PyQwt Frequently Asked Questions

2. Can I use PyQwt and PyQwt3D with the Black Adder integrated development environment?
3. How do I integrate PyQwt with the Qt Designer and Eric?
4. Should I choose Numeric, numarray or NumPy?

Can I use PyQwt and PyQwt3D with the Black Adder integrated development environment?

No. The price of a professional or personal Black Adder license is much lower than the total price of a commercial license for Qt and PyQt, but Black Adder does not provide the tools to build extensions modules like PyQwt and PyQwt3D.

How do I integrate PyQwt with the Qt Designer and Eric?

You have to install the Qwt library and the Qwt designer plugin. If you have built PyQwt against a shared Qwt library, the designer plugin is probably already installed. If you have built PyQwt against the slightly patched version of Qwt included in PyQwt, you can either install the included Qwt library (safest) or the official Qwt library matching PyQwt (PyQwt-4.2.x matches with Qwt-4.2.0 and PyQwt-5.0.x with Qwt-5.0.y).

Make sure that the Qwt designer plugin is linked against the correct Qwt library. Try the ldd command (should work on most POSIX systems, but probably not on MacOS/X):

[packer@slow htdoc]$ ldd $QTDIR/plugins/designer/libqwtplugin.so \
| head -n 5

        linux-gate.so.1 =>  (0xffffe000)
        libqwt.so.4 => /usr/lib/qt3/lib/libqwt.so.4 (0x40023000)
        libqt-mt.so.3 => /usr/lib/qt3/lib/libqt-mt.so.3 (0x400be000)
        libpthread.so.0 => /lib/tls/libpthread.so.0 (0x407d6000)
        libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x407e6000)
[packer@slow htdoc]$

Should I choose Numeric, numarray, or NumPy?

NumPy is recommended for new code, because Numeric and numarray are unmaintained. Recent versions of PyQwt and PyQwt3D support NumPy (as well as Numeric and numarray).

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