php的gdchart介绍
gdchart是PECL的一个类库。也就是说它是一个C语言的扩展。虽然，目前PHP没有默认安装gdchart，但如果想使用，还是可以编译的。
gdchart最大的好处不仅是效率高，速度快，同时，另外一点则是，使用极为方便。以下是一些实例说明。
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线形图：
<?phpHeader("Content-type: image/png");$chart = new gdchart(LINE);$chart->add(array(2.5, 5.1, 8.6, 12.0, 15, 9, 8, 7));$chart->add(array(5.0, 8.0, 9.2, 10.2, 7, 8, 10, 9));$chart->add(array(8.0, 10.0, 14.0, 18.2, 16, 14, 12, 10));$chart->labels = array("Jan","Feb","Mar","Apr","May","Jun","Jul", "Aug");$chart->colors = array(0x1133aa, 0xaa3311, 0x33aa11);$chart->out(640,480,IMG_PNG);?>?
自定义坐标线形图
<?phpHeader("Content-type: image/png");$chart = new gdchart(LINE);$chart->add(array(2.5, 5.1, 8.6, 12.0, 15, 9, 8, 7));$chart->add(array(5.0, 8.0, 9.2, 10.2, 7, 8, 10, 9));$chart->add(array(8.0, 10.0, 14.0, 18.2, 16, 14, 12, 10));$chart->labels = array("Jan","Feb","Mar","Apr","May","Jun","Jul", "Aug");$chart->requested_ymin = 0;$chart->ylabel_density = 25;$chart->ylabel_fmt = "%.0f";$chart->colors = array(0x001133aa, 0x00aa3311, 0x33aa11);$chart->out(640,480,IMG_PNG);?>?
3D区域图
<?phpHeader("Content-type: image/png");$chart = new gdchart(AREA_3D);$chart->depth = 5;$chart->xtitle = "Fruits";$chart->xtitle_color = 0xffff00;$chart->bg_color = 0x112233;$chart->xlabel_color = 0xffffff;$chart->ylabel_color = 0xffffff;$chart->colors = array(0x30ffff00, 0x30ff00ff, 0x3000ffff);$chart->add(array(2.5, 5.1, 8.6, 12.0));$chart->add(array(5.0, 8.0, 9.2, 10.2));$chart->add(array(8.0, 10.0, 14.0, 18.2));$chart->labels = array("Apples","Oranges","Melons","Pears");$chart->out(640,480,IMG_PNG);?>?
饼图
<?phpHeader("Content-type: image/png");$chart = new gdchart(PIE_3D);$chart->title = "This is a Sample Pie Chart";$chart->title_font = "/usr/share/fonts/truetype/CANDY.ttf ";$chart->title_ptsize = 24;$chart->label_font = "/usr/share/fonts/truetype/Jester.ttf";$chart->label_ptsize = 16;$chart->edge_color = 0x000000;$chart->labels = array("red","green\r\n(exploded)","lt blue","purple","missing","cyan","blue");$chart->add(array(12.5, 20.1, 2.0, 22.0, 5.0, 18.0, 13.0));$chart->missing = array(FALSE, FALSE, FALSE, FALSE, TRUE, FALSE, FALSE);$chart->explode = array(0,40,0,0,0,0,0);$chart->pie_depth = 30;$chart->perspective = 0;$chart->pie_angle = 90;$chart->label_line = false;$chart->percent_labels = LABEL_ABOVE;$chart->out(640,480,IMG_PNG);?>?3D高低位闭合图
<?phpHeader("Content-type: image/png");$chart = new gdchart(COMBO_HLC_AREA_3D);$chart->title = "High-Low-Close On top of an Area(volume) Graph";$chart->depth = 5.0;$chart->angle = 50;$chart->annotation_font_size = FONT_TINY;$chart->anno_note = "Earnings\nReport";$chart->anno_point = 8;$chart->vol_color = 0x40806040;$chart->grid = TICK_LABELS;$chart->ylabel_density = 40;$chart->hlc_style = HLC_CONNECTING | HLC_I_CAP | HLC_DIAMOND;$chart->add_scatter(17.0, 3, SCATTER_TRIANGLE_UP, 0x50808060, 30);$chart->add(array(17.8,17.1,17.3,17.2,17.1,17.3,17.3,17.3,17.1,17.5,17.4));$chart->add(array(16.4,16.0,15.7,15.25,16.0,16.1,16.8,16.5,16.8,16.2,16.0));$chart->add(array(17.0,16.8,16.9,15.9,16.8,17.2,16.8,17.0,16.9,16.4,16.1));$chart->add_combo(array(150.0,100.0,340.0,999.0,390.0,420.0,150.0,100.0,340.0,1590.0,700.0));$chart->labels =array("May","Jun","Jul","Aug","Sep","Oct","Nov","Dec","Jan","Feb","Mar","Apr");$chart->out(640,480,IMG_PNG);?>?
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