CHARTS WITH MATPLOTLIB
======================

This test is done with chart generated by **matplotlib**, a famous charts
library for Python Language. You can get it from

    http://matplotlib.sourceforge.net

Charts is other important thing in reports. Geraldo is compatible with every
library charts since it has a way to render the chart as a common image format,
like JPG, PNG, GIF, etc.

    >>> import os
    >>> cur_dir = os.path.dirname(os.path.abspath(__file__))

    >>> from django.contrib.auth.models import User

    >>> from reportlab.lib.pagesizes import A4
    >>> from reportlab.lib.units import cm
    >>> from reportlab.lib.enums import TA_CENTER, TA_JUSTIFY, TA_RIGHT
    >>> from reportlab.lib.colors import navy, yellow, red
    
    >>> from geraldo import Report, ReportBand, Label, ObjectValue, SystemField,\
    ...     FIELD_ACTION_COUNT, FIELD_ACTION_AVG, FIELD_ACTION_MIN,\
    ...     FIELD_ACTION_MAX, FIELD_ACTION_SUM, FIELD_ACTION_DISTINCT_COUNT, BAND_WIDTH,\
    ...     RoundRect, Line, Image

Report class

    >>> class UsersReport(Report):
    ...     title = 'Using chart from CairoPlot'
    ... 
    ...     class band_summary(ReportBand):
    ...         height = 5*cm
    ...         elements = [
    ...             Label(text="Users count:", top=0.1*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='username', top=0.1*cm, left=4*cm,\
    ...                 action=FIELD_ACTION_COUNT, display_format='%s permissions found'),
    ... 
    ...             Label(text="Users ids average:", top=0.6*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='id', top=0.6*cm, left=4*cm, action=FIELD_ACTION_AVG),
    ... 
    ...             Label(text="Users ids minimum:", top=1.1*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='id', top=1.1*cm, left=4*cm, action=FIELD_ACTION_MIN),
    ... 
    ...             Label(text="Users ids maximum:", top=1.6*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='id', top=1.6*cm, left=4*cm, action=FIELD_ACTION_MAX),
    ... 
    ...             Label(text="Users ids sum:", top=2.1*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='id', top=2.1*cm, left=4*cm, action=FIELD_ACTION_SUM),
    ... 
    ...             Label(text="Users first name distinct:", top=2.6*cm, left=0.2*cm),
    ...             ObjectValue(attribute_name='first_name', top=2.6*cm, left=4*cm, action=FIELD_ACTION_DISTINCT_COUNT),
    ... 
    ...             Image(filename=os.path.join(cur_dir, 'output/matplotlib.png'), left=11*cm, top=0.2*cm)
    ...         ]
    ...         borders = {'top': True}
    ... 
    ...     class band_page_header(ReportBand):
    ...         height = 1.3*cm
    ...         elements = [
    ...             SystemField(expression='%(report_title)s', top=0.1*cm, left=0, width=BAND_WIDTH,
    ...                 style={'fontName': 'Helvetica-Bold', 'fontSize': 14, 'alignment': TA_CENTER,
    ...                     'textColor': navy}),
    ...             Label(text="ID", top=0.8*cm, left=0),
    ...             Label(text="Username", top=0.8*cm, left=3*cm),
    ...             Label(text="First name", top=0.8*cm, left=8*cm),
    ...             Label(text="Last name", top=0.8*cm, left=13*cm),
    ...             Label(text="Staff", top=0.8*cm, left=18*cm),
    ...         ]
    ...         borders = {'bottom': Line(stroke_color=navy)}
    ... 
    ...     class band_page_footer(ReportBand):
    ...         height = 0.5*cm
    ...         elements = [
    ...             Label(text='Created with Geraldo Reports', top=0.1*cm,
    ...                 right=0),
    ...             SystemField(expression='Printed in %(now:%Y, %b %d)s at %(now:%H:%M)s', top=0.1*cm,
    ...                 width=BAND_WIDTH, style={'alignment': TA_RIGHT}),
    ...         ]
    ...         borders = {'top': True}
    ... 
    ...     class band_detail(ReportBand):
    ...         height = 0.7*cm
    ...         elements = [
    ...             ObjectValue(attribute_name='id', top=0, left=0),
    ...             ObjectValue(attribute_name='username', top=0, left=3*cm, display_format='<font size=14 name=Helvetica>%s</font>'),
    ...             ObjectValue(attribute_name='first_name', top=0, left=8*cm),
    ...             ObjectValue(attribute_name='last_name', top=0, left=13*cm),
    ...             ObjectValue(attribute_name='is_staff', top=0, left=18*cm,
    ...                 get_value=lambda instance: instance.is_staff and 'Yes' or 'No'),
    ...         ]

    >>> queryset = User.objects.order_by('id')

    >>> report = UsersReport(queryset=queryset)

Creating some users

    >>> len([User.objects.get_or_create(username='Leticia'),
    ... User.objects.get_or_create(username='Tarsila', is_staff=True),
    ... User.objects.get_or_create(username='Mychelle', is_staff=True),
    ... User.objects.get_or_create(username='Mychell', is_staff=True),
    ... User.objects.get_or_create(username='Betty', is_staff=True),
    ... User.objects.get_or_create(username='Marta'),
    ... User.objects.get_or_create(username='Davi'),
    ... User.objects.get_or_create(username='Verinha'),
    ... User.objects.get_or_create(username='Miltinho'),
    ... User.objects.get_or_create(username='Waltinho'),
    ... User.objects.get_or_create(username='Leni')])
    11

Getting data

    >>> from geraldo.generators import PDFGenerator
    >>> report.queryset = User.objects.order_by('id')

Building the chart

    >>> try:
    ...     import pylab
    ...     from numpy import numarray
    ... except ImportError:
    ...     numarray = pylab = None

    >>> if pylab and numarray:
    ...     user_ids = report.queryset.filter(id__in=[1,5,7,12]).values('id','username')
    ...     labels = [user['username'] for user in user_ids]
    ...     data = [user['id'] for user in user_ids]
    ...     left = numarray.array(range(len(data))) + 0.5
    ...     
    ...     tmp = pylab.bar(left, data, width=0.5)
    ...     tmp = pylab.yticks(range(15))
    ...     tmp = pylab.xticks(left+0.25, labels)
    ...     tmp = pylab.title('Users IDs')
    ...     pylab.gca().get_xaxis().tick_bottom()
    ...     pylab.gca().get_yaxis().tick_left()
    ...     pylab.savefig(os.path.join(cur_dir, 'output/matplotlib.png'), dpi=50)

PDF generation

    >>> if pylab and numarray:
    ...     report.generate_by(PDFGenerator, filename=os.path.join(cur_dir, 'output/charts-matplotlib-report.pdf'))

