Enable overlap region for point data

- and precise release notes
- and add a draft usage example

Refs #22197

Framework/Algorithms/src/Stitch1D.cpp

@@ -564,22 +564,14 @@ void Stitch1D::exec() {
 
   const double intersectionMin = intesectionXRegion.get<0>();
   const double intersectionMax = intesectionXRegion.get<1>();
-
-  double startOverlap;
-  double endOverlap;
-  if (lhsWS->isHistogramData()) {
-    startOverlap = getStartOverlap(intersectionMin, intersectionMax);
-    endOverlap = getEndOverlap(intersectionMin, intersectionMax);
-    if (startOverlap > endOverlap) {
-      std::string message = boost::str(
-          boost::format("Stitch1D cannot have a StartOverlap > EndOverlap. "
-                        "StartOverlap: %0.9f, EndOverlap: %0.9f") %
-          startOverlap % endOverlap);
-      throw std::runtime_error(message);
-    }
-  } else {
-    startOverlap = intersectionMin;
-    endOverlap = intersectionMax;
+  double startOverlap = getStartOverlap(intersectionMin, intersectionMax);
+  double endOverlap = getEndOverlap(intersectionMin, intersectionMax);
+  if (startOverlap > endOverlap) {
+    std::string message = boost::str(
+        boost::format("Stitch1D cannot have a StartOverlap > EndOverlap. "
+                      "StartOverlap: %0.9f, EndOverlap: %0.9f") %
+        startOverlap % endOverlap);
+    throw std::runtime_error(message);
   }
 
   const bool scaleRHS = this->getProperty("ScaleRHSWorkspace");

docs/source/algorithms/Stitch1D-v3.rst

@@ -75,7 +75,7 @@ workspace by this number takes into account its error.
 
 Usage
 -----
-**Example - a basic example using stitch1D to stitch two workspaces together.**
+**Example - a basic example using stitch1D to stitch two histogram workspaces together.**
 
 .. plot::
    :include-source:
@@ -88,7 +88,7 @@ Usage
      """Creates a Gaussian peak centered on mu and with width sigma."""
      return (1/ sigma * np.sqrt(2 * np.pi)) * np.exp( - (x-mu)**2  / (2*sigma**2))
 
-   #create two histograms with a single peak in each one
+   # create two histograms with a single peak in each one
    x1 = np.arange(-1, 1, 0.02)
    x2 = np.arange(0.4, 1.6, 0.02)
    ws1 = CreateWorkspace(UnitX="1/q", DataX=x1, DataY=gaussian(x1[:-1], 0, 0.1)+1)
@@ -109,6 +109,40 @@ Usage
    # uncomment the following line to show the plot window
    #fig.show()
 
+**Example - a basic example using stitch1D to stitch two point data workspaces together.**
+
+.. plot::
+   :include-source:
+
+   from mantid.simpleapi import *
+   import matplotlib.pyplot as plt
+   import numpy as np
+
+   def gaussian(x, mu, sigma):
+     """Creates a Gaussian peak centered on mu and with width sigma."""
+     return (1/ sigma * np.sqrt(2 * np.pi)) * np.exp( - (x-mu)**2  / (2*sigma**2))
+
+   # create two histograms with a single peak in each one
+   x1 = np.arange(-1, 1, 0.02)
+   x2 = np.arange(0.4, 1.6, 0.02)
+   ws1 = CreateWorkspace(UnitX="1/q", DataX=x1, DataY=gaussian(x1, 0, 0.1)+1)
+   ws2 = CreateWorkspace(UnitX="1/q", DataX=x2, DataY=gaussian(x2, 1, 0.05)+1)
+
+   #stitch the histograms together
+   stitched, scale = Stitch1D(LHSWorkspace=ws1, RHSWorkspace=ws2, StartOverlap=0.4, EndOverlap=0.6)
+
+   # plot the individual workspaces alongside the stitched one
+   fig, axs = plt.subplots(nrows=1, ncols=2, subplot_kw={'projection':'mantid'})
+
+   axs[0].plot(mtd['ws1'], wkspIndex=0, label='ws1')
+   axs[0].plot(mtd['ws2'], wkspIndex=0, label='ws2')
+   axs[0].legend()
+   axs[1].plot(mtd['stitched'], wkspIndex=0, color='k', label='stitched')
+   axs[1].legend()
+
+   # uncomment the following line to show the plot window
+   #fig.show()
+
 **Example - a practical example using reflectometry data and a scale factor.**
 
 .. plot::

docs/source/release/v3.13.0/framework.rst

@@ -27,7 +27,7 @@ Improved
 
 - :ref:`Maxent <algm-Maxent>` when outputting the results of the iterations, it no longer pads with zeroes but
   returns as many items as iterations done for each spectrum, making the iterations easy to count.
-- XError values (Dx) can now be treated by the following algorithms: :ref:`ConjoinXRuns <algm-ConjoinXRuns>`, :ref:`ConvertToHistogram <algm-ConvertToHistogram>`, :ref:`ConvertToPointData <algm-ConvertToPointData>`, :ref:`CreateWorkspace <algm-CreateWorkspace>`, :ref:`SortXAxis <algm-SortXAxis>`, :ref:`algm-Stitch1D`.
+- XError values (Dx) can now be treated by the following algorithms: :ref:`ConjoinXRuns <algm-ConjoinXRuns>`, :ref:`ConvertToHistogram <algm-ConvertToHistogram>`, :ref:`ConvertToPointData <algm-ConvertToPointData>`, :ref:`CreateWorkspace <algm-CreateWorkspace>`, :ref:`SortXAxis <algm-SortXAxis>`, :ref:`algm-Stitch1D` (case point data).
 - :ref:`Stitch1D <algm-Stitch1D>` can treat point data.
 - The algorithm :ref:`SortXAxis <algm-SortXAxis>` has a new input option that allows ascending (default) and descending sorting. The documentation needed to be corrected in general.