My C++ application generates a .csv file containing 10000 floats.
Now the requirement is that there should be a graph in the same file depicting those floats.
I understand that csv files cannot have graphs. So I have to switch to Excel
Assuming I can write data into columns in excel sheet can anybody tell me if there is any function that I can call in my C++ program which will plot the data in excel sheet?
I have seen some solutions based on Python, but I am exploring if it is possible from C++ only.
www.google.com/search?q=C%2B%2B+Excel+OLE
The MSDN documentation is also often useful.
Try this library SimpleXlsxWriter. It is possible to plot basic graphs on the separate sheet in the excel book. There are also some examples of using on the wiki page of the project
The library provides no external dependencies
This might be of use, especially the last chapter:
www.maths.manchester.ac.uk/~ahazel/EXCEL_C++.pdf
CSV is a graph format.
It stands for Comma Separated Value.
You can load this file into Excel.
It will also import into SQL, MYSQL use (PHPMyadmin for this).
SQL stands for Structured Query Language. MYSQL is web based.
Best wishes to you.
http://www.whatisacnc.com
I have seen programs exporting to Excel in two different ways.
Opening Excel and entering data cell by cell (while it is running it looks like a macro at work)
Creating an Excel file on disk and writing the data to the file (like the Export feature in MS Access)
Number 1 is terribly slow and to me it is just plain aweful.
Number 2 is what I need to do. I'm guessing I need some sort of SDK so that I can create Excel files in C++.
Do I need different SDKs for .xls and .xlsx?
Where do I obtain these? (I've tried Googling it but the SDKs I've found looks like they do other things than providing an interface to create Excel files).
When it comes to the runtime, is MS Office a requirement on the PC that needs to create Excel files or do you get a redistributable DLL that you can deploy with your executable?
You can easily do that by means of the XML Excel format. Check the wikipedia about that:
http://en.wikipedia.org/wiki/Microsoft_Excel#XML_Spreadsheet
This format was introduced in Excel 2002, and it is an easy way to generate a XLS file.
You can also try working with XLS/XLSX files over ODBC or ADO drivers just like databases with a limited usage. You can use some templates if you need formatting or create the files from stratch. Of course you are limited by playing with the field values that way. For styling etc. you will need to use an Excel API like Microsoft's.
I'm doing this via Wt library's WTemplate
In short, I created the excel document I wanted in open office, and save-as excel 2003 (.xml) format.
I then loaded that in google-chrome to make it look pretty and copied it to the clipboard.
Now I'm painstakingly breaking it out into templates so that Wt can render a new file each time.
How can i make user to downlaoad a excel from the django app.i HAVE A MODEL WHICH gives the report.Now i want a option from user can download the file in excel form.ANy Solution
You can output the data as .csv which is easily imported into MS Excel.
http://docs.djangoproject.com/en/dev/howto/outputting-csv/
EDIT
After I wrote that I got curious if there actually was some way to do it directly to excel format and found:
http://www.python-excel.org/
That made me wonder why you didn't google your question before posted it here.....
I'm not sure quite what you're asking. If you're asking how can you generate output that's able to be read into Excel, IMO your best bet is using a CSV (see amoeba's response) as that's pretty generic. There are ways of using true Excel formats as well.
I'm thinking though that perhaps you're asking how you can have a user click a link (or whatever) and have Excel pop up with your data in it? (IOW, you've already generated the output).
I suppose I'd say a few things:
1) It shouldn't be specific to Excel, many users use things like OO.o (thus my CSV suggestion)
2) It's going to vary depending on their browser and how they have it set up. Personally, I don't like pages opening up the "proper application" so I turn all of that off - other people enable it.
I'm using wxWidgets to write cross-plafrom applications. In one of applications I need to be able to load data from Microsoft Excel (.xls) files, but I need this to work on Linux as well, so I assume I cannot use OLE or whatever technology is available on Windows.
I see that there are many open source programs that can read excel files (OpenOffice, KOffice, etc.), so I wonder if there is some library that I could use?
Excel files it needs to support are very simple, straight tabular data. I don't need to extract any formatting except column/row position and the data itself.
Suggestedd reference: What is a simple and reliable C library for working with Excel files?
I came across other libraries (chicago on sf.net, xlsLib) but they seem to be outdated.
jrh
I can say that I know of a wxWidgets application that reads Excel .xls and .xlsx files on any platform. For the .xlsx files we used an XML parser and zip stream reader and grab the data we need, pretty easy to get going. For the .xls files we used: ExcelFormat, which works well and we found the author to be very generous with his support.
Maybe just some encouragement to give it a go? It was a couple of days work to get working.
Maybe http://www.libxl.com/ can help ?
I think that it is not something easy to do. xls files are quite complex and it is a proprietary format.
Maybe this is a stupid idea but why don't you upload and access your doc with Google docs. There are some apis to access your doc.
2 potential problems:
- Your app needs internet access
- Currently there is no C++ api.
But there are api for several languages including python see http://code.google.com/intl/fr/apis/gdata/articles/python_client_lib.html
How to read/write data into excel 2007 in c++?
Excel provides COM interface which you can use from your C++ application.
I have experience with Excel 2003 only but I think for excel 2007 it will also work.
This can be done e.g. with #import or in the way described in this article:
http://support.microsoft.com/kb/216686
There is a python solution (using COM dispatch) here: http://snippets.dzone.com/posts/show/2036
It's not C++, but the COM interface should be the same no matter which language you use, right?
You wouldn't need to port everything. Just __init__, set_range, get_value, set_value, save (or save_as), close, and quit. You might also need to dispose of garbage (as python has automatic gc).
