Merge pull request MRChemSoft#232 from edinvay/one-corner

Updated banded calculations and added an adaptive time evolution operator construction

.github/workflows/build-test.yml

@@ -21,7 +21,9 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        # setup-miniconda not compatible with macos-latest presently.
+        # https://github.com/conda-incubator/setup-miniconda/issues/344
+        os: [ubuntu-latest, macos-12]
 
     steps:
     - uses: actions/checkout@v2
@@ -35,7 +37,7 @@ jobs:
         key:
           ${{ matrix.os }}-conda-${{ env.CACHE_NUMBER }}-${{ hashFiles('.github/mrcpp-gha.yml') }}
 
-    - uses: conda-incubator/setup-miniconda@v2
+    - uses: conda-incubator/setup-miniconda@v3
       with:
           auto-update-conda: true
           auto-activate-base: false
@@ -53,7 +55,7 @@ jobs:
       shell: bash -l {0}
       run: |
         cmake --build build --config $BUILD_TYPE --target install -- -v -d stats
-        
+
     - name: Test
       shell: bash -l {0}
       run: |

docs/programmers_manual/ConvolutionCalculator.rst

@@ -0,0 +1,12 @@
+---------------------
+ConvolutionCalculator
+---------------------
+
+This is an introduction to the ConvolutionCalculator class. We write a small overarching summary of the class where we define the 
+algorithm/equation/structure reasoning for having this class or where it fits with the rest of the code.
+
+.. doxygenclass:: mrcpp::ConvolutionCalculator
+   :members:
+   :protected-members:
+   :private-members:
+

docs/programmers_manual/CornerOperatorTree.rst

@@ -0,0 +1,19 @@
+------------------
+CornerOperatorTree
+------------------
+
+This is an introduction to the CornerOperatorTree class. We write a small overarching summary of the class where we define the
+algorithm/equation/structure reasoning for having this class or where it fits with the rest of the code.
+
+This class inherits from OperatorTree and represents the non-standard form with
+matrices :math:`A, B, C` having negligible matrix elements around their diagonals.
+Note that only these three matrices can be considered narrow banded at the corners,
+and so only for them we redefine the notion of a band width.
+A band of one of them is the distance between the first non-negligible diagonal and the main diagonal.
+
+
+.. doxygenclass:: mrcpp::CornerOperatorTree
+   :members:
+   :protected-members:
+   :private-members:
+

docs/programmers_manual/overview.rst

@@ -17,6 +17,8 @@ TODO: maybe add some low level theory/figures/algorithms before showing classes,
    CrossCorrelationCache
    LegendreBasis
    InterpolatingBasis
+   ConvolutionCalculator
+   CornerOperatorTree
    TimeEvolutionOperator
    JpowerIntegrals
    special_functions

src/functions/JpowerIntegrals.cpp

@@ -39,23 +39,10 @@ JpowerIntegrals::JpowerIntegrals(double a, int scaling, int M, double threshold)
     for(int l = 1 - N; l < 0; l++  )
         integrals.push_back( calculate_J_power_integrals(l, a, M, threshold) );
 }
-/*
-JpowerIntegrals::JpowerIntegrals(const JpowerIntegrals &other)
-{
-    scaling = other.scaling;
 
-    // Copy integrals (deep copy)
-    integrals.clear();
-    for (const auto& row : other.integrals)
-    {
-        std::vector<std::complex<double>> newRow(row);
-        integrals.push_back(newRow);
-    }    
-}
-*/
 
 /// @brief in progress
-/// @param index - in progress
+/// @param index - interger lying in the interval \f$ [ -2^n + 1, \ldots, 2^n - 1 ] \f$.
 /// @return in progress
 std::vector<std::complex<double>> & JpowerIntegrals::operator[](int index)
 {
@@ -83,7 +70,6 @@ std::vector<std::complex<double>> JpowerIntegrals::calculate_J_power_integrals(i
     }
 
     J.erase(J.begin());
-    crop(J, threshold);
     return J;
 }
 

src/operators/HeatKernel.h

@@ -34,7 +34,7 @@ namespace mrcpp {
  *
  * @brief Heat kernel in \f$ \mathbb R^D \f$.
  *
- * @details In $\mathbb R^D$ the heat kernel has the form
+ * @details In \f$ \mathbb R^D \f$ the heat kernel has the form
  * \f[
  *  K_t(x)
  *  =

src/operators/HeatOperator.h

@@ -37,14 +37,14 @@ namespace mrcpp {
  * \f$
  *   \exp \left( t \partial_x^2 \right)
  * \f$
- * can be regarded as a convolution operator in $L^2(\mathbb R)$
+ * can be regarded as a convolution operator in \f$ L^2(\mathbb R) \f$
  * of the form
- * \[
+ * \f[
  *   \exp \left( t \partial_x^2 \right)
  *   f(x)
  *   =
  *   \frac 1{ \sqrt{4 \pi t} }
- *   \int_\R
+ *   \int_{ \mathbb R }
  *   \exp
  *   \left(
  *       - \frac{ (x - y)^2 }{4t}
@@ -53,7 +53,7 @@ namespace mrcpp {
  *   , \quad
  *   t > 0
  *   .
- * \]
+ * \f]
  * 
  */
 template <int D> class HeatOperator final : public ConvolutionOperator<D> {