list.

Scan Load

Brief Description

For given scan name, the system reads the current scan description and appends it to the queue for future execution. The user may change scan description later without altering the already queued scan. The user may load multiple scans with the same name and different descriptions.

Syntax

Scan Load Name

Required Parameters

Name is a positive integer indicating a scan that will be loaded for execution.

Scan LoadList

Brief Description

Replaces the scan list with the list from a given file. See also Scan ListBackup command.

Syntax

Scan LoadList Filename

Required Arguments

Filename is a name of file from which to load scan list.

Scan Modify

Brief Description

Modifies the current scan by setting it to a given scan description.

Syntax

Scan Modify Description

Required Parameters

Description is a properly formatted scan description.

Scan Operation

Brief Description

Allows the user to apply changes to descriptions of several scans at once. This command will replace the values of specified scan parameters in the scan description with the values given by the user. If a certain scan parameter has not yet been defined for given scans, the parameter will be added.

Note that this command is intended for advanced users. The system will not prevent you from making changes which lead to invalid or inconsistent scans. See "Notes and Warnings" section below.

Syntax

Scan Operation Name1,Name2,... Changes

Required Parameters

Name1,Name2,... is a list of individual scan names to which changes will be applied. The list should be separated by commas and contain no spaces.

Changes is a list of settings for scan keyword attributes. Each attribute is an attribute name followed by the equals sign and a value. Different attributes are separated by commas. See Scan for definition of scan attributes.

Examples

Scan Operation testscan,realscan Counts=100,Angle=Temp=200

Changes scans testscan and realscan by setting the number of counts to 100 seconds and moving temperature device to 200.

Additional Information

Notes and Warnings: This command does not protect against breaking scans.

See also: scan description format.

Scan Progress

Brief Description

Return the progress percentage for the current scan.

Syntax

Scan Progress

Scan Run

Brief Description

Executes a given scan. Unless Scan Load command was used before Scan Run to copy scan definition to the queue for execution, Scan Run command will use the most recent scan version. Changes made to scan definition after execution begins will not have any effect.

Command Scan Runscan is equivalent to Scan Run.

Syntax

Scan Run [Name]

Optional Arguments

Start is a name of scan that will be executed. If scan name contains spaces, enclose it in double quotes (""). If scan name is not specified, current scan will be run.

Scan Set

Brief Description

Sets current scan to a given scan description.

This command cannot be run if there is a scan in progress.

Syntax

Scan Set Description

Required Parameters

Description is a properly formatted scan description.

Scan SetPoint

Brief Description

Sets the current scan point to a given value.

Syntax

Scan SetPoint Index

Required Parameters

Index is the index of a scan point in the list of scan points for the current scan.

Scan Stop

Brief Description

Schedules to stop the scan after the current point. SCAN NEXTPOINT will no longer work, unless a SCAN RESUME command is issued beforehand.

Syntax

Scan Stop

UB

UB AddPeakSet
UB CalcDestination
UB CalcHKL
UB Calculate
UB DeletePeakSet
UB ExcludePeakSet
UB GetEnergyTolerance
UB IncludePeakSet
UB InvalidatePrimary
UB ModifyPeakSet
UB Print
UB PrintUBMatrix
UB SetEnergyTolerance
UB SetLatticeFixed
UB SetPrimary
UB SetRefPlane

UB AddPeakSet

Brief Description

Adds a new peak set to the UB Matrix. Return value is the ID by which the user may further refer to the submitted peak.

Syntax

UB AddPeakSet H K L A3 A4 LTilt UTilt

Required Parameters

H is H value

K is K value

L is L value

A3 is Sample Theta value

A4 is Sample Two Theta value

LTilt is Lower Tilt value

UTilt is Upper Tilt value

UB CalcDestination

Brief Description

Determines the UB Matrix motor values for a given HKL position.

Syntax

UB CalcDestination H K L

Required Parameters

H is H value

K is K value

L is L value

UB CalcHKL

Brief Description

Back calculates HKL position from user specified positions of Sample Theta (A3), Sample Two Theta (A4) and both sample tilts.

Syntax

UB CalcHKL A3 A4 LTilt UTilt

Required Parameters

A3 is the hypothetical position of sample theta from which to calculate HKL. A4 is the hypothetical position of sample two theta from which to calculate HKL. LTilt is the hypothetical position of lower sample tilt from which to calculate HKL. UTilt is the hypothetical position of upper sample tilt from which to calculate HKL.

UB Calculate

Brief Description

Calculates UB Matrix from input parameters.

Syntax

UB Calculate

UB DeletePeakSet

Brief Description

Removes a peak set with the given ID.

Syntax

UB DeletePeakSet ID

Required Parameters

ID is an identifier returned from UB AddPeakSet command.

UB ExcludePeakSet

Brief Description

Marks a peak set with a given ID for exclusion from future calculations.

Syntax

UB ExcludePeakSet ID

Required Parameters

ID is an identifier returned from UB AddPeakSet command.

UB GetEnergyTolerance

Brief Description

Returns the tolerance for difference between Ei and Ef to calculate UB Matrix. If Ei and Ef differ by more than this tolerance, the UB Matrix cannot be calculated.

Syntax

UB GetEnergyTolerance

UB IncludePeakSet

Brief Description

Marks a peak set with a given ID for inclusion in future calculations.

Syntax

UB IncludePeakSet ID

Required Parameters

ID is an identifier returned from UB AddPeakSet command.

UB InvalidatePrimary

Brief Description

Sets the primary peak set to nothing.

Syntax

UB InvalidatePrimary

UB ModifyPeakSet

Brief Description

Modifies an existing peak set.

Syntax

UB ModifyPeakSet ID [options]

Required Parameters

ID is an identifier returned from UB AddPeakSet command.

Options
-h H

allows to modify H value.

-k K

allows to modify K value.

-l L

allows to modify L value.

-a3 A3

allows to modify A3 value.

-a4 A4

allows to modify A4 value.

-ltilt LTilt

allows to modify LTilt value.

-utilt UTilt

allows to modify UTilt value.

UB Print

Brief Description

Prints an XML string which contains all UB settings, including sample lattice and peak sets.

Syntax

UB Print

UB PrintUBMatrix

Brief Description

Prints the UB Matrix and peakset information that is being used by the server. If no UB Matrix has been computed, then only peakset information is printed.

Syntax

UB PrintUBMatrix

UB SetEnergyTolerance

Brief Description

Sets the tolerance for difference between Ei and Ef to calculate UB Matrix. If Ei and Ef differ by more than this tolerance, the UB Matrix cannot be calculated.

Syntax

UB GetEnergyTolerance Tolerance

Required Parameters

Tolerance is a floating point number which will be set as the new energy tolerance.

UB SetLatticeFixed

Brief Description

Sets the status of lattice parameters as fixed or estimated.

Syntax

UB SetLatticeFixed [options]

Options
-a [f | e]

allows to fix lattice constant a.

-b [f | e]

allows to fix lattice constant b.

-c [f | e]

allows to fix lattice constant c.

-alpha [f | e]

allows to fix lattice angle alpha.

-beta [f | e]

allows to fix lattice angle beta.

-gamma [f | e]

allows to fix lattice angle gamma.

UB SetPrimary

Brief Description

Sets the primary peakset.

Commands

UB SetPrimary ID

Required Parameters

ID is an identifier returned from UB AddPeakSet command.

UB SetRefPlane

Brief Description

Sets the reference plane.

Syntax

UB SetRefPlane Flag

Required Parameters

Flag, if equals A, sets a plane of the first two reflections. If equals B, sets a plane which minimizes the tilts.