Or you could just port (and modify) the following code (which I haven't tested, as I don't have excel anymore - you should probably check it by downloading python and pythonwin):
from win32com.client import Dispatch
app = Dispatch("Excel.Application")
app.Visible = True # spooky - watch the app run on your desktop!
app.Workbooks.Open("C:\\book.xls")
range = app.ActiveWorkbook.Sheets(1).Range("a1")
print 'The range was:'
print range.Value
range.Value = 42
print 'The value is now 42'
app.ActiveWorkbook.Save()
app.ActiveWorkbook.SaveAs("C:\\excel2.xls")
app.ActiveWorkbook.Close()
app.Quit()
# any gc to do?
Excel 2007 files are simply zip files. Try to rename .xlsx to .zip: you can extract files and folders. With a text editor you can view that they are all XML files.
So the solution:
use a common class to unzip your xlsx
use an xml parser to grab you data
if you have modified somethig, re-zip all
No COM object required.
Depending on your c++ compiler you can easyly find the required sources.
There are three main things you need to do.
1) Ensure pre-requisite files are installed and locatable.
Blindingly obvious I know, but make sure you have a suitable version of Excel installed, so that you can locate the required Microsoft libraries (and their locations).
namely MSO.DLL, VBE6EXT.OLB and EXCEL.EXE
2) Set up the Microsoft libraries.
In your C++ code, let's say you start with a simple console application, be sure to include the import libraries in any C++ application that interfaces with Excel. In my example I use:
#import "C:\\Program Files (x86)\\Common Files\\microsoft shared\\OFFICE11\\MSO.DLL" \
rename( "RGB", "MSORGB" )
using namespace Office;
#import "C:\\Program Files (x86)\\Common Files\\microsoft shared\\VBA\\VBA6\\VBE6EXT.OLB"
using namespace VBIDE;
#import "C:\\Program Files (x86)\\Microsoft Office\\OFFICE11\\EXCEL.EXE" \
rename( "DialogBox", "ExcelDialogBox" ) \
rename( "RGB", "ExcelRGB" ) \
rename( "CopyFile", "ExcelCopyFile" ) \
rename( "ReplaceText", "ExcelReplaceText" ) \
exclude( "IFont", "IPicture" ) no_dual_interfaces
3) Use the Excel Object Model in your C++ code
For example, to declare an Excel Application Object pointer for reading / writing an Excel Workbook:
Excel::_ApplicationPtr pXL;
pXL->Workbooks->Open( L"C:\\dump\\book.xls" );
And to access and manipulate the Excel Worksheet and the cells within it:
Excel::_WorksheetPtr pWksheet = pXL->ActiveSheet;
Excel::RangePtr pRange = pWksheet->Cells;
double value = pRange->Item[1][1];
pRange->Item[1][1] = 5.4321;
And so on. I have a more in-depth discussion at this following blog posting.
A low tech way I have used on a couple of projects is to make a simple script/macro/whatever that runs an external program. Write that external program in C++. Get that external program to read its input from and write its output to a .csv file (simple comma separated value text file). Excel can easily read and write .csv files, so this setup gives you everything you need to craft a viable solution.
This can all be done via the IDispatch interface. It can get really bloody complicated quickly (Cheers Microsoft) but at least once you've got your head round Excel you'll find integrating with any other MS application easy too :)
Fortunately there is someone over on codeguru who has made the process nice and easy. Once I'd read through that code I started to get my head round what excel was doing and, furthermore, i found it became REALLY easy to extend it to do other things that I wanted. Just remember that you are sending commands to Excel via the IDispatch interface. This means you need to think about how YOU would do something to figure out how to do it programatically.
Edit: the code guru example is for Excel 2003 but it should be fairly easy to extend it to 2007 :)
Start here with the OpenXml Sdk. Download the SDK from here. The SDK uses .NET, so you might need to use C++.NET
It has been a very long time but I have used the Jet OLEDB to get at Excel files. You might start searching in that direction.
I have used a 3rd Party component for this in the past: OLE XlsFile from SM Software (not free, but inexpensive). The advantage of this component over the Microsoft COM components is that you can use it to write XLS files even if Excel is not installed.
It also allows you to create speadsheets or workbooks with embedded formulas and formatting, something not possible if you use CSV files as an interchange format.
If you need the best performance, writing binary Excel files is the way to go and writing them is not as difficult as reading them. The binary file format is relatively well documented by the OpenOffice.org project:
http://sc.openoffice.org/excelfileformat.pdf
and Microsoft has also released the documentation:
http://download.microsoft.com/download/0/B/E/0BE8BDD7-E5E8-422A-ABFD-4342ED7AD886/Excel97-2007BinaryFileFormat(xls)Specification.xps
This solution will work best if you have to write many Excel files, mostly with data and little formatting, and if you don't want to open the files at the same time. If you write a single Excel file to open it afterwards, you can probably use the propsed C++ COM Interface as the other posters have explained.
Using the COM interface will necessitate expensive out-of-process calls unless you write an Excel COM Addin. If you write an Addin that imports your data into the current Excel sheet, filling the sheet will still be much slower than dumping a file, but for a single file at a time this can be acceptable depending on your user scenario. If you do decide to use the COM interface, minimize the number of calls to Excel. Use the methods that allow to insert an array of values if they exist, set style properties by row and column is possible and not per cell.
You can use ODBC to read and write data from an excel file easily without Excel. The link:Here
The link for how to write data using odbc: Here
I've used a set of C++ classes that is available from CodeProject before to write to XLS files.
It's really easy to use, and free! You can find it here.
Took me no time to set up.