本程序可以绘制p3曲线，直接输入cv、cs、EX,也通过降雨或径流数据计算绘制

[cs,cv,ma] = p3plot(a,kk,b,bb,y1,cs_cv,ma,cs,cv,x0)

a=20 横向网格条数

kk=200 纵坐标标注间隔（间隔要是最大值和最小值差的整数倍）

b=2000 纵坐标最大值

bb=0 纵坐标最小值

y1=[] 降雨量，横向矩阵输入,如果没有请输入[]

cs_cv=[2] 没有，请输入[]

ma=[] 年平均降雨量，没有输入[]

cs=[] 没有，请输入[]

cv=[] 没有，请输入[]

x0=0.01 初始概率点，百分数,没有输入[]-　this program can draw P3 curve, direct input CV, CS, EX, also by rainfall or runoff data calculation and drawing

The　[cs, CV, ma] = p3plot (a, KK, B, BB, Y1, cs_cv, Ma, CS, CV, x0)

The　a=20　of the number of horizontal grid

The　kk=200　 longitudinal coordinate labeling interval (interval if the maximum value and the minimum value of the integer times the difference)

The　b=2000　of the maximum longitudinal coordinates

The　bb=0　of the minimum longitudinal coordinates

The　y1=[]　　rainfall, transverse matrix input, if not please input []

The　cs_cv=[2]　no, please enter []

The　ma=[]　of the average annual rainfall　no input [].

The　cs=[]　no, please enter []

The　cv=[]　no, please enter []

　 x0=0.01　initial probability, percentage, no input []