Add documentation for apply correction algorithm

Refs #10753

Code/Mantid/Testing/Data/DocTest/irs26176_graphite002_cyl_Abs.nxs.md5

+f4b31e993d1747f22074cd17365cf0eb
\ No newline at end of file

Code/Mantid/docs/source/algorithms/ApplyPaalmanPingsCorrection-v1.rst

@@ -15,19 +15,62 @@ in sample), :math:`A_{s,sc}` (scattering in sample and absorption in sample and
 container), :math:`A_{c,sc}` (scattering in container and absorption in sample
 and container) and  :math:`A_{c,c}` (scattering and absorption in container).
 
+This algorithm can be used to apply absorption corrections calculated with
+either the :ref:`algm-CylinderPaalmanPingsCorrection` and
+:ref:`algm-FlatPlatePaalmanPingsCorrection` algorithms as well as the legacy
+indirect calculate correcteions routine, providing that the sample and container
+are first converted to wavelength and the corrections are interpolated to match
+the sample as demonstrated in the example below.
+
 Usage
 -----
 
-**Example:**
+**Example: using with legacy indirect corrections data**
+
+.. testcode:: exSampleAndCanIRISLegacyCorrections
+
+    # Load the sample and can
+    sample_ws = Load('irs26176_graphite002_red.nxs')
+    can_ws = Load('irs26173_graphite002_red.nxs')
+
+    # Convert sample and container workspaces to wavelength
+    sample_ws = ConvertUnits(InputWorkspace=sample_ws,
+                             Target='Wavelength',
+                             EMode='Indirect',
+                             EFixed=1.845)
+    can_ws = ConvertUnits(InputWorkspace=can_ws,
+                          Target='Wavelength',
+                          EMode='Indirect',
+                          EFixed=1.845)
+
+    # Load the corrections workspace
+    corrections_ws = Load('irs26176_graphite002_cyl_Abs.nxs')
+
+    # Interpolate each of the correction factor workspaces to match the
+    # binning of the smaple
+    # Required to use corrections from the old indirect calculate
+    # corrections routines
+    for factor_ws in corrections_ws:
+        SplineInterpolation(WorkspaceToMatch=sample_ws,
+                            WorkspaceToInterpolate=factor_ws,
+                            OutputWorkspace=factor_ws,
+                            OutputWorkspaceDeriv='')
+
+    corr = ApplyPaalmanPingsCorrection(SampleWorkspace=sample_ws,
+                                       CorrectionsWorkspace=corrections_ws,
+                                       CanWorkspace=can_ws)
 
-.. testcode:: exSampleAndCan
+    print 'Corrected workspace has %d spectra over %d bins' % (
+          corr.getNumberHistograms(), corr.blocksize())
 
-    TODO
+    print 'Type of correction applied: %s' % (
+          corr.getRun()['corrections_type'].value)
 
 Output:
 
-.. testoutput:: exSampleAndCan
+.. testoutput:: exSampleAndCanIRISLegacyCorrections
 
-    TODO
+    Corrected workspace has 10 spectra over 1905 bins
+    Type of correction applied: sample_and_can_corrections
 
 .. categories::