Fixes for comments from William Rucklidge

Change-Id: I64fcc25532cc66dc4cb7e2ea7ccfb220b0cb7e1f

docs/source/nnls_modeling.rst

@@ -1777,10 +1777,10 @@ Instances
 .. function:: bool Problem::IsParameterBlockConstant(const double* values) const
 
    Returns ``true`` if a parameter block is set constant, and false
-   otherwise. A parameter block may be set constant in two
-   ways. Either by calling ``SetParameterBlockConstant`` or by
-   associating a ``LocalParameterization`` with a zero dimensional
-   tangent space with it.
+   otherwise. A parameter block may be set constant in two ways:
+   either by calling ``SetParameterBlockConstant`` or by associating a
+   ``LocalParameterization`` with a zero dimensional tangent space
+   with it.
 
 .. function:: void Problem::SetParameterization(double* values, LocalParameterization* local_parameterization)
 

include/ceres/problem.h

@@ -309,10 +309,10 @@ class CERES_EXPORT Problem {
   void SetParameterBlockVariable(double* values);
 
   // Returns true if a parameter block is set constant, and false
-  // otherwise. A parameter block may be set constant in two
-  // ways. Either by calling SetParameterBlockConstant or by
-  // associating a LocalParameterization with a zero dimensional
-  // tangent space with it.
+  // otherwise. A parameter block may be set constant in two ways:
+  // either by calling SetParameterBlockConstant or by associating a
+  // LocalParameterization with a zero dimensional tangent space with
+  // it.
   bool IsParameterBlockConstant(const double* values) const;
 
   // Set the local parameterization for one of the parameter blocks.

internal/ceres/solver_test.cc

@@ -518,17 +518,15 @@ TEST(Solver, ZeroSizedLocalParameterizationHoldsParameterBlockConstant) {
   Problem problem;
   problem.AddResidualBlock(LinearCostFunction::Create(), nullptr, &x, &y);
   problem.SetParameterization(&y, new SubsetParameterization(1, {0}));
-  // Zero dimensional tangent space means that the block is
-  // effectively constant, but because the user did not mark it
-  // constant explicitly, the user will not see it as constant when
-  // querying IsParameterBlockConstant.
   EXPECT_TRUE(problem.IsParameterBlockConstant(&y));
+
   Solver::Options options;
   options.function_tolerance = 0.0;
   options.gradient_tolerance = 0.0;
   options.parameter_tolerance = 0.0;
   Solver::Summary summary;
   Solve(options, &problem, &summary);
+
   EXPECT_EQ(summary.termination_type, CONVERGENCE);
   EXPECT_NEAR(x, 10.0, 1e-7);
   EXPECT_EQ(y, 1.0);