9. GSASIIimage: Image calc module

Ellipse fitting & image integration

GSASIIimage.DoPolaCalib(ImageZ, imageData, arcTth)

Determine image polarization by successive integrations with & without preset arc mask. After initial search, does a set of five with offset azimuth to get mean(std) result.

GSASIIimage.EdgeFinder(image, data)

this makes list of all x,y where I>edgeMin suitable for an ellipse search? Not currently used but might be useful in future?

GSASIIimage.Fill2ThetaAzimuthMap(masks, TA, tam, image)

Needs a doc string

GSASIIimage.FitDetector(rings, varyList, parmDict, Print=True, covar=False)

Fit detector calibration parameters

Parameters:

• rings (np.array) – vector of ring positions
• varyList (list) – calibration parameters to be refined
• parmDict (dict) – all calibration parameters
• Print (bool) – set to True (default) to print the results
• covar (bool) – set to True to return the covariance matrix (default is False)

Returns:

[chisq,vals,sigList] unless covar is True, then [chisq,vals,sigList,coVarMatrix] is returned

GSASIIimage.FitMultiDist(rings, varyList, parmDict, Print=True, covar=False)

Fit detector calibration parameters with multi-distance data

Parameters:

• rings (np.array) – vector of ring positions (x,y,dist,d-space)
• varyList (list) – calibration parameters to be refined
• parmDict (dict) – calibration parameters
• Print (bool) – set to True (default) to print the results
• covar (bool) – set to True to return the covariance matrix (default is False)

Returns:

[chisq,vals,sigDict] unless covar is True, then [chisq,vals,sigDict,coVarMatrix] is returned

GSASIIimage.FitStrSta(Image, StrSta, Controls)

Needs a doc string

GSASIIimage.FitStrain(rings, p0, dset, wave, phi, StaType)

Needs a doc string

GSASIIimage.GetAzm(x, y, data)

Give azimuth value for detector x,y position; calibration info in data

GSASIIimage.GetDetXYfromThAzm(Th, Azm, data)

Computes a detector position from a 2theta angle and an azimultal angle (both in degrees) - apparently not used!

GSASIIimage.GetDetectorXY(dsp, azm, data)

Get detector x,y position from d-spacing (dsp), azimuth (azm,deg) & image controls dictionary (data) - new version it seems to be only used in plotting

GSASIIimage.GetDetectorXY2(dsp, azm, data)

Get detector x,y position from d-spacing (dsp), azimuth (azm,deg) & image controls dictionary (data) it seems to be only used in plotting

GSASIIimage.GetDsp(x, y, data)

Give d-spacing value for detector x,y position; calibration info in data

GSASIIimage.GetEllipse(dsp, data)

uses Dandelin spheres to find ellipse or hyperbola parameters from detector geometry as given in image controls dictionary (data) and a d-spacing (dsp)

GSASIIimage.GetEllipse2(tth, dxy, dist, cent, tilt, phi)

uses Dandelin spheres to find ellipse or hyperbola parameters from detector geometry on output radii[0] (b-minor axis) set < 0. for hyperbola

GSASIIimage.GetTth(x, y, data)

Give 2-theta value for detector x,y position; calibration info in data

GSASIIimage.GetTthAzm(x, y, data)

Give 2-theta, azimuth values for detector x,y position; calibration info in data

GSASIIimage.GetTthAzmDsp2(x, y, data)

Computes a 2theta, etc. from a detector position and calibration constants - checked OK for ellipses & hyperbola.

Returns:np.array(tth,azm,G,dsp) where tth is 2theta, azm is the azimutal angle, G is ? and dsp is the d-space

GSASIIimage.GetTthAzmG(x, y, data)

Give 2-theta, azimuth & geometric corr. values for detector x,y position; calibration info in data - only used in integration checked OK for ellipses & hyperbola This is the slow step in image integration

GSASIIimage.GetTthAzmG2(x, y, data)

Give 2-theta, azimuth & geometric corr. values for detector x,y position; calibration info in data - only used in integration - old version

GSASIIimage.ImageCalibrate(G2frame, data)

Called to perform an initial image calibration after points have been selected for the inner ring.

GSASIIimage.ImageCompress(image, scale)

Reduces size of image by selecting every n’th point param: image array: original image param: scale int: intervsl between selected points returns: array: reduced size image

GSASIIimage.ImageIntegrate(image, data, masks, blkSize=128, returnN=False, useTA=None, useMask=None)

Integrate an image; called from OnIntegrateAll and OnIntegrate in G2imgGUI

GSASIIimage.ImageLocalMax(image, w, Xpix, Ypix)

Needs a doc string

GSASIIimage.ImageRecalibrate(G2frame, ImageZ, data, masks, getRingsOnly=False)

Called to repeat the calibration on an image, usually called after calibration is done initially to improve the fit.

Parameters:

• G2frame – The top-level GSAS-II frame or None, to skip plotting
• ImageZ (np.Array) – the image to calibrate
• data (dict) – the Controls dict for the image
• masks (dict) – a dict with masks

Returns:

a list containing vals,varyList,sigList,parmDict,covar or rings (with an array of x, y, and d-space values) if getRingsOnly is True or an empty list, in case of an error

GSASIIimage.Make2ThetaAzimuthMap(data, iLim, jLim)

Needs a doc string

GSASIIimage.calcFij(omg, phi, azm, th)

Uses parameters as defined by Bob He & Kingsley Smith, Adv. in X-Ray Anal. 41, 501 (1997)

Parameters:

• omg – his omega = sample omega rotation; 0 when incident beam || sample surface, 90 when perp. to sample surface
• phi – his phi = sample phi rotation; usually = 0, axis rotates with omg.
• azm – his chi = azimuth around incident beam
• th – his theta = theta

GSASIIimage.checkEllipse(Zsum, distSum, xSum, ySum, dist, x, y)

Needs a doc string

GSASIIimage.makeMat(Angle, Axis)

Make rotation matrix from Angle and Axis

Parameters:

• Angle (float) – in degrees
• Axis (int) – 0 for rotation about x, 1 for about y, etc.

GSASIIimage.makeRing(dsp, ellipse, pix, reject, scalex, scaley, image, mul=1)

Needs a doc string

GSASIIimage.peneCorr(tth, dep, dist)

Needs a doc string

GSASIIimage.pointInPolygon(pXY, xy)

Needs a doc string