How to set the alignment, or how to find PyGObject documentation - python-2.7

I am trying to right-align some text content in a CellRenderer. Through several searches I found two approaches, but these do not work. With bold-setting, you need to enable this feature first, so I am guessing I also need to enable alignment setting, but have not found how to do this. This runs without exception:
r = Gtk.CellRendererText()
r.props.width_chars = 10
r.set_property('alignment', Pango.Alignment.RIGHT) # no effect
r.props.alignment = Pango.Alignment.RIGHT # no effect
r.props.weight_set = True # not really needed
r.props.weight = Pango.Weight.BOLD # works, output is bold
This is what I guessed from the bold example but does NOT work:
r.props.alignment_set = True
The error is: 'gi._gobject.GProps' object has no attribute 'alignment_set'
Looking at these references I do not find something on GProps:
GObject Ref Manual
Gtk3 Ref Manual
This resource does say something about alignment, but it is unclear to me how to convert this C code to Python/GObject:
Gnome Gtk3 Manual for C
My question is how to fix this problem, where is the ref manual for this PyGObject error message, or how should I code the right-alignment?
Update:
I am currently looking at this similar SO question for clues.
As for the comment of TingPing, I looked at the set_alignment() method,and tried these:
r.set_alignment(Pango.Alignment.RIGHT) # error: set_alignment() takes exactly 3 arguments (2 given)
r.set_alignment(200, 0) # no error, no effect
besides this method seems intended to create some pixels padding at the left, which is not what I need: align text to the right of the cell space.
Update:
Perhaps the above code is good, but perhaps the CellRenderer() has no intrinsic width, no excess space to put to the left of the content. I thought of this because of thinking of simply left-padding my numberic cell content with spaces. Then I need to decide on the maximum field length. Perhaps the CellRenderer does not 'know' about a default field length. I added a settinge to .props.width_chars, but this did unfortunately not cause any rignt-alignment.

Through this C example I tried this to right-align:
r.props.xalign = 1.0
and it works! The xalign is the fraction of free space 0..1.0 to put to the left of the text. The value 0.5 will center the text.

Related

Extracting number of bits in a macroblock from VVC VTM reference software

Final:Result after calculating and displaying the differenceI am new to VVC and I am going through the reference software's code trying to understand it. I have encoded and decoded videos using the reference software. I want to extract the bitstream from it, I want to know the number of bits there are in each macroblock. I am not sure which class I should be working with, for now I am looking at, mv.cpp, QuantRDOQ.cpp, and TrQuant.cpp.
I am afraid to mess the code up completely, I don't know where to add what lines of code. Start: Result after calculating and displaying the difference
P.S. The linked pictures are after my problem has been solved, I attached these pictures because of my query in the comments.
As the error says, getNumBins() is not supported by the CABAC estimator. So you should make sure you call it "only" during the encoding, and not during the RDO.
This should do the job:
if (isEncoding())
before = m_BinEncoder.getNumBins()
coding_unit( cu, partitioner, cuCtx );
if (isEncoding())
{
after = m_BinEncoder.getNumBins();
diff = after - before;
}
The simpleset solution that I'm aware of is at the encoder side.
The trick is to compute the difference in the number of written bits "before" and "after" encoding a Coding Unit (CU) (aka macroblock). This stuff happens in the CABACWriter.cpp file.
You should go to to coding_tree() function, where coding_unit() function is called, which is responsible for context-coding all syntax elementes in the current CU.
There, you may call the function getNumBins() twice: once before and once after coding_unit(). The difference of the two value should do the job for you.

