编一函数,计算有50个元素的一维实数组中最大值的位置,main定义为y[50],y[i]=600*sin(y*0.16)

错误如下
Error E:\TURBOC2\C.C 28: Expression syntax in function main
Warning E:\TURBOC2\C.C 29: Possible use of 'max_1' before definition in funct
Warning E:\TURBOC2\C.C 30: Possible use of 'max_1' before definition in funct

程序如下

double vmax(double *d,int n)
{
int i,t=0;
double max_2=d[0],max_3;
if (n<0)
{return 0;
}

for(i=1;i<n;i++)
{max_3=max_2;
if (max_3<d[i])
{t=i;
max_2=d[i];
}
}
return(t);
}

main()
{
double y[50],max_1;
int j;
for(j=0;j<50;j++)
{
y[j]=600*sin(j*0.16);
}

max_1=double vmax(double y,int j);
printf("Max Number is %f",y[max_1]);
printf("Number is %f",max_1);
}

我基础太差劲，不知如何正确调用