我有以下输入:
double zmin;
double zmax;
int count;
int N; //Total number of element in result array
我想生成一个双数组序列,其中zmin为第一个值,zmax为最后一个值。但是从第二个值到最后一个,但它应该被(zmax-zmin)/ count所左右。
例:
zmin = 1;
zmax = 10;
count = 3
预期结果:
double[] result = { 1, 4, 7, 10}
我的尝试:
double[] result = Enumerable.Repeat(zmin, N).Select(iv => (iv +(zmax-zmin)/count)).ToArray();
public static IEnumerable<double> Range(double min, double max, double step)
{
double i;
for (i=min; i<=max; i+=step)
yield return i;
if (i != max+step) // added only because you want max to be returned as last item
yield return max;
}
这个不仅适用于数字,也适用于日期/时间更复杂的类型。
第二种方法允许提供结果选择器 - 在某些情况下很有用。
public static IEnumerable<TItem> Range<TItem>(
TItem itemFrom, TItem itemTo, Func<TItem, TItem> itemSelector
) where TItem : IComparable
{
// Call to the below method
return Range(itemFrom, itemTo, itemSelector, o => o);
}
public static IEnumerable<TItem> Range<TItem, TResult>(
TItem itemFrom, TItem itemTo, Func<TItem, TItem> itemSelector, Func<TItem, TResult> resultSelector
) where TItem : IComparable
{
while (true)
{
yield return resultSelector(itemFrom);
if ((itemFrom = itemSelector(itemFrom)).CompareTo(itemTo) > 0)
break;
}
}
用法:
Range(1, 10, o => o + 3);
1 4 7 10
Range(
DateTime.Now,
DateTime.Now.AddYears(1),
o => o.AddMonths(1),
o => o.ToString("MMMM"));
January February March April May June July August September October November December January