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GSoC 2018: Week 11

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GSoC 2018: Week 10

Hello everyone. Here is the brief progress of Rubi module in the 10th week of GSoC period.
Last week, we were able to load all rules. Rubi has now come in a very stable and working condition. One Missing thing in the main PR was missing instructions and documentation. This week I tried my best to write instructions, so that a new user can easily get familiar with it. I have kept it really simple.
Initially, I wrote a script in Mathematica to generate downvalues in separate files. This was done till now manually, but now it's automated. Then I wrote a sympy script to generate all rules and constraints in proper files directly just by running a function. For a more easier understanding of steps, I created `rubi_parsing_guide.md` explaining all steps.
Next thing I realised that it would be good if we create a parsing script for the tests too. Till now I used maple format. But a lot of manual things were required. So I wrote a script which directly parses tests into sympy format. All this…

GSoC 2018: Week 9

Hello everyone. Here is the progress of rubi module in the 9th week of GSoC period.
In the very beginning of the week, the PR for appelf1 was merged. My aim for this week was to load all rules and test at least a small part for each type of rule. Due to the time factor, its not possible to test all. Moreover, rubi needs to be updated to the latest version, so the test suite too will be updated.  
I started with trigo rules. They are huge in number. They were never tested before, so some utility_functions like `TrigReduce`, `KnownTrigIntegrandQ`, `FunctionOfTrig` etc were wrong. They were corrected. Soon I realised a difference between sympy and Mathematica. In mathematica, `1/Cot[x]` is automatically transformed to `Tan[x]` and `1/Tan[x]` too was transformed to `Cot[x]`. But in sympy, these are different. So, `tan(x)` didn't match to `cot(x)` . Francesco suggested to replace all `cot` with `1/tan`  and similarly for `sec` and `csc` (in the code generator too). 
Next, I moved to `i…

GSoC 2018: Week 8

Hello everyone. Here is the brief summary of the progress of rubi integration module in the 8th week of GSoC period.

We completed the testing of logarithmic test cases. Some of the tests are failing as they depend on trigonometric rules. The rules and tests have been updated in this PR.

Next, I loaded all trigonometric rules. They are huge in number. So the loading time increased from 1 min 30 sec to around 6 min. For now, I have not loaded them. I also updated the test cases for parsetools and fixed code quality issues. Currently, the travis is failing due to a bug, which has been fixed in branch 1.2. In the upcoming week, 1.2 probably will get merged in master.

Then I moved on to implementing appellf1 in sympy. Progress can be seen in this PR.

We will be updating our utility_functions to the latest version of RUBI.


GSoC 2018: Week 7

Hello everyone. Here is the brief summary of my work in the seventh week of GSoC period.
Last week, we found a solution for matching `exp` as `Pow`. This week major part was spent in testing exponential rules. Here are some problem faced.
1. UnevaluatedExpr is quite untested and results in recursion errors in many places. like `u = UnevaluatedExpr(E)` now when we want to find imaginary and real part of `u`, using `im(u)`. It causes recursion error. There were other instances too. So in those functions, I replaced them back to `exp`.
2. There was a lot of index error because length of args of a `Pow` object is 2. Whereas for `exp` it's 1. Utility functions used in lot of places `.args[1]`. I found all possible places where arguments of a `Pow` object was accessed using `.args[0] and .args[1]` . I replaced them with `.base` and `.exp`. This solved the problem
There were more minor changes in many utility functions. Currently, I have finished the exponential testing and almost all are pas…

GSoC 2018: Week 6

Here is the brief work done for rubi in the 6th week of GSoC period.

Last week almost 70 % of the miscellaneous algebra was tested. In the start of the week, the miscellaneous algebra testing was completed. The miscellaneous algebra test cases have been pushed in this PR.

After this, I moved on to load exponential rules and test them. While loading the exponential rules, there were some parsing issues. Those were fixed. On start of the testing, it was found that some integrals depend upon the logarithmic and special_function rules. Those too needed to be loaded. There were some undefined or wrongly defined utility_functions like `CancelCommonFactors`, `Gamma (gammainc)`, `PolyGamma`, `ProductLog` and few more small functions. These didn't take much time. I fixed all these.
Soon I realised a major issue of `exp` and `Pow`. Sympy doesn't identify exp as Pow. The rubi rules are defined in such a way that exp needs to be realised as Pow. I tried to process an expression to replace e…

GSoC 2018: Week 5

Hello everyone. Here is the brief summary of my work in the 5th week of GSoC period.
I started this week with testing miscellaneous algebraic test cases. Soon it was found that most test cases depend on rules of `Miscellaneous integration`. So I loaded those rules. There were few new structure in constraints. So parser too was updated for incorporating those. 
While testing, `ExpandIntegrand` did not function well. Matcher used in ExpandIntegrand was of sympy. I changed ExpandIntegrand using replace_all of matchpy. In few more functions I changed the structure using matchpy. In this week, a major part of the time was spent in utility functions. There are many changes. Also some of the test cases of last year was wrong. It gave different result in mathematica. The test cases which I have updated matches with Mathematica's output. I have pushed all changes of utility function in this PR.
Parallely I have also tested around 70 % of miscellaneous algebraic. I will complete the testing…