先看下最终效果:
下面为PHP代码:
- /******************************
- * 折线图生成函数
- ******************************/
- function line_stats_pic($value_y,$width,$high,$strong=1,$fix=0){
- //y值处理函数
- function line_point_y($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;
- }
-
- //参数处理
- $allnum=sizeof($value_y);
- $maxmax_num=max($value_y); //最大值
- $minmin_num=min($value_y); //最小值
- $limit_m=$max_num-$min_num; //极差
- $max_num_add=$max_num+$limit_m*0.1; //轴最大值
- $min_num_add=$min_num-$limit_m*0.1; //轴最小值
- $limit=$max_num_add-$min_num_add; //极差-坐标轴y
- $y_pxdensity=($max_num_add-$min_num_add)/$high; //y轴密度
- $x_pxdensity=floor($width/$allnum); //x轴密度
- reset($value_y); //将数组指针归零
- $i=0;
- foreach($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); //零点的y值
- $empty_size_x=(strlen($max_num) > strlen($min_num) ? strlen($max_num) : strlen($min_num))*5+3; //左边空白
-
- //图片流开始
- header("Content-type:image/png");
- $pic=imagecreate($width+$empty_size_x+10,$high+13);
- imagecolorallocate($pic,255,255,255);  
|