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 # Project for PWR
-
 Project in python for module "Praktikum Wissenschaftliches Rechnen" in "Applied Mathematics" at *TU Bergakademie Freiberg*.
 
 # Task
-Implement MPI parallel Matrix and Vector classes in Python and apply them to a numerical problem / algorithm.
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+Implement MPI parallel Matrix and Vector classes in Python and apply them to a numerical problem / algorithm.
+1. Diagonalmatrix times vector
+2. Matrix from exercise 1 times vector
+3. Conjugated Gradient
+
+# Structure of mains
+## Timings in Shell
+If you want to measure time with `time` and the whole program, then use the `main_[name].py` files.
+Within the files you can set the size `n` of the matrix and vector.
+See pbs script [pwr_project.script](./pbs_scripts/pwr_project.script) for automatic use on the cluster.
+Following pythin scripts are the entry point for the tasks:
+- [Diagonalmatrix times Vector](./src/main_diag_vec.py): [main_diag_vec.py](./src/main_diag_vec.py)
+- [Matrix from exercise 1 times Vector](./src/main_matrix_vec.py): [main_matrix_vec.py](./src/main_matrix_vec.py)
+- [CG](./src/main_cg.py): [main_cg.py](./src/main_cg.py)
+
+## Specific timings
+If you want to measure only the times a operation needs (without initializing),
+then use the `main_[name]_timeit.py` files.
+The matrix/vector size `n` must be provided via command line, 
+e.g. `python3 main_cg.py 100` for the CG with a matrix size of `100`.
+See pbs script [pwr_project_timeit.script](./pbs_scripts/pwr_project_timeit.script) for automatic use on the cluster.
+Following pythin scripts are the entry point for the tasks:
+- [Diagonalmatrix times Vector](./src/main_diag_vec_timeit.py): [main_diag_vec.py](./src/main_diag_vec_timeit.py)
+- [Matrix from exercise 1 times Vector](./src/main_matrix_vec_timeit.py): [main_matrix_vec.py](./src/main_matrix_vec_timeit.py)
+- [CG](./src/main_cg_timeit.py): [main_cg.py](./src/main_cg_timeit.py)
+
+## Weak scaling
+For the weak scaling measurements use pbs script [pwr_project_timeit_weak.script](./pbs_scripts/pwr_project_timeit_weak.script).
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