Is there a way to group if statements in Java

I am writing a function to produce an array however I have to apply lots of if statements that will affect the output.

I have tried just listing them but I think it is affecting my output somehow, it also looks very cumbersome.

  static double [] solve (equation b, int k)
{
double [] a = null;
if (b.c > 1)
{   
a = new double[k];
for (int i = 0; i < k; i++)
{
    b.x0 = (b.c*b.x0)/(b.y0) + (b.d*b.x0);
    b.y0 = b.e*(b.x0 + 1)*b.y0;
    a[i] = b.y0;
}
} 
if (b.d > 0)
{   
a = new double[k];
for (int i = 0; i < k; i++)
{
   b.x0 = (b.c*b.x0)/(b.y0) + (b.d*b.x0);
    b.y0 = b.e*(b.x0 + 1)*b.y0;
    a[i] = b.y0;
}
}
if (1 > b.e || b.e > 0)
{   
a = new double[k];
for (int i = 0; i < k; i++)
{
    b.x0 = (b.c*b.x0)/(b.y0) + (b.d*b.x0);
    b.y0 = b.e*(b.x0 + 1)*b.y0;
    a[i] = b.y0;
 }
return a;

Is there a way to group my if statements so that if my parameters are within the required range I will get a result and if they are not I will get 'null'. (there are also a few more if statements but this gets the idea across).