Apply a function to a range of cells in a spreadsheet

The answers in topics with similar titles haven't given me much of a resolution to my particular problem, but possibly I am not asking the right question. It might help knowing I'm an absolute noob when it comes to spreadsheets, so finding my way around is next to nil.
Currently I can set a basic function in the first cell A1 =ROW()
Simple right? Well now here comes the complication. If I click on the bottom right of the cell and start dragging I can then apply that very same function to a whole range of cells. Let's say I apply it from A1:A10. Every cell within this group now has the same function.
Hooray! We did it, right? I applied a function to a range of cells each with their own output. But wait, if I then go back to the original cell and change its formula none of the other cells change with it. GRRRRR!!!!
There are a couple of fixes I've come up with but don't necessarily know how to implement. The first is to have every cell link back to the original cell and reference its function. This would be useful if I wanted to randomly scatter dependent cells about the document. The other would be much more useful in an orderly group where you know the exact dimensions by specifying in the original cell the size of the array you want to apply the function to.
With that said, let me hear your thoughts.
The closest I've come to an answer is to use FORMULA() which returns the formula used by a cell as text. Unfortunately all answers on evaluating the text resort to scripting. How strange! I thought something like this would be common. Might as well get to scripting.
Hold on, I may have spoke too soon. An array can be made with =MUNIT(), but it's only square. Drats!
Ok... I'm hoping the zebra stripes will eventually become its own answer unless someone else beats me to it. So a simple array can be made with ={1,2;3,4} where commas separate values by column and semicolons for values by row except to generate it you have to press Control+Shift+Enter (because reasons?). I'm thinking now that I'll need to have functions that can generate lists of values based on a single function for each row, and pray that it'll work. So, back to looking. (Wow this is taking forever)
The way I was hypothesizing can't even generate a 1x1, e.g., ={ROW()} returns Err:512 which is a formula overflow.
Alright, in summary so far I've narrowed down the two options,
1) link every cell to the original formula
2) populate an array with a single formula
each with their own incomplete answer,
a) use FORMULA() to return the formula of a cell as text
b) create a hypothetical array like so ={LIST_OF_VALUES()}
These both require a strange form of the nonexistent EVALUATE() function to 'function' correctly. Isn't that fun?
Google Sheets handles case b by allowing ={ROW()}Control+Shift+Enter to generate =ArrayFormula({ROW()}). Working with the general case of any sized array being filled with a single function doesn't exist in the world of spreadsheets it seems. That's very saddening because I can't think of a much better tool for what I want to do. Copy paste it is until I need to use macros.
Depending on your specific use case, creating a user-defined function may help:
use the Basic IDE to create your function;
apply it to any cells on any sheet;
modifying the Basic code will affect all cells where the function is used.
I've elaborated the steps in an answer on superuser.
Sure, you could write some complex code to update functions, but wouldn't the easy way be just to drag it to the same range of cells the same way you did before? It should properly overwrite the existing code in there, and if it doesn't, you can just as easily delete the outdated code and drag the new code in.
Probably the best approach is to simply drag the amended formula over the range of cells (as advised by OldBunny2800). This is less error prone and easier to maintain than a custom macro.
Another option would be to use an array function. Then you only have to edit the function once, and the same edit will be automatically applied to the whole range of cells in that array function.

Xlrd list index out of range

I'm just starting to explore Xlrd, and to be honest am pretty new to programming altogether, and have been working through some of their simple examples, and can't get this simple code to work:
import xlrd
book=open_workbook('C:\\Users\\M\\Documents\\trial.xlsx')
sheet=book.sheet_by_index(1)
cell=sheet.cell(0,0)
print cell
I get an error: list index out of range (referring to the 2nd to last bit of code)
I cut and pasted most of the code from the pdf...any help?
You say:
I get an error: list index out of range (referring to the 2nd to last
bit of code)
I doubt it. How many sheets are there in the file? I suspect that there is only one sheet. Indexing in Python starts from 0, not 1. Please edit your question to show the full traceback and the full error message. I suspect that it will show that the IndexError occurs in the 3rd-last line:
sheet=book.sheet_by_index(1)
I would play around with it in the console.
Execute each statement one at a time and then view the result of each. The sheet indexes count from 0, so if you only have one worksheet then you're asking for the second one, and that will give you a list index out of range error.
Another thing that you might be missing is that not all cells exist if they don't have data in them. Some do, but some don't. Basically, the cells that exist from xlrd's standpoint are the ones in the matrix nrows x ncols.
Another thing is that if you actually want the values out of the cells, use the cell_value method. That will return you either a string or a float.
Side note, you could write your path like so: 'C:/Users/M/Documents/trial.xlsx'. Python will handle the / vs \ on the backend perfectly and you won't have to screw around with escape characters.

