Added d space unit in A

pyFAI/gui/utils/test/test_unitutils.py

@@ -50,6 +50,10 @@ def testFrom2ThRad__Q_A(self):
         result = unitutils.from2ThRad(0.1, units.Q_A, wavelength=1.03321e-10)
         self.assertAlmostEqual(result, 0.6078, places=3)
 
+    def testFrom2ThRad__RecD_A(self):
+        result = unitutils.from2ThRad(0.1, units.RecD_A, wavelength=1.03321e-10)
+        self.assertAlmostEqual(result, 10.3364, places=3)
+
     def testFrom2ThRad__Q_NM(self):
         result = unitutils.from2ThRad(0.1, units.Q_NM, wavelength=1.03321e-10)
         self.assertAlmostEqual(result, 6.0786, places=3)

pyFAI/gui/utils/unitutils.py

@@ -116,6 +116,9 @@ def from2ThRad(twoTheta, unit, wavelength=None, directDist=None, ai=None):
         else:
             beamCentre_m = ai.getFit2D()["directDist"] * 1e-3  # convert in m
         return beamCentre_m * numpy.tan(twoTheta) * unit.scale
+    elif unit.space == "d":
+        q_m = (4.0 * numpy.pi / wavelength) * numpy.sin(0.5 * twoTheta)
+        return (2 * numpy.pi / q_m) * unit.scale
     elif unit.space == "d*2":
         rec_d2_nm = (2e-9 / wavelength * numpy.sin(0.5 * twoTheta)) ** 2
         return rec_d2_nm * unit.scale

pyFAI/units.py

@@ -192,8 +192,9 @@ def eq_q(x, y, z, wavelength):
 formula_r = "sqrt(x * x + y * y)"
 formula_2th = "arctan2(sqrt(x * x + y * y), z)"
 formula_chi = "arctan2(y, x)"
-formula_q = "4.0e-9*π/λ*sin(arctan2(sqrt(x * x + y * y), z)/2.0)"
-formula_d2 = "(2.0e-9/λ*sin(arctan2(sqrt(x * x + y * y), z)/2.0))**2"
+formula_q = "4.0e-9*π/λ*sin(0.5*arctan2(sqrt(x * x + y * y), z))"
+formula_d = "0.5*λ/sin(0.5*arctan2(sqrt(x * x + y * y), z))"
+formula_d2 = "(2.0e-9/λ*sin(0.5*arctan2(sqrt(x * x + y * y), z)))**2"
 formula_qx = "4.0e-9*π/λ*sin(arctan2(x, z)/2.0)"
 formula_qy = "4.0e-9*π/λ*sin(arctan2(y, z)/2.0)"
 
@@ -256,6 +257,30 @@ def eq_q(x, y, z, wavelength):
                      short_name="q",
                      unit_symbol=r"\AA^{-1}")
 
+register_radial_unit("d_m",
+                     scale=1,
+                     label=r"d-spacing $d$ ($m$)",
+                     equation=lambda x, y, z, wavelength: ((2.0 * numpy.pi) / (1e9 * eq_q(x, y, z, wavelength))),
+                     formula=formula_d,
+                     short_name="d",
+                     unit_symbol=r"m")
+
+register_radial_unit("d_nm",
+                     scale=1e9,
+                     label=r"d-spacing $d$ ($nm$)",
+                     equation=lambda x, y, z, wavelength: ((2.0 * numpy.pi) / (1e9 * eq_q(x, y, z, wavelength))),
+                     formula=formula_d,
+                     short_name="d",
+                     unit_symbol=r"nm")
+
+register_radial_unit("d_A",
+                     scale=1e10,
+                     label=r"d-spacing $d$ ($\AA$)",
+                     equation=lambda x, y, z, wavelength: ((2.0 * numpy.pi) / (1e9 * eq_q(x, y, z, wavelength))),
+                     formula=formula_d,
+                     short_name="d",
+                     unit_symbol=r"\AA")
+
 register_radial_unit("d*2_A^-2",
                      center="rd2Array",
                      delta="deltaRd2",
@@ -390,6 +415,7 @@ def to_unit(obj, type_=None):
 TTH_DEG = TTH = RADIAL_UNITS["2th_deg"]
 R = R_MM = RADIAL_UNITS["r_mm"]
 R_M = RADIAL_UNITS["r_m"]
+RecD_A = RADIAL_UNITS["d_A"]
 RecD2_NM = RADIAL_UNITS["d*2_nm^-2"]
 RecD2_A = RADIAL_UNITS["d*2_A^-2"]
 l_m = LENGTH_UNITS["m"]