Column indexes are always based on 1 everywhere in PhpSpreadsheet.
This is consistent with rows starting at 1, as well as Excel
function `COLUMN()`. It should also make it easier to reason about
columns and rows and remove any doubts whether a specific method is
expecting 0 based or 1 based indexes.
Fixes#273
Fixes https://github.com/PHPOffice/PHPExcel/issues/307
Fixes https://github.com/PHPOffice/PHPExcel/issues/476
When describing a cell, the cell reference (r="A1") is optional.
When not present, we should just increment the index of the last processed row.
Fixes#201Closes#225
When the xml file is not a standard xml file, the `simplexml_load_string` will return false, this will cause an error on "$xml->getNamespaces(true);" . So instead of showing the error, we throw an exception.
By design, UTF-8 allows any byte-oriented substring searching algorithm,
since the sequence of bytes for a character cannot occur anywhere else
([source](https://en.wikipedia.org/wiki/UTF-8#Advantages_3)).
So `str_replace()` also works for UTF-8-encoded strings, assuming that
the input strings are valid UTF-8 strings. The previous implementation
of mbStrReplace() did nothing to detect invalid strings.
Also, `str_replace()` does not support [Unicode equivalence](https://en.wikipedia.org/wiki/Unicode_equivalence),
but nor do the other `mb_string` functions, and nor does `=SUBSTITUTE()` in Excel
(tested on Excel for Mac version 15.19.1, Excel 2016 for Windows and LibreOffice 5.1).
Closes#109
If $a or $b are not strings, you can get an error that fmod needs param 1 ($a) to be of type double.
MS Excel does not fall over when you insert an empty string in MOD, so I'm guessing PHPExcel should do the same?
Adrien Crivelli