added save to file object in agg

svn path=/trunk/matplotlib/; revision=544

Author: jdh2358

CHANGELOG

@@ -1,6 +1,8 @@
 New entries should be added at the top
 
 ==============================================================
+2004-09-28 Added save to file object for agg - see
+           examples/print_stdout.py
 
 2004-09-24 Reorganized all py code to lib subdir
 

examples/fill_between.py

@@ -0,0 +1,20 @@
+from matplotlib.matlab import *
+from matplotlib.patches import Polygon
+
+def fill_between(ax, x, y1, y2, **kwargs):
+    # add x,y2 in reverse order
+    verts = zip(x,y1) + [(x[i], y2[i]) for i in range(len(x)-1,-1,-1)]
+    poly = Polygon(verts, **kwargs)
+    ax.add_patch(poly)
+    ax.autoscale_view()
+    return poly
+
+x = arange(0, 2, 0.01)
+y1 = sin(2*pi*x)
+y2 = sin(4*pi*x) + 2
+ax = gca()
+
+p = fill_between(ax, x, y1, y2, facecolor='g')
+p.set_alpha(0.5)
+show()
+                 

examples/print_stdout.py

@@ -0,0 +1,11 @@
+# print png to standard out
+# usage: python print_stdout.py > somefile.png
+import sys
+import matplotlib
+matplotlib.use('Agg')
+from matplotlib.matlab import *
+
+plot([1,2,3])
+
+savefig(sys.stdout)
+show()

examples/simple_plot.py

@@ -5,13 +5,13 @@
 figure(1)
 t = arange(0.0, 1.0, 0.01)
 s = cos(2*2*pi*t)
-plot(t, s, antialiased=False)
+plot(t, s)
 
 xlabel('time (s)')
 ylabel('voltage (mV)')
 title('About as simple as it gets, folks')
 grid(True)
 #axis([0,1,-1,1])
-savefig('simple_plot')
+#savefig('simple_plot')
 
 show()

lib/matplotlib/backends/backend_agg.py

@@ -322,9 +322,13 @@ def print_figure(self, filename, dpi=150,
 
         If the extension matches BMP or RAW, write an RGBA bitmap file
 
+        If filename is a fileobject, write png to file object (thus
+        you can, for example, write the png to stdout
         """
         if DEBUG: print 'FigureCanvasAgg.print_figure'
 
+            
+
         # store the orig figure dpi, color and size information so we
         # can restore them later.  For image creation alone, this is
         # not important since after the print the figure is done.  But
@@ -344,34 +348,38 @@ def print_figure(self, filename, dpi=150,
         # render the printed figure
         self.draw()
 
-        # take a look at the extension and choose the print handler
-        basename, ext = os.path.splitext(filename)
-        if not len(ext):
-            ext = '.png'
-            filename += ext
-
-        ext = ext.lower()
-        if (ext.find('rgb')>=0 or
-            ext.find('raw')>=0 or
-            ext.find('bmp')>=0 ):
-            # agg doesn't handle unicode yet
-            self.renderer._renderer.write_rgba(str(filename))
-        elif ext.find('png')>=0:
-            # agg doesn't handle unicode yet
-            self.renderer._renderer.write_png(str(filename))
-            #pass
-        elif ext.find('svg')>=0:
-	    from backend_svg import FigureCanvasSVG
-	    svg = self.switch_backends(FigureCanvasSVG)
-            svg.figure.dpi.set(72)
-	    svg.print_figure(filename, 72, facecolor, edgecolor, orientation)
-        elif ext.find('ps')>=0 or ext.find('ep')>=0:
-            from backend_ps import FigureCanvasPS # lazy import
-            ps = self.switch_backends(FigureCanvasPS)
-            ps.figure.dpi.set(72)
-            ps.print_figure(filename, 72, facecolor, edgecolor, orientation)
+        if  isinstance(filename, file):
+            # assume png and write to fileobject
+            self.renderer._renderer.write_png(filename)
         else:
-            error_msg('Do not know know to handle extension *%s' % ext)
+            # take a look at the extension and choose the print handler
+            basename, ext = os.path.splitext(filename)
+            if not len(ext):
+                ext = '.png'
+                filename += ext
+
+            ext = ext.lower()
+            if (ext.find('rgb')>=0 or
+                ext.find('raw')>=0 or
+                ext.find('bmp')>=0 ):
+                # agg doesn't handle unicode yet
+                self.renderer._renderer.write_rgba(str(filename))
+            elif ext.find('png')>=0:
+                # agg doesn't handle unicode yet
+                self.renderer._renderer.write_png(str(filename))
+                #pass
+            elif ext.find('svg')>=0:
+                from backend_svg import FigureCanvasSVG
+                svg = self.switch_backends(FigureCanvasSVG)
+                svg.figure.dpi.set(72)
+                svg.print_figure(filename, 72, facecolor, edgecolor, orientation)
+            elif ext.find('ps')>=0 or ext.find('ep')>=0:
+                from backend_ps import FigureCanvasPS # lazy import
+                ps = self.switch_backends(FigureCanvasPS)
+                ps.figure.dpi.set(72)
+                ps.print_figure(filename, 72, facecolor, edgecolor, orientation)
+            else:
+                error_msg('Do not know know to handle extension *%s' % ext)
 
         # restore the original figure properties
         self.figure.dpi.set(origDPI)

lib/matplotlib/numerix.py

@@ -66,3 +66,6 @@
         from na_imports import *
 else:
     raise RuntimeError("invalid numerix selector")
+
+# a bug fix for blas numeric suggested by Fernando Perez
+matrixmultiply=dot

src/_backend_agg.cpp

@@ -943,9 +943,19 @@ RendererAgg::write_png(const Py::Tuple& args)
 
   args.verify_length(1);
 
-  std::string fileName = Py::String(args[0]);
-  const char *file_name = fileName.c_str();
   FILE *fp;
+  Py::Object o = Py::Object(args[0]);
+
+  if (o.isString()) {
+    std::string fileName = Py::String(o);
+    const char *file_name = fileName.c_str();
+    fp = fopen(file_name, "wb");
+  }
+  else {
+    if ((fp = PyFile_AsFile(o.ptr())) == NULL) 
+      throw Py::TypeError("Could not convert object to file pointer");
+  }
+
   png_structp png_ptr;
   png_infop info_ptr;
   struct        png_color_8_struct sig_bit;
@@ -956,7 +966,7 @@ RendererAgg::write_png(const Py::Tuple& args)
     row_pointers[row] = pixBuffer + row * width * 4;
   }
 
-  fp = fopen(file_name, "wb");
+
   if (fp == NULL) 
     throw Py::RuntimeError("could not open file");