wxChoice::SetString() Index Error

I've finally gotten around to messing with the wxChoice control in my application, and for some reason whenever I attempt to modify the text of a column, I get the error:
....\src\msw\choice.cpp(348): assert "IsValid(n)" failed in
wxChoice::SetString(): invalid item index in wxChoice::SetString
The error itself makes it quite obvious that the item index isn't valid, but based off of my code and the (not very descriptive) documentation, I should only need to set the number of columns, then I'd be allowed to edit the text at a given index.
Here's a snippet from my project:
int phones = Phones->size();
choiceDevice->SetColumns(phones); // Value greater than 0
choiceDevice->SetString(phones - 1, pInstance->ProfileName); // Should assign the last index the value of the ProfileName.
What if Phones is empty, and thus phones == 0?
wxChoice::SetColumns
Remarks:
This is implemented for GTK and Motif only and doesn’t do anything under other platforms.
It looks like SetColumns is used for multi-column choice control, I have never seen it. Anyway, it doesn't add new items to the control. In Windows it does nothing in any case.
As Alex had said, I shouldn't be using wxChoice::SetColumns on Windows since it has no affect. I found that I have to use wxChoice::Append instead of setting the number of columns, then setting the individual string.

How to iterate over all the page breaks in an Excel 2003 worksheet via COM

I've been trying to retrieve the locations of all the page breaks on a given Excel 2003 worksheet over COM. Here's an example of the kind of thing I'm trying to do:
Excel::HPageBreaksPtr pHPageBreaks = pSheet->GetHPageBreaks();
long count = pHPageBreaks->Count;
for (long i=0; i < count; ++i)
{
Excel::HPageBreakPtr pHPageBreak = pHPageBreaks->GetItem(i+1);
Excel::RangePtr pLocation = pHPageBreak->GetLocation();
printf("Page break at row %d\n", pLocation->Row);
pLocation.Release();
pHPageBreak.Release();
}
pHPageBreaks.Release();
I expect this to print out the row numbers of each of the horizontal page breaks in pSheet. The problem I'm having is that although count correctly indicates the number of page breaks in the worksheet, I can only ever seem to retrieve the first one. On the second run through the loop, calling pHPageBreaks->GetItem(i) throws an exception, with error number 0x8002000b, "invalid index".
Attempting to use pHPageBreaks->Get_NewEnum() to get an enumerator to iterate over the collection also fails with the same error, immediately on the call to Get_NewEnum().
I've looked around for a solution, and the closest thing I've found so far is http://support.microsoft.com/kb/210663/en-us. I have tried activating various cells beyond the page breaks, including the cells just beyond the range to be printed, as well as the lower-right cell (IV65536), but it didn't help.
If somebody can tell me how to get Excel to return the locations of all of the page breaks in a sheet, that would be awesome!
Thank you.
#Joel: Yes, I have tried displaying the user interface, and then setting ScreenUpdating to true - it produced the same results. Also, I have since tried combinations of setting pSheet->PrintArea to the entire worksheet and/or calling pSheet->ResetAllPageBreaks() before my call to get the HPageBreaks collection, which didn't help either.
#Joel: I've used pSheet->UsedRange to determine the row to scroll past, and Excel does scroll past all the horizontal breaks, but I'm still having the same issue when I try to access the second one. Unfortunately, switching to Excel 2007 did not help either.
Experimenting with Excel 2007 from Visual Basic, I discovered that the page break isn't known unless it has been displayed on the screen at least once.
The best workaround I could find was to page down, from the top of the sheet to the last row containing data. Then you can enumerate all the page breaks.
Here's the VBA code... let me know if you have any problem converting this to COM:
Range("A1").Select
numRows = Range("A1").End(xlDown).Row
While ActiveWindow.ScrollRow < numRows
ActiveWindow.LargeScroll Down:=1
Wend
For Each x In ActiveSheet.HPageBreaks
Debug.Print x.Location.Row
Next
This code made one simplifying assumption:
I used the .End(xlDown) method to figure out how far the data goes... this assumes that you have continuous data from A1 down to the bottom of the sheet. If you don't, you need to use some other method to figure out how far to keep scrolling.
Did you set ScreenUpdating to True, as mentioned in the KB article?
You may want to actually toggle it to True to force a screen repaint. It sounds like the calculation of page breaks is a side-effect of actually rendering the page, rather than something Excel does on demand, so you have to trigger a page rendering on the screen.