PHP Line chart generation functions and examples

/* * PHP generates a line chart * by bbs.it-home.org */ function Line_stats_pic ($value _y, $width, $high, $strong =1, $fix =0) { Y-Value processing function function line_point_y ($num, $width, $high, $max _num_add, $min _num_add, $y _pxdensity) { $return = $high-floor (($num-$min _num_add+ $y _pxdensity)/(($max _num_add-$min _num_add)/$high)); return $return; } Parameter handling $allnum =sizeof ($value _y); $max _num=max ($value _y); Maximum Value $min _num=min ($value _y); Minimum value $limit _m= $max _num-$min _num; Very poor $max _num_add= $max _num+ $limit _m*0.1; Axis Maximum Value $min _num_add= $min _num-$limit _m*0.1; Minimum axis value $limit = $max _num_add-$min _num_add; Extreme difference-Axis y $y _pxdensity= ($max _num_add-$min _num_add)/$high; Y-Axis density $x _pxdensity=floor ($width/$allnum); X-Axis Density Reset ($value _y); Zeroing array Pointer to zero $i = 0; foreach ($value _y as $val) { $point _y[$i]=line_point_y ($val, $width, $high, $max _num_add, $min _num_add, $y _pxdensity); $i + +; } $zero _y=line_point_y (0, $width, $high, $max _num_add, $min _num_add, $y _pxdensity); Y value of 0 points $empty _size_x= (strlen ($max _num) > strlen ($min _num)? strlen ($max _num): strlen ($min _num)) *5+3; Left blank Picture Stream Start Header ("Content-type:image/png"); $pic =imagecreate ($width + $empty _size_x+10, $high +13); Imagecolorallocate ($pic, 255,255,255); Background color $color _1=imagecolorallocate ($pic, 30,144,255); Line Color $color _2=imagecolorallocate ($pic, 0,0,0); Black $color _3=imagecolorallocate ($pic, 194,194,194);//Grey Draw Grid Imagesetthickness ($pic, 1); Grid line width $y _line_width=floor ($width/100); Number of vertical grid lines $y _line_density= $y _line_width==0? 0:floor ($width/$y _line_width); Vertical Grid line Density $point _zero_y= $zero _y > $high? $high: $zero _y; Imagestring ($pic, 1, $empty _size_x-1, $high +4, "0", $color _2); 0-Point Axis mark for ($i =1; $i <= $y _line_width; $i + +) {//Draw vertical grid lines Imagesetthickness ($pic, 1); Grid line width Imageline ($pic, $y _line_density* $i + $empty _size_x,0, $y _line_density* $i + $empty _size_x, $high, $color _3); Imagesetthickness ($pic, 2); Axis Point line width Imageline ($pic, $y _line_density* $i + $empty _size_x, $point _zero_y-4, $y _line_density* $i + $empty _size_x, $point _zero_y , $color _2); Imagestring ($pic, 1,100* $i + $empty _size_x-5, $high +4, $allnum/$y _line_width* $i, $color _2); Axis Mark } $x _line_width=floor ($high/30); Number of horizontal grid lines $x _line_density= $x _line_width==0? 0:floor ($high/$y _line_width); Horizontal Grid line Density if ($zero _y > $high) {//Draw horizontal grid lines Imagestring ($pic, 1,0, $high -3,round ($min _num_add, $fix), $color _2); 0-Point Axis mark for ($i =1; $i <= $x _line_width; $i + +) { Imagesetthickness ($pic, 1); Grid line width Imageline ($pic, 0+ $empty _size_x, $high-$x _line_density* $i, $width + $empty _size_x, $high-$x _line_density* $i, $color _3 ); Imagesetthickness ($pic, 2); Axis Point line width Imageline ($pic, 0+ $empty _size_x, $high-$x _line_density* $i, $empty _size_x, $high-$x _line_density* $i, $color _2); Imagestring ($pic, 1,0, $high-$x _line_density* $i -3,round ($limit/$x _line_width* $i + $min _num_add, $fix), $color _2); Axis Mark } }else{ Imagestring ($pic, 1, $empty _size_x-8, $zero _y, "0", $color _2); 0-Point Axis mark for ($i =1; $i <= ceil ($x _line_width/2); $i + +) { Imagesetthickness ($pic, 1); Grid line width Imageline ($pic, 0+ $empty _size_x, $zero _y-$x _line_density* $i, $width + $empty _size_x, $zero _y-$x _line_density* $i, $ Color_3); if ($zero _y+ $x _line_density* $i < $high) { Imageline ($pic, 0+ $empty _size_x, $zero _y+ $x _line_density* $i, $width + $empty _size_x, $zero _y+ $x _line_density* $i, $ Color_3); } Imagesetthickness ($pic, 2); Axis Point line width Imageline ($pic, 0+ $empty _size_x, $zero _y-$x _line_density* $i, $empty _size_x, $zero _y-$x _line_density* $i, $color _2) ; if ($zero _y+ $x _line_density* $i < $high) { Imageline ($pic, 0+ $empty _size_x, $zero _y+ $x _line_density* $i, $empty _size_x, $zero _y+ $x _line_density* $i, $color _2) ; } Imagestring ($pic, 1,0, $zero _y-$x _line_density* $i -3,round ($limit/$x _line_width* $i, $fix), $color _2); Axis Mark if ($zero _y+ $x _line_density* $i < $high) { Imagestring ($pic, 1,0, $zero _y+ $x _line_density* $i -3,round (-$limit/$x _line_width* $i, $fix), $color _2); Axis Mark } } } Drawing axes Imagesetthickness ($pic, 2); Axis width Imageline ($pic, 1+ $empty _size_x,0,1+ $empty _size_x, $high, $color _2); if ($zero _y > $high) {//x axis position Imageline ($pic, 0+ $empty _size_x, $high, $width + $empty _size_x, $high, $color _2); }else{ Imageline ($pic, 0+ $empty _size_x, $zero _y, $width + $empty _size_x, $zero _y, $color _2); } Create a polyline $point _x=0; $j = 0; Imagesetthickness ($pic, $strong); Line thickness while ($j +1 < $allnum) { Imageline ($pic, $point _x+2+ $empty _size_x, $point _y[$j], $point _x+ $x _pxdensity+2+ $empty _size_x, $point _y[$j +1],$ color_1); $point _x+= $x _pxdensity; $j + +; } Imagepng ($pic); Imagedestroy ($pic); } for ($i =0; $i <100; $i + +) { $value = rand (1,200); $value _y[]= $value; } Line_stats_pic ($value _y,500,100,1,1); ?> Copy Code

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