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Added
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* Implement LEFT()
* Implement ISERROR()
* Implement FIND()
* Implement ISNUMBER()
* Implement SUMPRODUCT()
* Implement CEILING()
* Implement TRUNC() and FLOOR()
* Add support for LOG()
* Improve ABS(), INT() and ROUND()
* Add quoted_address() method to AddressRange and AddressCell
* Add public interface to get list of formula_cells()
* Add NotImplementedError for "linked" sheet names
* Add reference URL to function info
* Added considerable extensions to CSE Array Formula Support
* Add CSE Array handling to excelformula and excelcompiler
* Change Row, Column & Index to rectangular arrays only
* Add in_array_formula_context
* Add cse_array_wrapper() to allow calling functions in array context
* Add error_string_wrapper() to check for excel errors
* Move math_wrap() to function_helpers.
* Handle Direct CSE Array in cell
* Reorganize CSE Array Formula handling in excelwrapper
* For CSE Arrays that are smaller than target fill w/ None
* Trim oversize array results to fit target range
* Improve needed addresses parser from python code
* Improve _coerce_to_number() and _numerics() for CSE arrays
* Remove formulas from excelwrapper._OpxRange()
Changed
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* Refactored ExcelWrapper, ExcelFormula & ExcelCompiler to allow...
* Refactored function_helpers to add decorators for excelizing library functions
* Improved various messages and exceptions in validate_calcs() and trim_graph()
* Improve Some NotImplementedError() messages
* Only build compiler eval context once
Fixed
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* Address Range Union and Intersection need sheet_name
* Fix function info for paired functions from same line
* Fix Range Intersection
* Fix Unary Minus on Empty cell
* Fix ISNA()
* Fix AddressCell create from tuple
* Power(0,-1) now returns DIV0
* Cleanup index()