How to Include QwtPolar in Project

[cr7tiano]

Hi,

I have succesfully run those examples in qwtpolar, however i can't build a simple project by including qwtpolar.

For Qwt, I include it by adding following lines to . pro file:
QWT_LOCATION = /usr/local/qwt-6.1.0/
INCLUDEPATH += $${QWT_LOCATION}/include/
LIBS = -L$${QWT_LOCATION}/lib -lqwt

However, I have no clue how to do that for qwtpolar.

Thanks in advance.

[ChrisW67]

You can either use exactly the same pattern with paths and library names that match qwtpolar:

QWTPOLAR_LOCATION = /usr/local/qwtpolar-1.1.0-svn-qt4
INCLUDEPATH += $${QWTPOLAR_LOCATION}/include/
LIBS = -L$${QWTPOLAR_LOCATION}/lib -lqwtpolar

QWTPOLAR_LOCATION = /usr/local/qwtpolar-1.1.0-svn-qt4
INCLUDEPATH += $${QWTPOLAR_LOCATION}/include/
LIBS = -L$${QWTPOLAR_LOCATION}/lib -lqwtpolar

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Alternatively you can include both qwt and qwtpolar in your project using the instructions at the bottom of each library's INSTALL text file.

// leave all the other stuff out and
CONFIG += qwt qwtpolar

// leave all the other stuff out and
CONFIG += qwt qwtpolar

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If you have built qwt/qwtpolar and run "make install" as in the instructions then the qwt.prf and qwtpolar.prf files may be in the default serach location. If not, then you might need to give qmake a few other places to look:

$ qmake -query QMAKEFEATURES
// nothing
$ qmake -set QMAKEFEATURES "/usr/local/qwt-6.1.0-svn-qt4/features:/usr/local/qwtpolar-1.1.0-svn-qt4/features"
$ qmake -query QMAKEFEATURES
/usr/local/qwt-6.1.0-svn-qt4/features:/usr/local/qwtpolar-1.1.0-svn-qt4/features
 
$ qmake yourproject.pro
// etc...

$ qmake -query QMAKEFEATURES
// nothing
$ qmake -set QMAKEFEATURES "/usr/local/qwt-6.1.0-svn-qt4/features:/usr/local/qwtpolar-1.1.0-svn-qt4/features"
$ qmake -query QMAKEFEATURES
/usr/local/qwt-6.1.0-svn-qt4/features:/usr/local/qwtpolar-1.1.0-svn-qt4/features

$ qmake yourproject.pro
// etc...

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[cr7tiano]

I am able to run the qmake and make the pro. file. However, if I build the project from the Qt creator , this error is shown:
*** glibc detected *** /home/user/Qt/build-mls_polar-Desktop_Qt_5_2_0_GCC_64bit-Release/mls_polar: realloc(): invalid pointer: 0x00007fbbcf803da0 ***

What's the problem?

[ChrisW67]

At a guess, your code is using an uninitialised or invalid pointer.